TL: The Product Is the Poison The Case for a Chlorine Phase-out SO: A GREENPEACE Report By Joe Thornton (GP) DT: July, 1991 Keywords: toxics chlorine production organochlorines greenpeace reports gp us great lakes canada / The author gratefully acknowledges Pat Costner, Jack Weinberg, Paul Johnston, Robert Ginsburg, and Jeff Howard, whose research and counsel were indispensable to the preparation of this report. Copyright (C) 1991 by Greenpeace U.S.A. 1436 U Street, N.W. Washington, DC 20009 Greenpeace Great Lakes Project 1017 W. Jackson Boulevard Chicago, IL 60607 (312) 666-3305 185 Spadina Avenue, #600 Toronto, Ontario MST 2C6 (416) 345-8408 Greenpeace is an international environmental organization dedicated to preserving the earth and all the life it supports. This publication is made possible by more than four million supporters around the world. CONTENTS Summary and Recommendations 1 Chlorine and Organochlorines in the Global Ecosystem Chlorine and Organochlorines in Nature Chlorine and Organochlorines in Industry Behavior of Organochlorines in the Environment Persistence in air Persistence in water Resistance to biodegradation Bioaccumulation Toxicity Global Accumulation of Organochlorines Government Responses to Organochlorine Pollution Shifting the Focus: From Individual Organochlorines to Chlorine 2 Organochlorines in the Great Lakes Ecosystem Assessing Chemical Mixtures Occurrence of Organochlorines in the Great Lakes Effects on Fish and Wildlife Lake trout Bald eagles Gulls, terns and cormorants Ecosystem and interspecies effects Effects on Humans Time Trends in Great Lakes Contamination 3 Chlorine and Organochlorines in Industry: Releases and By- Products Releases of Organochlorine Products By-Product Formation Chlorine Manufacture Chlorine Use Pulp and paper Water treatment Metallurgical process Combustion of Organochlorines Manufacture of Organochlorines Use of Organochlorines 4 Economics of the Chlorine Phase-Out Implications for Industries That Use Chlorine Reaction of Chlor-Alkali Corporations Protecting Workers References SUMMARY AND RECOMMENDATIONS The purpose of this report is to show that the industrial production of chlorine poses a severe threat to the ecosystem and must be phased out. CHLORINE, ORGANOCHLORINES, AND THE CHLOR ALKALI INDUSTRY The chlor-alkali industry starts with ordinary salt - an abundant, natural compound. The chemical name for ordinary salt is sodium chloride. Each molecule contains one atom of sodium bound to one atom of chlorine. Through a process called electrolysis, the chlor-alkali industry uses large amounts of electricity to break the bond between the sodium and chlorine atoms, splitting the salt molecule. The sodium reacts with water to form sodium hydroxide, sold commercially as caustic soda. Chlorine is released in the form of chlorine gas, also called "elemental chlorine." Chlorine gas is a human invention. It does not exist in nature, and there is no known natural process that creates it. Chlorine gas is extremely unstable and reactive: when it comes into contact with organic (carbon-containing) molecules, the chlorine binds tightly to the carbon atoms, creating new substances called organochlorines. These organochlorines may be produced on purpose or by accident. For instance, the chemical industry combines chlorine with petrochemicals to create thousands of organochlorine pesticides, plastics, solvents, refrigerants, and other chemicals. 11,000 organochlorines are now in commerce. The combination of chlorine with organic molecules takes place very quickly, and it produces a wide variety of organochlorines. When chlorine is used as bleach in pulp mills or as a disinfectant in sewage or water treatment, hundreds of organochlorine byproducts are formed. Similarly, when chlorine is used to manufacture specific organochlorine products, many unwanted by-products form, as well. These are collected as wastes or remain in the product as impurities. Whenever organochlorines are burned thousands more by-products are created. When organochlorines are used, by-products are frequently formed, especially in high-temperature or chemically unstable environments. These by-products include some of the most toxic and persistent organochlorines, such as the dioxins, furans, PCBs, and hexachlorobenzene. Even the least toxic organochlorine products produce the most dangerous organochlorines at some point in their industrial life-cycle. When organochlorines enter the environment, still more organochlorines are produced in reactions with sunlight, other chemicals, or biological agents already present in the ecosystem. PROPERTIES OF ORGANOCHLORINES Organochlorines are almost completely foreign to nature. In contrast to the thousands of organochlorines produced by the industrial use of chlorine, only one organochlorine compound - chloromethane - is produced in nature in significant quantities. The simplest of the organochlorines, chloromethane evidently plays a role in the natural regulation of the ozone layer. Many organochlorines are very stable. Once they enter the environment, they resist natural breakdown processes and persist for long periods of time. Some organochlorines can be broken down slowly in the environment, but the breakdown products--usually other organochlorines--are often more toxic and persistent than the original substance. Breakdown is not complete until the chlorine atom has once again been incorporated into salt (or some other inorganic molecule, such as hydrochloric acid). Complete breakdown of organochlorines takes place extremely slowly, requiring hundreds of years or more in some cases. This slow process stands in stark contrast to the chlor-alkali industry's rapid conversion of salt to chlorine, now occurring at the rate of 40 million tons per year worldwide. Many organochlorines are more soluble in fats than in water, once in the environment, they tend to migrate into living tissues-a process called bioaccumulation. Contaminant levels are multiplied as they move from one level of the food chain to the next. Often, the concentrations of organochlorines found in the tissues of fish, wildlife and humans are thousands of times greater than the levels found in the ambient environment. Because virtually all organochlorines are foreign to nature, most living things have not evolved methods to detoxify and excrete them. Organochlorines are known to cause reproductive, developmental, and neurological impairment, cancer, birth defects, immune suppression, and damage to the liver, kidneys, and other organs. For some organochlorines, these effects are known to occur at unimaginably low doses (as low as a few parts per trillion or even less); others require doses in the parts per million to cause measurable effects. ORGANOCHLORINES IN THE GLOBAL ECOSYSTEM Most of the 40 million tons of chlorine produced each year is converted to organochlorines, either purposefully or as accidental by-products. This production rate far outstrips the slow rate at which organochlorines can be converted back into salts and other forms of inorganic chlorine. The total burden of organochlorines in the environment thus grows each year. As a result, organochlorines can now be detected absolutely everywhere on Earth. They are present in the stratosphere, where they have caused depletion of the earth's protective ozone layer. They migrated into the air and water of the entire planet, even at the North and South poles. And they have accumulated in the tissues of living things, even in the deep oceans and polar regions. Species near the top of the food web bear the greatest burdens. Marine mammals and fish-eating birds and wildlife across the planet have the highest concentrations of organochlorines in their tissues. At least 177 organochlorines have been found in the tissues and fluids of humans in the U.S. and Canada, including adipose tissue (fat), mother's milk, blood, semen, and breath. Organochlorines are passed from one generation to the next through the placenta and breast milk. EFFECTS OF ORGANOCHLORINES IN THE GREAT LAKES At least 168 organochlorines are "unequivocally present" in the water, sediments, and living tissues of the Great Lakes ecosystem, according to the International Joint Commission Science Advisory Board. These include an array of pesticides, industrial chemicals, and by-products from chlorine and organochlorines in paper mills, incinerators, and other industries. Thousands more are presumably present but have not yet been detected, due to limitations in the design and technology of monitoring programs. Organochlorines have been linked to epidemic health effects among 13 species of fish and wildlife near the top of the Great Lakes food web. In every case, the effects involved the ability of the exposed organisms to produce health offspring that developed properly. These effects, which show a remarkably consistent pattern, include infertility, birth defects, embryonic mortality, developmental impairment, and behavioral abnormalities. Great Lakes contamination has caused similar developmental effects in humans. A group of hundreds of infants born to mothers who ate Great Lakes fish were born sooner, weighed less, and had smaller heads than infants from the same community whose mothers did not eat Great Lakes fish. The infants behaved abnormally and, in tests at 7 months and 4 years of age, had difficulty learning because of impairments in short-term memory and other mental functions. The effects were attributed to infant organochlorine exposure transferred from the tissues of mothers who had consumed Great Lakes fish. Each of these epidemics has been associated with exposure to one or more organochlorines. In no case have health effects been attributable to individual chemicals. The documented epidemics have clearly been caused by mixtures of numerous organochlorines. Effects in the Great Lakes are an early warning of effects that may occur across the rest of the planet. Many industrial dischargers release organochlorines directly into the Great Lakes. When facilities near the Lakes discharge organochlorines into the air or put them in landfills, a major portion ends up in the water. The Great Lakes also serve as a sink for organochlorines transported by air from as far as Latin America. Once in the Great Lakes basin, organochlorines are very slow to leave it. Less than one percent of the water in the Great Lakes flows out of the Lakes into the ocean each year. The effects of organochlorine contamination thus show up more quickly in the Great Lakes than in other aquatic ecosystems. But as organochlorines are slowly distributed across the planet, similar effects are likely to occur worldwide. Not only does this problem show up more quickly in the Great Lakes, but even after world society finally stops producing and using organochlorines, the Great Lakes will take a very long time to recover--several generations or more. Faster flushing inland water systems can recover more quickly by transferring their pollution to the ocean, where it is more easily ignored. If action is not taken quickly enough, the Great Lakes ecosystem could be destroyed for generations. Organochlorine pollution is thus of special urgency to the people of the Great Lakes ecosystem. GOVERNMENT RESPONSES TO ORGANOCHLORINE POLLUTION Some of the most infamous organochlorines have already been banned or severely restricted: DDT, PCBs, chlordane, mirex, dieldrin, heptachlor, chlorofluorocarbons, etc. Governments have taken these actions after receiving evidence that contamination and effects had already occurred. These banned chemicals have been the focus of virtually all assessments of trends in contamination levels. Despite reduced inputs of these chemicals following government action, levels of banned organochlorines in the Great Lakes ecosystem have declined more slowly than expected. In some cases, their great persistence and continuing input from external sources have resulted in stable or even increasing levels in the Great Lakes food web. Meanwhile, the thousands of organochlorines that have not been restricted continue to be released in the Great Lakes and elsewhere. Many banned substances have merely been replaced with other organochlorines. Total chlorine production has slowly increased, leading to increased organochlorine production and release, as well. As persistent organochlorines continue to enter the environment, total contamination undoubtedly increases. Continuing epidemics among Great Lakes species offer further evidence that meaningful decreases in total contamination have not occurred. No monitoring programs, however, have attempted to determine trends among the thousands of uncontrolled organochlorines or trends in overall measures of contamination (such as total organically-bound chlorine). Most of the organochlorine compounds present in the environment have not even been identified, much less assessed for historical trends. Enough is known about the persistence and toxicity of organochlorines as a class to justify an outright ban. Only a tiny portion of the many organochlorines in commerce have been subjected to even preliminary hazard assessments, and many more organochlorine by-products and breakdown products remain unidentified and thus unassessed. Regulating organochlorines one- by-one is doomed to failure. A shift of regulatory focus from individual chemicals to the class of organochlorines is necessary. The banning of individual organochlorines over the last two decades has resulted in drastic reductions in inputs of these chemicals to the environment. Now, that strategy must be applied to the entire class of organochlorines. To prevent further continually increasing levels of organochlorine contamination, the manufacture and use of all organochlorines must be phased out. Because all uses of chlorine also produce organochlorines, all uses of chlorine must be phased out as well. For virtually all known uses of chlorine and organochlorines, effective alternatives are readily available. RECOMMENDATIONS U.S. and Canadian governments should implement the following policies to phase-out the production (purposeful or unintended) and use of organochlorines: 1 Acknowledge the severe damage to human and ecosystem health caused by the class of organochlorines. 2 Establish a plan to phase-out the use, export, and import of all organochlorines, elemental chlorine, and chlorinated oxidizing agents (e.g., chlorine dioxide, sodium hypochlorite).1 3 Implement an immediate ban on the introduction of chlorinated organic compounds to any combustion device, including trash incinerators, hazardous waste incinerators, boilers, kilns, smelters, and vehicles. 4 Require major users (industries, armed forces, municipal sanitary districts, etc.) of organochlorines, elemental chlorine, and chlorinated oxidizing agents to submit rapid timetables for the phase-out of these substances. Priority should be given to the following sectors which cause severe organochlorine pollution: A) Pulp and paper--a rapid and complete phase-out of chlorine and chlorine compounds in bleaching and delignification. B) Solvent users--a rapid phase-out of chlorinated solvent use in manufacturing industries including automobile manufacture, metal working, electronics and electroplating. Alternatives include water-based paints, improved housekeeping, replacement of toxic materials requiring solvent washes, and substitution of aqueous, biogenic, or mechanical cleaning methods. C) Chlorinated biocides--a rapid phase-out of chlorinated pesticides, herbicides, fungicides, and slimicides (including those that contain chlorine as a non-biocidal element, such as atrazine and alachlor) in agriculture, wood treatment, forestry, and other uses. Govemment programs should encourage the transition to pesticide-free farming techniques, such as improved crop rotation and diversity, use of natural pesticides, and preservation and introduction of predators that prey on pests. D) Chlorinated plastics. A rapid phase-out of chlorinated plastics, especially for disposable purposes (i.e., plastic packaging). 5 Protect workers and communities now involved in the manufacture of chlorine and organochlorines. Funds and programs should be established immediately to provide compensation, retraining, and placement of workers displaced from such industries and to provide similar assistance to communities now dependent on such industries. The funds for such programs should be derived from the chlorine industry itself. For example, a $100 per ton surcharge on chlorine production would generate approximately $1.2 billion per year in the United States and $110 million per year in Canada at current production rates. The actual design of the program should be established through consultation with representatives of the workers and communities involved. 6 Prohibit the substitution of other halogens and organohalogens (e.g, bromine or fluorine compounds) for chlorine and organochlorines since these classes of compounds also tend to be foreign to nature, toxic, persistent, and bioaccumulative. 1 There may be certain minor but "essential" uses of chlorine for which alternatives have not been developed (e.g., antibiotics). Temporary exceptions to the phase-out will be permitted if it can be proven beyond any reasonable doubt that for a specific use of an organochlorine, all of the following conditions can be met: (a) the use serves a compelling need; (b) no alternatives can be found; and (c) intensive research has been initiated to develop alternatives and eliminate the use in question. CHLORINE AND ORGANOCHLORINES IN THE GLOBAL ECOSYSTEM CHLORINE AND ORGANOCHLORINES IN NATURE Chlorine gas (Cl2)--the elemental form of chlorine--is a human invention; it does not occur naturally. In the form of chloride ions (Cl-), however, chlorine is plentiful in nature. Chloride ions occur predominantly as sodium chloride (NaCI)--sea salt and table salt--and in other metallic chlorides in the earth's crust. Chloride ions do not bond with the carbon atoms that are the basic building blocks of "organic" matter--the substances that comprise or are derived from the tissues of living organisms. Chloride ions circulate constantly through the Earth's oceans and through the blood and other body fluids of almost all living organisms. The chemical behavior of artificially-created chlorine gas is entirely different from that of chloride ions. Chlorine gas is highly reactive. It combines readily with carbon-based material to form a whole new class of chemicals--organochlorines--in which at least one carbon atom is directly bonded to one or more chlorine atoms. Organochlorines are not known to occur naturally in the tissues of humans, vertebrates, [Vallentyne 1989], or any "terrestrial animals." [Neidleman 1986] A number of organochlorines can be produced by other organisms but only in very small quantities. [Neidleman 1986] These organochlorines appear to play important antibiotic and messenger roles and to be delicately regulated by metabolic and ecological balances. [Neidleman 1986] The only organochlorine that occurs naturally in significant quantities is chloromethane, which is produced by marine microorganisms and fungi at the rate of about 4 million tons per year. [SRC 1989a] The simplest of the organochlorines, this substance evidently plays a role in the natural regulation of the ozone layer. [Lovelock 1975] The quantity of chloromethane in the environment at any one time was strictly regulated by its relatively slow production rate and nature's limited capacity to convert it back into chloride ions (through reaction with light and other chemicals in the atmosphere). [Lovelock 1975] CHLORINE AND ORGANOCHLORINES IN INDUSTRY By passing large amounts of electricity through brine--a salt- water solution--the "chlor-alkali" industry converts sodium chloride into chlorine gas and alkali, also called sodium hydroxide (NaOH). This process, known as brine electrolysis, is one of the most energy-intensive industrial processes known. [Schmittinger 1986] First undertaken on an industrial scale in 1893, chloralkali manufacture grew slowly until World War II, after which growth rates averaged as much 8 percent annually. [Verbanic 1990] By 1989, 55 U.S. chloralkali plants were producing 11.6 million tons of chlorine annually. [CI 1989] 13 Canadian plants have the capacity to produce about 1.7 million tons per year. [CIS 1989] World production of chlorine now totals about 40 million tons per year. [Rossberg 1986] Either intentionally or unintentionally, most of this elemental chlorine is eventually incorporated into organochlorines. In the U.S., about 70 percent of all chlorine produced [CI 1989] is combined with petrochemicals to produce some 11,000 organochlorine products (pesticides, solvents, refrigerants, chemical intermediates for the production of inorganic chemicals, etc.). [Braungart 1987] The remaining 30 percent of chlorine is used in its elemental form--for bleaching in the pulp and paper industry, for the disinfection of wastewater and drinking water, or to produce purified metals or metal oxides. [CI 1989, Vonkeman 1991] In these cases, chlorine combines with organic matter (wood pulp, sewage, etc.) to form hundreds of organochlorine by-products. BEHAVIOR OF ORGANOCHLORINES IN THE ENVIRONMENT The properties of organochlorines make them very long-lived in the environment: Most organochlorines are very stable. The chlorine-carbon bond at the heart of these compounds is, in general, a strong bond requiring large amounts of energy to break. Many organochlorines thus persist in the environment, resisting degradation by physical and chemical processes. Organochlorines, with few exceptions, do not occur in nature. Living organisms thus have developed few methods to metabolize them. Organochlorines thus resist breakdown by biological processes. Many organochlorines are more soluble in fat than in water. As a result, they tend to bioaccumulate (migrate from the environment into the tissues of living organisms). The breakdown of an organochlorine is not complete until the chlorine atom has once again been converted into sodium chloride or hydrogen chloride. Because organochlorines are chemically stable and resistant to biodegradation, Nature's ability to convert them back into chloride ions is extremely limited and takes place--with few exceptions--very slowly. "In general, the environmental degradability of heavily chlorinated organic compounds, whether by biotic or abiotic mechanisms, is low," according to one industrial reference. [Rossberg 1986] A report by the Federation of European Chemical Industries echoed this view: The vast majority of these [organochlorine] compounds do not occur naturally, are rather persistent and can harm the environment more or less severely. An important part of the organo-halogen compounds produced may remain in use for a shorter or longer period, but will finally appear in the environment. After sometimes 100 years, the compounds will decompose, releasing their chlorine in some form and producing (directly or indirectly) carbon dioxide from the hydrocarbon part. [CEFIC 1989] Persistence in air Organochlorines released into the air resist degradation by sunlight or other chemicals in the atmosphere. For example, carbon tetrachloride, trichloroethane, and chlorofluorcarbons have atmospheric lifetimes ranging from 25 to 150 years [Howard 1990]. Naturally-occurring chloromethane has an atmospheric half- life of 1.5 years [SRC 1989a]. The pesticide alachlor-- specifically designed to break down more easily than other organochlorine pesticides--can be found in rainwater throughout the Midwestern U.S. in concentrations as high as 4 parts per billion. [Goolsby 1991] Trichloroethylene, which has a half-life of only several months, merely breaks down into other organochlorines, including phosgene, dichloroacetyl chloride, and formyl chloride. [HSDB 1991] When organochlorines do break down in the air, the by-products are often more persistent and more toxic than the original compound. For instance, the pesticide mirex can be broken down by light within weeks; however, the breakdown product-- photomirex--is even more persistent and at least as toxic as mirex itself. [HSDB 1991] The case of trichlorophenol is similar. When exposed to light, it can be transformed into 2,3,7,8-TCDD (a very stable chlorinated dioxin), which is far more persistent and far more toxic than trichlorophenol. [Catabeni 1985] Once released into the environment, 2,3,7,8-TCDD can persist for years or decades. [USEPA 1988] Persistence in water Organochlorines also resist chemical breakdown in water. In pure water, for instance, chloroform and trichloroethane remain intact for 1,850 and 1 million years, respectively. [Jeffers 1989] Chlorinated dioxins, too, are resistant to aquatic breakdown processes, remaining intact for decades. "PCDDs are expected to be very persistent in aquatic media," according to USEPA. [USEPA 1985a] Some organochlorines can degrade slowly in water through hydrolysis or other reactions. Many of these compounds are not soluble in water, however, and they escape from surface waters before such reactions can take place. For instance, a large number of organochlorines are very volatile (i.e., most chlorinated ethanes, methanes, and lower-chlorinated benzenes), evaporating from water resources within minutes or hours of their discharge. Chloromethane, for instance, will evaporate quickly from water, decreasing to 50 percent of its original concentration within 1 day. [SRC 1989a] In addition, volatile organochlorines can attach themselves to suspended particles and sediments, remaining intact in aquatic ecosystems for many years. Many of the less volatile organochlorines are not soluble in water, either. Many non-volatile proganochlorines are more soluble in organic matter than in water, these migrate into living tissues or adsorb onto sediments, where they can persist for decades. Hexachlorobutadiene, for instance, reacts with water with a half-life of only a few weeks [HSDB 1991]; nevertheless, it has been found to accumulate in fish tissues in concentrations thousand of times greater than the concentrations found in ambient water. [HSDB 1991] For all these reasons, breakdown in water does not result in significant overall degradation of organochlorines in the environment. According to one study of groundwater pollution in Milan, Italy, organochlorine contaminants are likely to remain at significant levels for "very many years" despite stringent reclamation efforts. [Cavellaro 1986] At least 19 organochlorines have been identified as common water contaminants throughout the U.S. [Burmaster 1982]; however, the actual total is probably far greater, since only 10 percent of the chemicals in groundwater have been identified. [Connor 1984] For the few organochlorines that do degrade in water, the breakdown products may be more hazardous than the original pollutants. For instance, high molecular weight organochlorines (e.g., chlorolignins) make up a large portion of the organically-bound chlorine in pulp mill effluents. They are generally considered relatively non-toxic and non-persistent. However, they are slowly degraded into lower-weight organochlorines (e.g., chlorinated phenols, guaiacols, catechols) which are quite toxic. [Bonsor 1988] These compounds may then degrade slowly to produce chloroveratroles which may be of even greater longterm toxicity. [Bonsor 1988] Similarly, tetrachloroethylene in groundwater may be slowly degraded (over a period of months) into vinyl chloride, which is itself more persistent and far more carcinogenic than the original compound. [HSDB 1991] Resistance to biodegradation Organochlorines also resist biological breakdown by living organisms. Over thousands of years, living organisms have evolved methods lo metabolize or excrete naturally-occurring chemicals. Because organochlorines are almost completely foreign to nature, however, few organisms have developed processes to break them down. lSAB 19891 Consequently, the biologica transformation of organochlorines into chloride takes place very slowly, if at all. "Halogenated aliphatic hydrocarbons are generally thought to be resistant to biodegradation," according to one reference. [Howard 1990] Similarly, aromatic organochlorines--especially the more highly chlorinated molecules--also resist biological breakdown. [Webster 1990] Those compounds listed by the U.S. Environmental Protection Agency (EPA) as most resistant to biodegradation in sewage treatment plants are all chlorinated or brominated compounds. "The extent of halogenation also influences the relative biodegradability of the compounds (i.e., the more halogens in a chemical compound by weight, the less biodegradation will be in evidence)," EPA writes. [USEPA 1986] Most examples of organochlorine biodegradation involve individual micoorganisms that transform specific organochlorine compounds into other organochlorines. These breakdown products may be more toxic than the original pollutant. DDT, widely regarded as extremely persistent, is actually broken down within weeks into DDE, which then persists for decades, bioaccumulates, and is actively toxic in mammals. [HSDB 1991] As noted above, chlorophenols are metabolized into the more toxic chloroveratroles. [Bonsor 1988] Bioaccumulation Many organochlorines build up in the tissues of living organisms. Because most organochlorines are more soluble in oils and fats than in water, they tend to migrate from the environment into the fatty tissues of living things. For instance, TCDD (the most toxic form of dioxin, also known as 2,3,7,8- tetrachlorodibenzo-p-dioxin), has been shown to accumulate in fish tissues at concentrations up to 159,000 times greater than the concentration in the water in which the fish swam. [USEPA 1988] (This figure is known as a bioconcentration factor.) Highly chlorinated aromatic organochlorines are generally regarded as the most bioaccumulative organochlorines. Bioaccumulation factors for PCBs, hexachlorobenzene, octachlorostyrene, chlorinated dibenzofurans, and tetrachloroazoxybenzene are all estimated at 10,000 or more, according to EPA. [USEPA 1985b] Many chlorinated pesticides--such as DDT, chlordane, mirex, and others--have similarly high bioconcentration factors. [HSDB 1991] Many aliphatic and cyclic organochlorines, because they are so volatile, are regarded as less bioaccumulative. Some aliphatics, however, bioaccumulate substantially. Hexachlorobutadiene, for instance, has been found to bioaccumulate by factors as great as 17,000. [HSDB 1991] Similarly, bioconcentration factors for hexachlorocyclopentadiene have been estimated at up to 1600. [HSDB 1991] Humans occupy a position near the top of the food chain, and their exposures to bioaccumulative organochlorines are thus among the highest of any species. At least 177 organochlorines have been detected in the tissues, mother's milk, semen, breath and blood of the U.S. and Canadian population. (see tables 1.1 through 1.5. - omitted here.) These include the most bioaccumulative organochlorines, such as the dioxins, PCBs, DDT, and other pesticides. However, volatile organochlorines generally not regarded as bioaccumulative also appear to be ubiquitous in human tissues and fluids, including chloroform, trichloroethane, tetrachloroclhylene, and chlorobenzene. Though many organochlorines resist biochemical alteration and excretion, they can be eliminated from the body through mother's milk, blood, and semen. Bioaccumulated organochlorines are thus transferred from one generation to its offspring through these fluids. Infants in utero receive significant doses via cross- placental transfer. Following their birth, they receive even greater doses when nursing. These doses can be many times greater than the original environmental exposures to which their mothers were subject. [Swain 1988] Toxicity The Science Advisory Board to the International Joint Commission on the Great Lakes (IJC) has summarized the nature of organochlorines as follows: There is something inherently nonbiological about halogenated organics (excluding iodinated compounds).... They have been introduced in the last one hundred years into a planetary ecological system that has been in operation for several million years. One does not have to be a biologist to know that random changes introduced into integrated systems have a high probability of being harmful. This statement should be equally obvious to a politician, medical practitioner, or car mechanic... Most synthetic industrial chemicals for which there are toxicological data are known to cause adverse effects.... Chemicals [that] do not occur naturally ... are often persistent, since there are often no natural biological process to metabolize or deactivate them. In contrast, there are natural biological processes to metabolize or deactivate naturally occurring chemicals. [SAB 1989] Organochlorines are widely recognized as a highly toxic chemical class, causing a wide range of health effects in a broad array of species. Because organochlorines are largely foreign to nature, few living organisms have developed methods to detoxify them. [Webster 1990] Many organochlorines thus lead to reproductive failure and infertility; many cause birth defects; some are known to cause embryonic mortality or impair the development of children; some are known to disrupt the immune system; many cause cancer; virtually all damage the liver, kidneys, nervous system, and other organs or systems. According to one industrial reference, "Many, if not most, chlorinated substances can be made to produce an increase of tumors in certain laboratory animals." [Rossberg 1986] Organisms have evolved natural methods to alter and excrete external compounds that occur in nature to avoid the build-up of "foreign" chemicals within the organism. But organochlorines are almost completely alien to nature, and few natural breakdown methods have been developed. Organisms with longer lifetimes (such as mammals) have had few generations in which to alter, detoxify, and excrete organochlorines. Thus the presence of more than 100 organochlorines in the fatty tissues, mother's milk, semen, and blood of humans is not surprising. For instance, humans have no process by which to alter and excrete 2,3,7,8-TCDD. The major enzyme system induced in response to its presence has little or no ability to metabolize it. [Webster 1990] TCDD thus has a half-life in the human body of as much as 29 years. The major pathways by which it is excreted include mother's milk and semen. [USEPA 1988] Many polychlorinated aromatics, including hexachlorobenzene, chlorinated dibenzofurans, and PCBs, are also resistant to mammalian metabolism. [Webster 1990] Some organochlorines mimic naturally occurring hormones or enzymes. For instance, DDT has an estrogenic effect that can lead to feminization, infertility, and developmental impairment. [Fry 1987] Further, chlorinated aromatics induce an enzyme system involved in the metabolism of hormones that affect growth, sexual development, and the detoxification of other chemicals. [Webster 1990] These hormones and enzyme systems function in a naturally self- regulating equilibrium: naturally-circulating hormones induce enzymes which lead to breakdown of the hormones, resulting in relatively stable levels within the body. Because many organochlorines cannot be broken down, however, they can lead to runaway biochemical reactions and a cascade of health effects. [Webster 1990] These effects include birth defects, embryonic mortality, infertility, immune suppression, and the conversion of cancer-causing chemicals into more carcinogenic forms. [Webster 1990, Silbergeld 1987, Silbergeld 1989] GLOBAL ACCUMULATION OF ORGANOCHLORINES For millions of years, natural processes have limited the amount of carbon-bound chlorine in the global ecosystem to only trace quantities. Now, the industrial production of 40 million tons of chlorine per year has severely disrupted this delicate balance. The generation and dispersal of persistent synthetic organochlorines has far outstripped nature's ability to break them down. Meanwhile, the continuing release of persistent organochlorines further disrupts this equilibrium. As a result, organochlorines have built up throughout the biosphere. They can be detected in the air, water, and food web of the global ecosystem. Throughout the United States and Europe, an array of organochlorines can be found in the air, surface waters, and groundwater. Persistent organochlorines--even those not regarded as air contaminants, like PCBs--are also transported long distances on air currents, leading to relatively uniform global distribution. [Travis 1991] Even in the planet's most remote regions--such as the Arctic circle or the Pacific ocean--chlorinated pesticides, PCBs, dioxins, and chlorinated solvents can be found in air, water, snow, and living tissues. [Travis 1991, deLorey 1988, Gregor 1989, Rossberg 1986] Recently, Inuits living in Arctic Quebec-- remote from industrialization--were found to have extremely high levels of organochlorines in their tissues and mother's milk, due to their position at the apex of a short and direct aquatic food chain containing large amounts of marine mammal blubber. [Dewailly 1989] Organochlorines are also ubiquitous in the upper atmosphere. Chlorofluorcarbons, trichloroethane, and carbon tetrachloride are now globally distributed in the stratosphere, where their tendency to react with ozone has resulted in the depletion of 2 to 6 percent of the earth's ozone shield in temperate latitudes and near-absolute depletion of the ozone layer over Antarctica. [UNEP 1989] Because of its persistence, global organochlorine pollution will not be easily reversed. Any further releases of CFCs, for instance, are expected to result in continually increasing levels of stratospheric chlorine. Even if releases were stopped immediately, it would still take sixty years for chlorine concentrations to return to the 1985 level (at which significant ozone depletion occurred over Antarctica). [Hoffman 1988] Similarly, if all PCB exposures could be stopped immediately, it would require approximately 6 generations for the PCBs in the human population to drop below detectable levels, due to the passing of these contaminants from one generation to the next. [Swain 1988] GOVERNMENT RESPONSES TO ORGANOCHLORINE POLLUTION In the 1960s and 1970s, scientists discovered extremely toxic organochlorine compounds building up throughout the worldwide ecosystem. In many cases, these chemicals were linked to health problems among humans and wildlife, including birth defects and reproductive failure, cancer, and neurological impairment. The emergence of this information led governments to ban or severely restrict uses of such organochlorines as DDT, PCBs, dieldrin, endrin, pentachlorophenol, heptachlor, chlordane, lindane, and toxaphene. In the 1980s, the focus began to shift from individual organochlorines to groups of organochlorines and industrial sectors using chlorine or organochlorines. The discovery of worldwide depletion of the stratospheric ozone led to international agreements that will eventually eliminate the production of chlorofluorocarbons, carbon tetrachloride, and 1,1.1-trichloroethane; however, it allows the substitution of other ozone-depleting organochlorines in their place. Some limits have also been placed on the discharge of individual organochlorines compounds in effluents from paper mills and water treatment plants using chlorine for bleaching or disinfection in the U.S., Canada, and Europe. Analyses of regulatory strategies in the U.S. have shown that total discharges and levels of contamination in the environment and human tissues have been reduced only in those cases when the production and use of chemicals have been banned. For instance, tissue levels of the banned organochlorine pesticides 2,4,5-T and DDT in human tissues have declined significantly since their phase-out. [Stanley 1986a] In contrast, strategies that have allowed air or water discharges of chemicals within specified concentrations have merely shifted releases from one environmental medium to another without significant improvement in total contamination of the environment or of human tissues. [Commoner 1990] SHIFTING THE FOCUS: FROM INDIVIDUAL ORGANOCHLORINES TO CHLORINE To date, a number of organochlorines and small groups of organochlorines have been the target of phase-out regulations. But there are approximately 11,000 organochlorine products in commerce. [Braungart 1987] An unknown but possibly greater number of organochlorines are formed as by-products in the manufacture, use or combustion of all organochlorines and in all uses of elemental chlorine. The majority of these organochlorines are discharged into the environment without assessment or approval. Of the many industrial chemicals in circulation, information for preliminary hazard assessments are available for less than 2 percent, and new chemicals are being brought on the market faster than testing programs can catch up. [NRC 1984] Not only are most of the organochlorines discharged without hazard assessments, most have not even been identified. Organochlorines are almost always discharged into the environment as diverse mixtures, the chemical character of which is unknown. As discussed in chapter 3, only a fraction (ranging from 1 to 50 percent) of the organochlorines discharged from paper mills, incinerators, and water treatment plants have been identified. Similarly, most of the organochlorine pollutants that have accumulated in the fat, semen, and eggs of humans, fish, and wildlife remain of unknown identities, as detailed in chapter 2. As a result, adequate information will never be available to regulate pollutants--organochlorines in particular--on a chemical-by-chemical basis. Scientists, environmentalists, and government officials have argued for a pro-active phase-out of the entire organochlorine class rather than reacting after the fact to scientific proof that contamination and environmental effects have occurred. For instance, the chairman of the Science Advisory Board has argued: The general rule is that governments ban chemicals on a one-by- one basis and only when "proof" of adverse effects is found. In the opinion of the Science Advisory Board, this reactive behavior is unwise, unscientific, and immoral.... The time is ripe (in fact, overdue) to end the laissez-faire policy for persistent toxic chemicals, organohalogens in particular. It is neither intelligent nor economically feasible to attempt to control them reactively, one-by-one. An anticipate and prevent policy makes far more sense. [Vallentyne 1989] A report by the Federation of European Chemical Industries came to the similar conclusion that organochlorines will be addressed as a class rather than in isolation: To judge the role of halogenated organic substances, or rather organic chlorine compounds as industrial chemicals, we cannot see them isolated from the role of chlorine as a whole.... One may argue that the only fundamental solution for the environmental problems caused by organohalogenated products and their waste is to drastically reduce their production and restrict their use to closed systems. [CEFIC 1989] The Science Advisory Board has recommended a phase-out of all organohalogens, with exceptions only "in individual cases in which the weight of evidence supports the view that the chemicals in the approved dose do not jeopardize the health and integrity of natural ecosystems." [SAB 1989] The Board's chairman explained that the recommendation for a chlorine phase- out was not only necessary but feasible--even inevitable: Given that organohalogens are inherently harmful to most forms of life, including humans, the GLSAB believes that a systematic phasing out of organohalogens is not only desirable but, with improving knowledge, inevitable. Health concerns, the development of biospherically friendly technologies, and aging infrastructures will act as agents of change.... Based on health defects in the progeny of adults exposed to organohalogens, and recognition of the need for global controls, there may be a general move in Europe and North America toward the phasing out of industrial processes leading, directly or indirectly, to the production of organohalogens. If that proves to be the case, industries using chlorine technologies will be subject to chlorine phase-out policies and regulations in the not-too-distant future....[Vallentyne 1989] To eliminate organochlorine pollution, chlorine production itself must be phased out. As long as chloride is converted to chlorine, contamination of the ecosystem with persistent organochlorines will continue. Organochlorine pollution can be stopped only by going to the root of the problem--eliminating industrial chlorine production. ORGANOCHLORINES IN THE GREAT LAKES "Seven recent reports ... have concluded that toxic chemicals, in large part organochlorines, have impaired and are impairing the health of natural populations of fish, reptiles, birds and mammals in the Great Lakes basin. The concentrations of organochlorines in the wild populations are in the same general range as those in human populations. Because of their short generation times, populations of fish and wildlife may be showing effects that will appear later in human populations." (Vallentyne 1989) ASSESSING CHEMICAL MIXTURES The total impact of the hundreds of organochlorines in the Great Lakes ecosystem has never been fully assessed. The information and tools available to scientists preclude such a complete evaluation: Many organochlorine contaminants presumably present in the Great Lakes ecosystem remain unidentified, due to limitations in analytical methods. Data on toxicology and environmental behavior is available for only a fraction of the chemicals that have been identified. Of necessity, epidemiological studies of Great Lakes humans and wildlife have been limited to the few pollutants that have been thoroughly studied. Data on historical trends in contamination have generally been limited to pollutants that have been thoroughly studied and regulated, as well. Epidemiology is not well-poised to detect subtle or slowly manifested health effects, those that effect the offspring of exposed organisms, those that disrupt relationships among species, or those caused by pollutants for which there is no uncontaminated control group. Despite these limitations, organochlorines have been linked to epidemics of reproductive failure, birth defects, and developmental impairment among at least 14 fish-eating species (including humans). In some cases, levels of specific organochlorine compounds in the tissues of the affected organism have been correlated with the severity of the effect. (see table 2.1. - omitted here) These associations, however, do not prove that the chemical correlated is the sole (or even primary) cause of the effect. In no case have individual chemicals been established as the cause of health effects. Instead, these associations point to certain chemicals as contributing to the effects and--since high levels of one persistent organochlorine are usually accompanied by others--imply that groups of chemicals may be to blame. Great Lakes species are exposed to hundreds of chemicals that cause a diverse pattern of health effects; many can act additively or synergistically to produce a single effect or suite of effects. In real-world ecosystems, actual impairment is almost always caused by groups or classes of chemicals. Indeed, the pattern of epidemic impairment in the Great Lakes, in fact, is consistent with the known effects of hundreds of individual organochlorine compounds. According to the Science Advisory Board, chemical-specific causality is nearly impossible to determine, because individual chemicals do not cause health effects that are unique. Also, in many instances, the health effects caused by contaminants may be similar or identical to those caused by other agents. This phenomenon means that many different chemicals can result in similar health effects. [SAB 1989] 168 organochlorines are "unequivocally" present in the Great Lakes ecosystem, according to the International Joint Commission on the Great Lakes (IJC). [GLWQB 1989] These organochlorines are those listed in the LTC's comprehensive track of 362 pollutants "about whose environmental and human health hazard little or nothing is known." [GLWQB 1989] (see table 2.2 - omitted here) In addition, at least 177 organochlorines have been detected in the tissues and fluids of the U.S. and Canadian human populations. Pesticides, PCBs, industrial chemicals, and by- products of the manufacture, use, or incineration of other organochlorines are ubiquitous in the fat, mother's milk, semen, blood, and breath of the general human population. (see tables 1.1 through 1.5 - omitted here) The National Research Council has noted that toxicity information is available to support hazard assessments for less than 2 percent of the chemicals in commerce. [NRC 1984] Data on accidental byproducts and breakdown products are presumably even less ample. Because of these many unknowns, policymakers and scientists have focused on chemicals whose effects have been clearly demonstrated. In 1985, the IJC identified 11 pollutants "known to be persistent and highly toxic, and known to be present in the Great Lakes ecosystem at levels of concern" [GLWQB 1989] This list was given priority for regulatory actions to reduce contaminant levels. Of these 11 "Primary Track" pollutants, eight are organochlorines: PCBs DDT and metabolites 2,3,7,8-TCDD (dioxin) Dieldrin 2,3,7,8-TCDF Toxaphene Hexachlorobenzene Mirex All but two of these (TCDD and TCDF) were already subject to federal bans or restrictions in the U.S. and Canada. These policies were implemented in the 1970s or early 1980s based on clear evidence of their toxicity, persistence, bioaccumulation, and widespread occurrence. The focus on contaminants whose threat is well-established has diverted attention from other pollutants. Because of their "recognized threat to human health and the aquatic ecosystem," [GLWQB 1987] the Primary Track chemicals have been the subject of virtually all the field research and subsequent regulatory action. According to one reviewer, "Most attention has focused on the 11 critical pollutants' major sources, trends in concentration levels, and additional control strategies." [Colborn 1990] Most of the chemicals present in the Great Lakes have thus been neglected in field investigations. The contribution of the 362 chemicals on the IJC's "Comprehensive Track List" to health effects among Great Lakes species has seldom been investigated. Virtually no information is available concerning historical trends in the contamination level of these pollutants. According to a Science Advisory Board review of all available literature on the effects of persistent toxic substances on Great Lakes species: An immediate and somewhat surprising observation after scanning the list of studies is that only a small number of specific persistent toxic substances (alone or in combination), including those listed in the Great Lakes Water Quality Agreement, have been assessed by in situ or laboratory studies for their effects on Great Lakes species. Most of the diverse Great Lakes aquatic populations have not been studied. These types of studies are indispensable to understand and corroborate the observed functional responses to the ambient Great Lakes environment and to identify the major causal agent(s). [Fitchko 1986] Of course, results are available only for those chemicals and effects that have been investigated. The limited scope of available information concerning organochlorines in the Great Lakes is an artifact of the state of scientific knowledge and government priorities. The available information does not reflect the actual extent of contamination, impacts, and trends. OCCURRENCE OF ORGANOCHLORINES IN THE GREAT LAKES Table 2.2 (omitted here) lists the 168 organochlorines on the IJC's "comprehensive track" of pollutants detected in the Great Lakes ecosystem. These organochlorines include an array of pesticides, industrial solvents and intermediates, by-products of the manufacture, combustion, and use of chlorine and organochlorines, and unusual compounds that may be the result of environmental transformations of other organochlorines. Unquestionably, even this list contains only a fraction of the organochlorines present in the Great Lakes. In a given sample, current analytical technology can identify only those compounds present above a detection limit (usually in the low parts per trillion). Chemicals present in quantities less than this limit remain unidentified. When hundreds or thousands of chemicals are present in quantities less than detection limits, the total amount of unidentified "trace" contaminants may make up the bulk of the total chemical burden. For instance, thousands of combustion byproducts are present in trace quantities in emissions from hazardous waste incinerators, but fewer than 100 have been identified. These unidentified chemicals account for 40 to 99 percent of the total mass of unburned chemicals emitted, according to the U.S. Environmental Protection Agency (EPA). [USEPA 1990a] Moreover, exotic or novel compounds (i.e., byproducts, breakdown products, or metabolites of better known organochlorines) are often difficult or impossible to identify in laboratory analysis. In most cases, the only pollutants that can be identified are those that can be matched to an existing database of chemicals and their behavior within laboratory analytical equipment. As a result, chemicals that are not part of the analytical database usually go uncharacterized. For example, the pesticide chlordane is a mixture of at least 50 individual compounds, many of which have not been identified; as a result, these compounds have not been sought in human tissue analyses [Dearth 1990], and they are presumably not included in the chromatographic libraries used for most identifications. Similarly, the pesticide toxaphene is a mixture of up to 670 individual compounds, few of which have been identified or sought in human tissue samples. [Stanley 1986b] As a result, unknown compounds in biological samples usually outnumber the chemicals that are identified. For instance, Swedish analysts were able to identify less than 5 percent of the total mass of organically-bound chlorine in fish tissues from the North Sea. [Sodergren 1989] A small but unquantified portion of the total pollutant burden in the fatty tissues and seminal fluid of the U.S. human population has been identified [Stanley 1986a; Dougherty 1980]. At least 700 of the compounds in human adipose tissue remain uncharacterized. [Onstot 1987] Chemical analysis of organochlorines in Lake Ontario herring gull eggs was able to identify only 25 to 75 percent of the total organically-bound chlorine present. [Norstrom 1981] Of course, the toxicity of unknown compounds cannot be evaluated. Unidentified organochlorines thus pose an unknown but potentially serious threat to ecosystem integrity. The class of organochlorines shows a clear pattern of toxicity, often at very low doses; there is every reason to suspect that the unknown compounds may be having significant effects on the health of Great Lakes populations. In a report on chlorine use in the paper industry, Environment Ontario has argued that trace unidentified contaminants could pose a threat as great or greater than known pollutants: One further thing is, however, most important. Ninety-seven percent of the total amount of organochlorine from a kraft bleach plant has not been identified as specific substances. Certain subtle toxicants such as chlorinated dioxins have recently been identified in some mill effluents. Although they form an infinitesimally small proportion of total organochlorines..., they could be creating some real problems. The obvious question is: how many other subtle toxicants in bleach plant waste await discovery? [Bonsor 1988. Emphasis in original] Sweden's National Environmental Protection Board came to a similar conclusion concerning their failure to identify the bulk of the organically-bound chlorine in fish from the Norsunndet area of the Baltic Sea: It was found that only a minor part of the persistent amount of EOCI [extractable organically-bound chlorine] in the sediments could be explained by known substances. In addition, there was a larger proportion of unknown, persistent, lipophilic material in the fish populations at Norrsundet than in fish from nonpolluted areas. There is a risk that among this material there are further substances which are already or will become distributed over wide geographical areas. Despite the fact that no biological effects could be associated to this persistent material, its actual occurrence gives cause for concern, particularly with regard to what is earlier known of substances with similar properties. In addition, it is unacceptable that there is a risk that such material attains large-scale dispersal since, in such cases it is impossible to introduce counter-measures to reduce the damage. It is therefore of extreme urgency that methods are developed to reveal whether this large-scale dispersal of persistent substances also causes biological effects. [Sodergren 1989] EFFECTS ON GREAT LAKES FISH AND WILDLIFE Organochlorines have been associated with epidemic health effects in 13 Great Lakes species of fish and wildlife. (see Table 2.1. - omitted here). "All of these animals derive their sustenance from animals in the Great Lakes food web, especially fish," according to one review of health effects among Great Lakes species. [Colborn 1990] Typically, concentrations of highly bioaccumulative organochlorines in the tissues of these species are thousands of times greater than concentrations in the lakes themselves. The effects are truly epidemic. They have not been limited to the immediate areas in which pollution sources are located, although in some cases the most severe effects have occurred in such areas (i.e., alterations in fish community structure near a paper mill discharge on Nipigon Bay [Fitchko 1986]). For the most part, effects among fish-eating species have occurred across large areas of lakes (i.e., Green Bay, southern Lake Michigan) and may even have been basin-wide or lake-wide. Bald eagle reproduction, for instance, appears consistently impaired along the entire perimeter of the Great Lakes, although the most severe population declines persist on the shores of Lake Ontario. The universality of organochlorine contamination and effects in the Great Lakes reflects the dispersion of pollutants throughout the food chain of the entire ecosystem. A recent scientific conference investigated whether these effects could be definitively linked to toxic pollution. The conference, which focused on primary track organochlorines, discussed epidemics of reproductive and developmental failure or impairment among Great Lakes humans, terns, bald eagles, mink, trout, and turtles. The conference came to the following conclusion: There are strong indications of a variety of diseases in some Great Lakes fish and wildlife populations that are causally linked to the presence of persistent toxic substances-- specifically to DDT and metabolites, dieldrin, PCBs, and polychlorinated dibenzo-p-dioxins. [IJC 1989a] Another review surveyed epidemics of reproductive failure from the early 1970s to the mid-1980s in Great Lakes mink, herring gulls, double-crested cormorants, Forster's terns, common terns, caspian terns, and black-crowned night-herons. It concluded as follows: These case histories concerning reproductive dysfunction in populations of fish-feeding mammals and birds formally demonstrate the causal interrelationship between the observed epidemics and contamination of Great Lakes fish with organochlorine chemicals. This formal demonstration is based on a consistency of the evidence relating the characteristics of the observed reproductive pathology to the presence of specific chemicals in the fish and adults and in their progeny and to the experimentally determined toxicological properties of the chemicals. [Gilbenson 1988] In some cases, research has attempted to link specific health effects to exposure to individual pollutants. Often, levels of specific organochlorines (i.e., PCBs, DDE) in an organism's tissues have been associated with the severity of the effect. But Great Lakes species are exposed to hundreds of organochlorine chemicals, many of which cause identical, parallel, or synergistic effects. Only in the case of DDT- related thinning of eggshells have documented health effects been related to individual compounds. [Colborn 1990] New evidence, however, indicates that even this situation may be more complex. Although DDT and metabolites appears to have caused the eggshell thinning, the thinning does not appear to be the primary cause of the loss of eagle reproduction. According to one reviewer, The mechanism of the effect of DDE on productivity of bald eagles was not by eggshell thinning but by some other mechanism. Eggshell thinning was a parallel symptom. Probably this whole field of ecological effects of toxic chemicals... is full of parallel symptoms and we don't know what the full causal chain is for any species in the wild. [Nisbet 1989] The pattern of effects among Great Lakes species reflects exposure to a great number of organochlorines, rather than to specific compounds. For instance, the reproductive and developmental effects that have occurred among a number of species appear to have taken place through metabolic and endocrine disruption caused by induction of enzymes associated with the aryl hydrocarbon (Ah) receptor. [Allan 1991] This enzyme system, which--with minor variations--is common to many fish, birds, mammals, and humans, can be induced by hundreds of different organochlorines. (see table 2.3). For example, the entire class of aromatic organochlorines are inducers of the Ah system; the most toxic forms (i.e., certain dioxins, furans, and PCBs) are the most potent inducers. [GLWQB 1989] Induction of this enzyme system is associated with developmental birth defects, wasting syndrome and embryonic mortality, genetic mutations and congenital birth defects, and cancer promotion. In some cases, the enzymes convert other chemicals (for instance, benzo-a-pyrene) into more toxic and carcinogenic forms). [Webster 1990] In addition, induction of the Ah enzyme system may lead to disruptions in the metabolism of sex hormones leading to infertility, impaired sexual development and behavior, immune suppression, and behavioral changes. [Nebert 1981, Silbergeld 1987, Silbergeld 1989] TABLE 2.3 CHEMICALS THAT INDUCE Ah ENZYMES (PARTIAL LIST) AROMATIC ORGANOCHLORINES Chlorobenzenes Chlorinated phenols PCBs Polychlorinated di benzo-p-dioxins Polychlorinated dibenzofurans Chlorinated naphtalenes Chlorinated terphenyls All other aromatic organochlorines ORGANOCHLORINE PESTICIDES DDT Hexachlorocyclohexane (Lindane) OTHER ORGANOCHLORINES Chlorcyliine Chlorpromazine OTHER COMPOUNDS Benzo-a-pyrene 3-methylcholanthrene Sources: Nebert 1981, Webster 1990. Induction of the Ah enzyme system has been documented in numerous Great Lakes species among which epidemic health effects have occurred: Lake Michigan trout gametes [Binder 1984], Lake Ontario and Saginaw Bay herring gull embryos [Ellenton 1985], embryonic Forster's terns, common terns, and black-crowned night herons from Green Bay [Hoffman 1987], and newborn cormorants from Green Bay. [Allan 1991] In addition, enzyme induction has been hypothesized as a cause of near-total reproductive failure among mink living along the shores of Lake Ontario. [Allan 1991] Induction of enzyme systems is clearly a response to a large group of compounds rather than a single organochlorine. According to Environment Canada: [Researchers] are finding an extremely high degree of correlation between the EROD induction capability of egg extracts and certain measures of developmental toxicity and reprod success in colonial birds. However the correlations between these measurements and levels of any single chemical measured in conventional residue analyses is very poor. [Allan 1991] Similar biological disruptions caused by multiple chemicals and leading to multiple effects include alterations of thyroid function and interference with vitamin A/retinol levels. In each case, again, the effects are not unique to single chemicals but may be caused by chemical mixtures. Diverse groups of organochlorines are known to effect both systems. For instance, DDT, dieldrin, PCBs, dioxins, mirex, and octachlorostyrene are all known to disrupt thryoid function. Both thyroid and retinol disruptions have been documented among numerous Great Lakes species in which epidemic effects have occurred. [Allan 1991] A detailed discussion of all the major epidemic health effects associated with organochlorine exposure in the Great Lakes is beyond the scope of this document. Nevertheless, a few examples may illustrate the extent of the problem. Lake trout From 1965 to 1979, an average of two million lake trout were planted in Lake Michigan each year. Nevertheless, a viable self- reproducing population has failed to establish itself, apparently due to widespread mortality during embryonic and swim- up (new-born) stages. [Fitchko 1986] Researchers found 167 organic chemicals--many of them organochlorines--present in adult trout tissues from southern Lake Michigan. [Mac 1988] PCBs, dioxins, furans and other contaminants were also found in trout eggs from the same area. [Binder 1984] A subsequent study found that fry exposed in the laboratory to PCBs and DDT at the levels found in Lake Michigan had mortality twice that of unexposed fry. [Berlin 1981] Ah system enzymes in Lake Michigan trout gametes were 3.5 to 8.6 times higher than in control groups, and induction was associated with organochlorine contaminant levels, especially PCBs [Binder 1984]. When eggs from Lake Michigan trout were incubated in water from Lakes Huron and Superior (and vice versa), mortality was highest among the Lake Michigan eggs regardless of the water in which they were incubated; the cause of mortality was thus associated with the source of the eggs and sperm, and the researchers pointed to "parentally transferred contaminants." [Mac 1985] PCBs and DDT were elevated in the trout from Lake Michigan and were considered contributing factors but could not fully account for the elevated mortality. [Mac 1985] Subsequent reviewers wrote: The likelihood of separating out the effects of individual chemicals from mixtures is small since the number of permutations and combinations is overwhelming.... Although the evidence strongly suggests a chemical etiology, the responsible chemicals may never be identified. [Allan 1991] The trout's reproductive failure was attributed to exposure to a number of organochlorines. As noted above, the Ah enzyme system had been disrupted in trout gametes, an effect that can be caused by hundreds of organochlorines. [Binder 1984] One investigator summed up: In spite of the planting of a total of 50 million lake trout in Lake Michigan in 1965-1985 and the development of a large population of mature adults, natural reproduction of lake trout was almost nonexistent. Laboratory studies and field verification studies have suggested that chlorinated hydrocarbons, such as DDE and PCBs, along with other chemical contaminants may be contributing factors in the reproductive failure of lake trout, especially in industrialized regions on southeastern Lake Michigan. [Passino 1987] Bald eagles Bald eagles suffered severe population declines throughout North America in the 1950s and 1960s due to DDT-induced eggshell thinning. Since the ban on DDT, populations across most of the continent recovered. "Unfortunately, this was not so in the Great Lakes," according to one review. "In 1986, there were reported to be only 25 nests on the Lake Superior shoreline, 4 on Lake Michigan, 4 on Lake Huron and 12 at the western end of Lake Erie. There were no nests on Lake Ontario." [Colborn 1990] A disproportionate number of bald eagles along Lake Michigan shores are still unable to produce viable young compared to inland populations from the same states. [Colborn 1990] The cause is no longer thought to be a single chemical. One reviewer wrote: A case can be made that PCBs and possibly dioxins and furans contributed to embryonic mortality of bald eagles in the Great Lakes basin. The loss of bald eagle productivity is associated with a suite of clinical symptoms in addition to eggshell thinning, including embryonic and hatchling mortality, failure of eggs to hatch, failure of established mature pairs to nest, adult sterility and excessive loss of young birds.... Levels of organochlorine chemicals in the Great Lakes remain too high for successful re-establishment of bald eagle populations. [Colborn 1989] Organochlorine are also known to have caused "feminization" among bald eagles and herring gulls. Exposure of male birds to DDT and methoxychlor in the laboratory has caused malformed testicles and the development of ovaries. [Fry 1987] Surveys of gulls in areas with significant organochlorine pollution in the Great Lakes, Puget Sound, and Southern California discovered widespread decreases in actively breeding males, unusual female-female pairing, and supernormal clutches of eggs attended by groups of females. [Fry 1987] "Stable breeding colonies of gulls in less polluted areas have not exhibited SNC [supernormal clutches] or female-female pairing," the authors wrote. [Fry 1987] It is notable that dioxins, hexachlorobenzene, other aromatic organochlorines, and the pesticides DDT, heptachlor, chlordane, and toxaphene are also known to result in lowered testosterone levels; mice fed hexachlorobenzene in the laboratory had lowered serum testosterone and developed shrunken seminal vesicles and prostate glands [Haake 1987, Elissade 1979] Gulls, terns, and cormorants A pattern of "chronic impairment of reproduction," [Gilbertson 1989] consisting of embryonic and chick mortality, growth retardation, wasting syndrome, and developmental abnormalities has occurred among numerous Great Lakes colonial bird species: Herring gulls in the lower Great Lakes during the early 1970s; Forster's terns in Green Bay in 1983; double-crested cormorants and Caspian terns in various locations in the upper Great Lakes from 1986 onwards. [Gilbertson 1989] The pattern of effects is consistent with "chick edema disease," which is caused by PCBs, TCDD, and other aromatic organochlorines. [Gilbertson 1989] One group of reviewers summarized the widespread nature of the disease: The disease has been found in a variety of species in a variety of locations by different observers using different study designs. Outbreaks of the disease have occurred at different times and seem only to be related to exposures of developing embryos to high levels of chick-edema active compounds. [Gilbertson 1989] Although researchers have estimated that several PCB congeners are responsible for the majority of the "chick-edema" toxicity, no direct relationship has been demonstrated between tissue levels of PCBs and the frequency and severity of effects. Instead, the effects appear to be caused by a mixture of PCBs, dioxins, furans, and other contaminants. [Allan 1991] Ecosystem and interspecies effects Virtually no information has been gathered concerning the effects of organochlorine pollution on the integrity and structure of the Great Lakes food web. Effects on microorganisms at the base of the food web can have broad and serious consequences for the many species that depend on that food web for survival. A number of organochlorines are known to be toxic to plankton, zooplankton, and other microorganisms. Tests of bacteria and phytoplankton in dilute solutions of organochlorine pesticides, PCBs, and dichlorophenol, for instance, have resulted in decreases in some organisms and increases in others. Such "selective" toxicity can have serious effects on biological diversity. According to the Science Advisory Board, These changes in phytoplankton species composition, although they may not reduce algal biomass, may have important implications for food chain dynamics through selective grazing preferences by zooplankton.... This may result in alterations to the species composition of the zooplankton community and perhaps the fish community. [Fitchko 1986] A few studies have documented such localized effects in the Great Lakes. "The data show PCB contamination in the Great Lakes tends to cause growth reduction in nannoplankton species, including mostly small diatoms and phytoflagellates. Since nannoplankton has been shown to be a major food source for many zooplankton species, the communities forming higher trophic levels would be affected," according to the Science Advisory Board. [Fitchko 1986] Pulp mill discharges in Lake Superior were found to have "decimated the benthic community of the extreme inner part of Moberly Bay of Jackfish Bay in Lake Superior." [Fitchko 1986] PCBs and their metabolites are thought to have affected the Saginaw Bay nannoplankton and zooplankton communities, as well. [Fitchko 1986] Resulting changes in species balance at this level, the Science Advisory Board wrote, "may not be desirable in an ecologically balanced ecosystem and may destabilize food-chain dynamics." [Fitchko 1986] "Few studies have assessed the direct impact of toxic chemicals on fish community structure," according to the Science Advisory Board. [Fitchko 1986] No studies are known that have investigated the impacts of altered species-balance at the base of the food web on fish and wildlife in the Great Lakes or elsewhere. EFFECTS ON HUMANS In 1989, the IJC issued the following warning concerning the threat to human health posed by Great Lakes contamination: We have concluded from wildlife and laboratory animal information that persistent toxic substances in the Great Lakes Basin ecosystem pose serious health risks to living organisms. Sixteen Great Lakes wildlife species near the top of the food web have had reproductive problems or declines in population at one time or another since 1950. In each case, high concentrations of contaminants have been found in animal tissue. Together with available human data, the information leads us to conclude that persistent toxic substances in the Great Lakes environment also threaten human health. [IJC 1990b] The contaminants to which humans in the Great Lakes are exposed are no different from those to which other species are exposed. A total of 177 organochlorines have been detected in the following tissues and fluids of the U.S. and Canadian human populations (see tables 1.1 through 1.5 - omitted here): 108 organochlorines have been detected in human adipose (fatty) tissues; 134 in mother's milk; 29 in blood; 43 in semen; 30 in breath. For the most part, these organochlorines in human tissues are the same ones present in the Great Lakes ecosystem (and in other ecosystems across North America). Again, these may represent only a partial picture of the total organochlorine burden that has accumulated in human tissues and fluids. Despite certain variations, humans are essentially similar in genetic code and metabolic systems to the species in which epidemic health effects have been documented [Muir 1987]. According to a report for Environment Canada, similar effects can be expected to occur in both humans and wildlife, but the larger size and slower reproductive cycles of humans "require more time to observe patterns of effects on the most sensitive life-stage-- the unborn and future generations." [Muir 1987] Linking individual chemicals to human health effects is at least as difficult as linking them to wildlife effects, for the following reasons: There is no uncontaminated control group against which to make comparisons, leading to a failure to detect population-wide effects; Some effects--i.e., cancer and multigenerational reproductive effects--may take up to 30 years to appear; Humans are exposed to thousands of chemicals with identical, additive, inhibitive, or synergistic effects; Subtle changes in development, fertility, behavior, cognition, and immune response are difficult to measure; Suspected effects cannot be confirmed in the laboratory for ethical reasons. As a consequence, little conclusive research is available on the effects of Great Lakes organochlorines on humans. The only major study undertaken to date--published between 1984 and 1990-- compared the development of children born to mothers eating Lake Michigan fish to infants in a control group whose mothers did not eat Great Lakes fish. Mothers who ate about one fish per month gave birth about a week early to babies that weighed less (by about one-half pound) and had smaller head circumferences. The infants showed significant behavioral problems, including jerky, unbalanced movement and increased startle reflexes, decreased interest in novel stimuli, and a greater number of abnormally weak reflexes. [Jacobson 1988] The infants born to fish-eating mothers had an impaired ability to learn. After 5 and 7 months, these infants performed poorly on visual recognition tasks. After four years, the children born to fish-eating mothers the infants showed impaired short-term memory in both verbal and quantitative tests. [Jacobson 1988] One reviewer summed up the effects as follows: The tendency [of infants born to mothers eating Great Lakes fish] to respond to a new stimulus decreased in direct proportion to the level of maternal exposure to contaminants in fish consumption, suggesting a more than ten percent decline in visual recognition memory. This observation suggests an effect of contaminants upon the centers of higher integration in infants secondarily exposed via maternal circulation. [Swain 1988] The authors investigated a correlation of the effects with in utero PCB exposures. Fish-eating mothers had higher concentrations of PCBs in their blood and umbilical cord serum. Further, these levels were correlated with the severity of the cognitive and physical effects in the infants. "The data demonstrate the continuation of a toxic impact received in utero and observed initially during infancy on a dimension of cognitive functioning fundamental to learning," the authors wrote. [Jacobson 1990] Undoubtedly, PCB exposure was associated with the infants' impairment. However, this association did not rule out other chemicals as additional, or even primary causes. Children born to mothers eating Great Lakes fish are almost certain to have elevated levels of the many other organochlorines in those fish. The authors did measure serum levels of DDT, hexachlorobenzene, oxychlordane, heptachlor epoxide, trans-nonachlor, Mirex, and polybrominated biphyenyls; they found no association with the effects they examined. However, no other organochlorines were investigated, including the dioxins, furans, or any other chlorinated aromatics. "Environmental exposures include a mix of highly toxic organic chemical contaminants, such as the dibenzofurans and dioxins, which are present only at trace levels, and therefore could not be evaluated." the authors explained. [Jacobson 1990] Notably, a study of newborn rhesus monkeys exposed to TCDD in the laboratory--but not to PCBs--had strikingly similar results. The offspring of mother monkeys fed extremely low levels of dioxin (from 5 to 25 parts per trillion in their diet) showed subtle cognitive and behavioral impairment. Although there were no obvious physical effects, the infants born to exposed mothers were unusually dependent and, in turn, their mothers treated them as if they were ill or injured. Months later, the exposed young performed poorly in memory and other learning tasks. In peer groups, the dioxin-exposed young were unusually aggressive, initiating violent behavior more often than unexposed monkeys. [Bowman 1989a, Bowman 1989b, Schantz 1986] Several recent reports on the Great Lakes have pointed to large- scale deterioration of health parameters that can be affected by exposure to persistent toxic chemicals, including organochlorines. [Muir 1987, Colborn 1990] While no causality could be demonstrated, the authors noted similarities between human health trends and the effects in wildlife attributed to synthetic chemicals. For example, one report for Environment Canada pointed to increasing rates of infertility, many types of birth defects and chronic neurological conditions, and total cancer incidence (both including and excluding lung and skin cancers)--all since the 1950s. [Muir 1987] In addition, one review found that mean sperm density had fallen by 30 to 50 percent since 1930; about one-fourth of the decline was statistically correlated with the presence of PCBs and other individual organochlorines detected in human sperm. The remainder of the decline could not be associated with specific chemicals. [Dougherty 1980] Despite the paucity of information directly documenting human health effects, there is good reason to be concerned by human exposures to the same chemicals that are causing epidemics among Great Lakes wildlife. The Science Advisory Board summarized: There is...abundant evidence of health effects, particulary in early developmental stages in wildlife populations. Although the human data are limited, it is likely that exposed human populations behave in a similar way to exposed wildlife populations. This phenomenon exists because we share similar ancestries and evolutionary histories. We are exposed to the same toxic chemicals; we accumulate the same chemicals in our bodies, and toxic chemicals often have similar mechanisms of action in humans and wildlife. On this basis, it is reasonable to presume that toxic chemical exposures may have a significant effect on the health of our children at the community and population levels. Because of their shorter generation times, fish and wildlife may truly be what many have suggested: environmental equivalents of miners' canaries. If such should prove to be the case, then we will have doubly jeopardized the lives of our children through the shameful legacies of prenatally impaired health and toxic ecosystems. [SAB 1989] The Board's chairman continued: The concentrations of organochlorines in these wild populations [in which epidemic health effects have occurred] are in the same general range as those found in human populations. Because of their short generation times, populations of fish and wildlife may be showing effects that will appear later in human populations. [Vallentyne 1989] Given the biological similarity between humans and other affected species, this conclusion is hardly surprising. Humans, after all, occupy a position on the food chain that is as high or higher than piscivorous birds and mammals. Human infants, who receive bioaccumulated contaminants cross-placentally or via mothers' milk, occupy an even higher level. Environment Canada summed the situation up as follows: Since both human and wildlife populations are exposed to similar types of contaminants and have many biological similarities (physiological, biochemical, cellular origination) it is not unreasonable to anticipate that at equivalent levels of exposure there could be some similar effects in both groups.... The similarity of the effects across species is striking....While there are only limited data on human health effects available, there is more information on effects in wildlife. Both data sets suggest that developmental effects occur in the offspring of exposed parents rather than in the parents themselves. [Allan 1991] TIME TRENDS IN GREAT LAKES ORGANOCHLORINE CONTAMINATION Claims that toxic pollution in the Great Lakes--organochlorines in particular--has improved significantly cannot be defended by available information. While there have been clear improvements in conventional pollution (oil, grease, fecal coliform), there are insufficient data to support conclusions about contaminant trends for virtually all the organochlorines in the Great Lakes. For many of those organochlorines that have been assessed, levels in the Great Lakes food web are stable or increasing. Determinations of contaminant trends have been almost completely confined to the primary track chemicals. Concentrations in Great Lakes water and sediments of most of the organochlorines that were banned in the 1970s decreased in the decade following their phase-out. [Allan 1991] There is a similar pattern--but with important exceptions--for concentrations of banned organochlorines in the food web; levels of mirex, heptachlor, chlordane, and some congeners of PCBs decreased in the tissues of most species from the mid-1970s through the 1980s. [Allan 1991] However, the decreases of these chemicals have equilibrated--or "flattened out"--in the last five years. The now-stable concentrations continue to threaten the integrity of the ecosystem. "Early decreases in certain persistent toxic chemicals have levelled out above presently acceptable targets, and no clear strategy has been established to achieve further reductions," according to the IJC. [IJC 1989b] Some of the severely restricted organochlorines, however, did not decrease in living tissues. DDT levels in Lake Superior trout, for instance, doubled between 1985 and 1988 [Allan 1991]. Dieldrin in Lake Ontario fish decreased from the 1970s to the early 1980s, but then increased before equilibrating again. [Allan 1991] The most toxic PCB congeners, however, have shown no decrease whatsoever. [Allan 1991] The lack of overall improvement in organochlorine contamination has been attributed to the great persistence of these chemicals in the environment and their transfer from one generation to its progeny, as well as to "inputs from remaining point sources, cycling of contaminants within the aquatic ecosystem, remobilization of sediments, as well as continued inputs to the Great Lakes from atmospheric deposition and leaking hazardous waste sites." [Allan 1991] The chemicals that have been tracked are, with few exceptions, the primary track chemicals--those already identified as serious problems and subject to regulatory restrictions. Data are available for virtually none of the hundreds or thousands of compounds that have not been restricted. As a result, the available information allows an evaluation of the effectiveness of the phase-outs applied to a number of primary track organochlorines. It provides no basis for evaluation of time trends for the entire class of organochlorines. Of the many organochlorines that have not been restricted, there are historical data for only a few. Of these, concentrations in the food web do not appear to have decreased. For instance, "dioxins and furans are widely distributed throughout the ecosystem; based on limited data, concentrations in fish from Lake Ontario have remained relatively constant," according to Environment Canada. [Allan 1991] In human tissues, beta- hexachlorocyclohexane and hexachlorobenzene may be increasing, and sufficient data are not available to assess human tissue trends for other organochlorines, including the dioxins. [Colborn 1990] For most organochlorines, however, there are no data whatsoever to support conclusions about contaminant trends. No information is available concerning trends in food web levels of chlorinated phenols, benzenes, styrenes, toluenes and other contaminants. Even in the present, according to Environment Canada, "wildlife data are available on levels of only about twenty well-known organochlorine contaminants." [Allan 1991] Further, changes in analytical methods over the last 20 years make those data sets incomparable. As discussed above, many chemicals have not been identified at all, and there is thus no current concentration data, not to mention historical data Of course, chemicals that have not been identified cannot be assessed for chemical trends. Since the bulk of organochlorines in the Great Lakes have not been chemically characterized, a comprehensive evaluation of contaminant trends cannot be performed. Without chemical-by-chemical analyses, the only way to assess trends in organochlorine contamination would be to compare measurements of total organically-bound chlorine. Methods to measure this parameter, however, have only been developed in the last five years. There are no comprehensive examinations of this parameter in Great Lakes water, sediments, or tissues at current levels, not to mention historical levels. An historical assessment, then, cannot be performed. Given the fact that paper mills, incinerators, and other sources are known to be continuing the discharge of persistent organochlorine contaminants into the Great Lakes, it is unlikely that total organochlorine contamination is improving. The continued occurrence of organochlorine-associated epidemic health effects is further evidence of the lack of meaningful improvement in total organochlorine contamination. Effects on terns, bald eagles, turtles, mink, and trout have all been documented within the last five years. [Allan 1991] Thus the IJC refers to "the continued and growing dangers posed to living organisms, including humans, by the presence of persistent toxic chemicals in the Great Lakes environment." [IJC 1989b] CHLORINE AND ORGANOCHLORINES IN INDUSTRY: RELEASES AND BY- PRODUCTS About 70 percent of chlorine is used to produce the 11,000 organochlorine chemicals that are used as solvents, pesticides, plastic, refrigerants, degreasers, chemical intermediates for the production of inorganic chemicals, and for other purposes. The remaining 30 percent is used as elemental chlorine (or derivative chlorinated oxidizing agents, such as chlorine dioxide and hypochlorite) in bleaching, disinfection, or metallurgical processes. (see table 3.1. - omitted here) All uses of organochlorines and chlorine contribute to the global accumulation of organically-bound chlorine. In many uses, organochlorine products are released directly and immediately into the environment. In others, organochlorines are transformed by use, treatment or degradation processes. In some cases, their release is delayed by storage or other waste "disposal" methods, such as landfilling. The full impact of a single organochlorine product (i.e., the use trichloroethylene as a degreasing agent) includes releases of both products and wastes during the manufacture, use and disposal of that product. Such releases involve numerous chemicals and take place at different times at diverse locations. Assessing the full impacts of even a single use of a single organochlorine is thus extremely complex. Moreover, numerous organochlorine by-products are formed in virtually all process involving chlorine and organochlorines: all uses of chlorine and chlorinated oxidizing agents, the manufacture of all organochlorines, the combustion of all organochlorines, and some industrial uses of organochlorine products. In every case, these by-products include the most stable, persistent, ubiquitous, and toxic organochlorines (e.g., dioxins, furans, hexachlorobenzene, etc.). Even organochlorine products of lesser persistence and toxicity are associated with these extremely hazardous by-products. Because these by-products are common to virtually all processes involving chlorine/ organochlorines, linking individual products or processes to chemical contamination is virtually impossible. RELEASES OF ORGANOCHLORINE PRODUCTS In many uses, the release of organochlorines to the environment takes place directly. For example, pesticides have been described as "purposeful environmental contaminants" that are deliberately dispersed into the ecosystem. [Metcalf 1987] Only a tiny fraction reaches the target pest, while "the remainder, greater than 99.9 percent, is essentially wasted and enters the environment through air drift and soil runoff, by leaching into groundwater, by entrapment into dust and air currents, and by deposition in rain." [Metcalf 1987] Similarly, the bulk of chlorinated solvents produced are released directly into the air (via evaporation during product use, fugitive emissions, or wastewater discharges). From 60 percent (for tetrachloroethylene) to 85 percent (for dichloromethane) of total amounts of solvents used in industry evaporate into the air at their place of use. [Lawrence and Foster 1987] According to the Federation of European Chemical Industries, From the volatile organo-halogen compounds, like the halogenated solvents, the vast majority of the production will ultimately evaporate into the atmosphere.... [CEFIC 1989] In some uses, organochlorines are released to the environment after a delay or in the form of other organochlorine compounds. For example, polyvinyl chloride used in plastic packaging enters the municipal waste stream, which is often burned. A broad range of organochlorine by-products have been identified in the emissions from incinerators burning chlorinated plastics. [Yasuhara 1986] Some of these by-products will also be captured in incinerator ashes, which are then landfilled, contributing to groundwater contamination. Even the so-called "recycling" of organochlorine products or wastes merely delays or alters the form of their release to the environment. According to the Federation of European Chemical Industries: Successful recycling of such products means that then an amount of chlorine becomes available, for which industry will try to find another use, probably in another organohalogen. So recycling might only result in an increased volume of organohalogens present at any moment. [CEFIC 1989] Because of the number of industries using chlorine and organochlorines and the complexity with which releases into the environment take place, the risks of individual uses of chlorine and organochlorines cannot be separately assessed. Because organochlorines are globally distributed following their release, linking industrial sources of organochlorines to local contamination, exposure, and health problems is even more difficult. Nevertheless, some individual uses of chlorine and organochlorines have been linked to elevated levels of contamination and health problems among communities and workers receiving the most immediate exposures. Examples include the following: Contamination of rainwater and groundwater by the organochlorine pesticides alachlor and atrazine is especially severe in the Midwestern U.S. where use is highest. [Goolsby 1991, NCAMP 1990] Applicators of certain organochlorine pesticides have been found to have high rates of certain types of rare cancers, including soft tissue sarcoma and lymphatic cancers. [Erikkson 1990, Wiklund 1989] 3.5 million U.S. workers experience direct exposures to trichloroethylene; 500,000 to tetrachloroethylene; and 1.5 million to 1,1,1-trichloroethane, according to The National Institute for Occupational Safety and Health. [SRC 1989b, SRC 1989c, SRC 1989d] For each chemical, workers are listed as "populations at high risk." Occupational exposure to organic solvents in general has been linked to neurological disorders, but only very limited epidemiological data are available concerning individual chlorinated solvents. [OTA 1990] Pulp mill discharges have been linked to malformations and population declines among fish populations in the Baltic Sea. [Sodergren 1989] Dioxin and furan accumulation in fish caught downstream from U.S. paper mills poses calculated cancer risks up to 1 in 50, according to EPA. [USEPA 1990b] Workers in chlorine-bleaching pulp mills have shown elevated rates of cancer. According to the International Agency for Research on Cancer, "Several studies of pulp and paper workers have demonstrated increased risks for certain cancer sites, e.g., tumors of the lymphatic and haematopoietic system as well as stomach cancer. An impressive lung cancer excess was found among paper and board mill workers in Finland, but not in studies elsewhere.... It is impossible to link any of the excesses to specific single compounds or mixtures, of which there are a multitude in pulp and paper industries." [Hogstedt 1990] At least 18 studies [Doull 1977, Doull 1980a, Doull 1980b, Cantor, 1987] have linked human cancer to drinking chlorinated drinking water. A 1988 study found that non-smokers drinking chlorinated water for 60 years had bladder cancer rates 4 times greater than a control group that drank unchlorinated water. [Cantor 1987] "Analytical case control studies have shown a modest increase in risk of bladder cancer and colon cancers with relatively long-term exposure to chlorinated drinking water," according to one review. [Murphy 1990] Chemical workers exposed to vinyl chloride have exhibited elevated levels of brain cancer and other cancers. [HSDB 1991] Vinyl chloride is considered a known human carcinogen. BY-PRODUCT FORMATION Chlorine is an extremely reactive substance that tends to combine almost immediately with organic or other material with which it comes in contact. It acts as a powerful oxidizing agent, bonding with available electrons in organic matter or other materials. Chlorine's reactivity accounts for its uses. As a bleach, it reacts with and destroys the natural organic molecules that cause stains or unwanted color. As a disinfectant, it destroys living organic molecules. In chemical manufacture, chlorine replaces one or more hydrogen atoms bonded to carbon in petroleum-based chemicals. Chlorine-carbon bonds tend to be stronger than chlorine-hydrogen bonds, leading to organochlorine products that are often more stable, more persistent, less flammable, and more toxic than their unchlorinated relatives. As a result, organochlorines are used extensively as coolants, solvents, plastics, and biocides. Some organochlorine products are less stable; these tend to be used as chemical intermediates and in other reactive uses. Due to elemental chlorine's great reactivity, its reactions with organic matter cannot be easily or fully controlled. In all uses of elemental chlorine--bleaching, disinfection, metallurgical processes, and the manufacture of organochlorine products-- unwanted organochlorine by-products are formed. In addition, the incineration of organochlorines and some uses of organochlorines also generate a large number of organochlorine by-products. These by-products include the organochlorines of greatest persistent and toxicity--the chlorinated dioxins, furans, PCBs, and hexachlorobenzene. Even the least toxic organochlorines appear to give rise to the most ecocidal by-products at some point in their lifetimes. Processes in which these by-products have been identified are listed in table 3.2 (omitted here. CHLORINE MANUFACTURE The electrolytic production of chlorine requires careful purification of raw materials and equipment surfaces. [Schmittinger 1986] Little or no organic material is present, except as trace contaminants, as relatively stable plastic materials, or as graphite electrodes in some electrolytic cells. [Schmittinger 1986] Nevertheless, organochlorine by-products are produced in this carefully controlled process. Octachlorostyrene, hexachlorobenzene, and hexachloroethane have all been identified as wastes from electrolytic chlorine production. [HSDB 1991, Verschueren 1983] Polychlorinated dioxins have also been identified in graphite sludges from Swedish chlor-alkali plants. [SNEPB 1990] ELEMENTAL CHLORINE USE The reaction of chlorine with organic matter produces an extremely broad spectrum of organochlorines. In pulp mill bleaching, water treatment, and metallurgical processes, these by-products include the most persistent, toxic organochlorines. Pulp and paper Hundreds of organochlorine by-products have been identified in the effluents from mills that use elemental chlorine to bleach and delignify pulp. (see table 3.3 - omitted here). These by- products include a range of mutagenic and carcinogenic compounds as well as reproductive and developmental toxicants [Bonsor 1988]. Only a small fraction of the total organically-bound chlorine in pulp mill effluents have been accounted for by chemical-specific analyses. An estimated 80 percent of the total consists of high molecular-weight organochlorines that are not amenable to chromatographic analysis. Unidentified low- and medium-weight organochlorines account for another 10 to 17 percent, leaving only 3 percent composed of identified compounds. [Bonsor 1988] The many organochlorines found in the bleaching process are distributed to wastewater discharges, water treatment sludges, air emissions, and the paper products themselves. Pulp mill sludges have been found to contain a broad range of organochlorine compounds, including the chlorinated dioxins. [Mantykoski 1989] Organically-bound chlorine typically composes as much as 4 percent of the sludge. [Mantykoski 1989]. The sludges are usually disposed of directly on land or through incineration. By-products identified in emissions from pulp mill sludge incinerators include the chlorinated phenols, catechols, guaiacols, benzenes, biphenyls (PCBs), dioxins, and furans. [Mantykoski 1989] Bleached paper products contain organochlorines as well. PCDDs and PCDFs have been identified in the low parts per trillion in diapers, cigarette paper, tampons, coffee filters, cosmetic tissues, and bleached milk cartons. [Rappe 1990b] Environment Ontario estimates that approximately 2 percent of the organochlorines formed in a bleaching plant remain in the pulp product, leading to total organochlorine concentrations of as much as 1 percent in bleached pulp. [Bonsor 1988] "However, data on organochlorine content of pulps is very sketchy and unpublished, since there was no interest in it until recently, and there are as yet no accepted testing protocols," the report noted. [Bonsor 1988] In addition, detergents, liquid soap, and tall oil prepared from bleached pulp contain dioxins and furans in concentrations up to 447 parts per trillion, measured as toxic equivalency factors relative to the toxicity of 2,3,7,8-TCDD. [Rappe 1989b] No other organochlorines have been investigated in these products. The use of chlorine dioxide and other chlorinated oxidizing agents produces a similar range of by-products. Chlorine dioxide substitution allows lower total chlorine input and a consequent lowering of discharges of total organically-bound chlorine; however, the chlorine in chlorine dioxide appears to bind to organic matter as readily as elemental chlorine. The replacement of 70 percent of free chlorine with chlorine dioxide in a pulp mill reduces discharges of TOX (total organically-bound halogens) by about 50 percent [Bonsor 1988]. Water treatment A diverse array of organochlorine by-products has also been detected in drinking water and wastewaters treated with chlorine, chlorine dioxide, or other chlorinated oxidizing agents. According to one review: Almost everyone drinks chlorinated water every day because drinking water needs disinfection and chlorine is both inexpensive and effective. Unfortunately, the organic compounds found in natural waters, particularly surface water, react with chlorine. Hundreds of chlorination by-products are then produced, some of which are toxic and apparently carcinogenic. [Johnson 1990] A similar array of by-products is formed when drinking water, sewage treatment plant effluents, and power plant effluents are chlorinated. [Stevens 1990] As with pulp mill effluents, only a fraction (approximately 25 to 50 percent) of the total organically-bound chlorine in chlorine-treated water has been identified. [Amy 1990, Ventresque 1990] Significant amounts of the uncharacterized portion are non-volatile compounds, which are often regarded as more persistent and toxic than volatile organochlorines. [Jolley 1986, Amy 1990] The compounds detected include a wide range of chlorinated methanes, ketones, acids, phenols, dibenzofurans, phenoxyphenols (also called pre-dioxins), and other complex compounds. (see table 3.4. - omitted here) Notably, one study detected the extremely toxic chlorinated dibenzofurans in chlorinated drinking water. [Rappe 1989] The congener pattern resembled that found in other waters treated with chlorine, including pulp mill effluents. The authors wrote: The pattern identified in this report...could be called the chlorine pattern. For the tetraCDFs it consists of the same isomers as the pulp bleaching pattern. However, the chlorine pattern also contains higher chlorinated PCDFs, but no PCDDs. [Rappe 1989] Metallurgical processes Dioxins, furans, hexachlorobenzene, and octachlorostyrene have been identified as by-products in the emissions from nickel and magnesium production processes that use elemental chlorine as a catalyst, intermediate, or precipitating material. [Oehme 1989] The emission rate of hexachlorobenzene from a magnesium factory in Norway has been estimated at 7 kilograms per week. [Oehme 1989] High concentrations of PCDFs were found in fish tissues caught near a nickel refinery in Norway. [Oehme 1989] Because temperatures in the metallurgical processes were as low as 150 degrees C, the authors hypothesized that the metals had a catalytic effect, speeding the formation of dibenzofurans with chlorine in the 1,2,3,7 and 8 positions. They also noted however, that "direct chlorination" may have played a significant role in by-product formation. [Oehme 1989] COMBUSTION OF ORGANOCHLORINES When organochlorines are burned, a full spectrum of by-products are produced. In theory, a properly designed and operated incinerator is intended to convert organochlorines to hydrochloric acid, carbon dioxide, and water. However, real-world combustion systems never take this reaction to completion. According to EPA: The complete combustion of all hydrocarbons to produce only water and carbon dioxide is theoretical and could occur only under ideal conditions.... Real-world combustion systems ... virtually always produce PICs [products of incomplete combustion], some of which have been determined to be highly toxic. [USEPA 1990a] EPA estimates that these PICs--new chemicals actually formed in the incineration process--number in the thousands, though only about 100 have been identified to date. [USEPA 1990a] The most comprehensive research burns have identified no more than 60 percent of the total mass of unburned hydrocarbons in incinerator stack gases. [USEPA 1990a] Most field tests have had far less success in identifying PICs emitted. The bulk of the compounds thus remain of unknown character. [USEPA l990a] In laboratory incineration tests, more than 100 organochlorine PICs have been identified as by-products of the combustion of methane with a chlorine source. The author hypothesized that the chlorinated alkanes, alkenes, and aromatics--including the dioxins, furans, and PCBs--were involved in a single set of equilibrium reactions common to all incineration processes with chlorine present. [Eklund 1988] PICs identified in emissions from incinerators burning organochlorine wastes include chloromethanes, chloroethanes, chlorobutanes, chlorohexanes, chlorononanes, chlorodecanes, chloroethers, chlorobenzenes, chlorophenols, PCBs, dioxins, furans, hexachlorobenzene, and hexachlorobutadiene, according to six reports written by or for EPA. (see table 3.5. - omitted here) Emissions from garbage incinerators burning chlorinated wastes produce similar by-products. According to one review, The major obstacle to construction of new MSWI [municipal solid waste incinerators] is that incineration produces several hundred stable and toxic compounds, including polychlorinated dibenzodioxins. These compounds are always present at parts per million concentrations in all MSWI units, both in the fly ash formed during combustion and in the stack emissions. [Hutzinger 1986] A British review offered the following summary: Comprehensive tests have established that all waste incinerators, independent of type of incinerator or waste composition, are likely to produce all of the possible 75 PCDD and 135 PCDF isomers and congeners as well as about 400 other organic compounds. [UKDOE 1989] These organochlorine PICs form as products of diverse and unpredictable reactions that take place both in the furnace and the cooler zones of an incinerator (the smokestack, pollution control devices, etc.). In the real world, localized and short- term variations from ideal combustion occur constantly. These transient departures from ideal conditions may decrease the destruction efficiency, increasing releases of both unburned wastes and PICs. According to one analysis, deviations from intended combustion conditions usually are a consequence of a rapid perturbation in the incinerator operation resulting from a rapid transient in feed rate or composition, failure to adequately atomize a liquid fuel, excessions in operating temperature, instances where the combustible mixture fraction is outside the range of good operating practice, or inadequate mixing between the combustibles and the oxidant... The amount and composition of PICs will depend in a complex and unpredictable way on the nature of the perturbation. [USEPA 1989] Such transient variations cannot be prevented in real-world incinerators. Changes occur constantly in the rate and type of waste fed, temperature, pressure, mixing, and meteorological conditions. Higher chlorinated PICs are also thought to form in the "cooler downstream regions of the incinerator" due to "relatively slow recombination reactions" of radicals escaping the combustion zone. [Dellinger 1988] Despite high temperatures, then, incinerators serve to manufacture organochlorines as well as destroy them, due to the formation of PICs during constant transient upsets and during the cooling of combustion gases in smokestacks and pollution control devices. MANUFACTURE OF ORGANOCHLORINES Similarly unpredictable and unpreventable reactions also take place when chlorine is combined with hydrocarbon feedstocks to manufacture organochlorine products. Despite a high degree of control over production conditions including material purity, temperature, and pressure, transient variations occur during chemical manufacture just as they do during incineration. As a result of such transient "upsets," the production of organochlorines always results in the formation of by-products. According to one EPA report, The manufacture of halogenated organic chemicals results in the formation of small amounts of undesirable side reaction byproducts. These contaminants may be contained in the product chemical, separated into a processing step residue, or lost to the air or wastewater as a pollutant. [Lee 1987] The production of specific organochlorine products requires a very narrow range of operating parameters. Deviations from these parameters result in unintended reaction products. For example, the production of methylal chloride requires near-perfect conditions: Proper mixing of the components by the inlet jet is a prerequisite to obtaining a high yield of methylal chloride; reaction is so rapid that high local concentrations of chlorine cannot be dissipated, leading instead to the production of more highly chlorinated products. [Rossberg 1986] The chlorination of methane--one of the simplest of all organochlorine manufacturing processes--also requires a narrow range of conditions: In the [temperature] region of commercial interest--350 to 550 degrees C--the reaction proceeds very rapidly. If a certain critical temperature is exceeded in the reaction mixture (ca. 550-700 C, dependent on both the residence time in the hot zone and on the materials making up the reactor), decomposition of the metastable methane chlorination products occurs. In that event, the chlorination leads to formation of undesirably byproducts, including highly chlorinated or high molecular mass compounds (tetrachlorothylene, hexachloroethane, etc.). [Rossberg 1986] While production units can generally be maintained within these parameters, local and transient variations do occur. As a result, by-products are formed in the real-world production of all organochlorines. No attempt has been made to assess fully the quantities or identities of by-products in products and wastes from organochlorine manufacture. No attempt has been made to estimate the quantity of unidentified pollutants, either. As noted above, only a fraction of the organochlorines formed in bleaching, water treatment and combustion has been identified. Presumably, it is no less difficult to identify trace amounts of the many by- products that occur in chemical manufacturing wastes and products. Only a portion of chemical manufacturing processes have been subject to any by-product assessment whatsoever. According to a comprehensive EPA review on the formation of dioxins in manufacturing process, "Much of what is known about the formation of PCDDs and PCDFs has been derived from investigating manufacturing processes for chlorinated phenols.... Identification of sources of these compounds will aid strategies to protect the public from exposure to these chemicals." [Lee 1987] A recent study noted that "the present knowledge about annual emission rates and sources [of PCDDs/PCDFs] is not sufficient to explain transport mechanisms and levels found in the environment, which indicates that PCDD/PCDF are produced by additional processes not known at the moment." [Oehme 1989] By-products from some processes have been identified, however. Although the quantities of individual by-products varies from process to process, certain by-products have been detected in the manufacture of seemingly diverse organochlorines--from the simplest chlorinated aliphatics to the more complex chlorinated phenolic and aromatic chemicals. These by-products include the most stable, persistent, and toxic organochlorines: dioxins, furans, PCBs, hexachlorobenzene, and octachlorostyrene. These are the same by-products that have also been detected in all processes that use elemental chlorine. According to EPA's review of the formation of dioxins as by- products in the manufacture of other chemicals, PCDDs and PCDFs are formed from a wide variety of chemicals, involving complex reaction pathways.... 135 PCDF and 75 PCDD isomers are theoretically possible.... The large number of isomers is one of the reasons for the complexity and difficulty in the analysis and determination of dioxins and furans [as impurities in other organochlorines]. [Lee 1987] Chlorinated dioxins are known or suspected by-products in the production of 104 pesticides, including many organochlorine pesticides and a number of organophosphate pesticides (e.g., parathion) that are manufactured with organochlorine intermediates. [Esposito 1980, PTCN 1985] In addition, EPA has identified 53 commercial industrial chemicals "known or suspected" to be contaminated with polychlorinated dioxins. This list includes the chlorinated phenols, chlorobenzenes, chloroanilines, chloronitrobenzenes, and a number of non- chlorinated chemicals made from organochlorine intermediates. [Esposito 1980] (see tables 3.6 and 3.7. - omitted here) These stable aromatic by-products have also been found where they were least expected, such as in the simple short-chain organochlorine solvents. Dioxins and furans have been detected in commercial chloroethanes and chloroethylenes [Heindl 1987], which are used widely as solvents and in the production of polyvinyl chloride. Those products with detectable levels included trichloroethylene, 1,2- dichloroethane, epichlorohydrin, and hexachlorobutadiene. [Heindl 1987] Individual dioxin and furan congeners were present in concentrations ranging from 13 to 425 parts per trillion. The authors offered this conclusion: These results suggest that the synthesis of short-chain chlorinated hydrocarbons can lead to PCDD/PCDF formation. [Heindl 1987] Hexachlorobenzene (HCB) has also been identified as a consistent contaminant in processes that involve organochlorines or elemental chlorine. HCB occurs as a by- product in the manufacture of all chlorobenzenes, pentachlorophenol, hexachlorocyclopentadiene, pentachloronitrobenzene, vinyl chloride, and tetrachloroethylene [Rossberg 1986, USEPA 1985a]. It is also formed in the electrolytic production of chlorine [HSDB 1991] and in the incineration of chlorinated wastes. [USEPA 1989] HCB is also a known or suspected by-product in the manufacture of 20 pesticides, including the widely-used pesticides atrazine and simazine. [Verschueren 1983] (see tables 3.8 and 3.9. - omitted here) Quantities of hexachlorobenene produced may be large. In the manufacture of tetrachloroethylene, for instance, from 1 to 7 percent of the total output is composed of hexachlorobenzene, hexachlorobutadiene, and hexachloroethane. [Rossberg 1986] Commercial grade pesticides have been found to contain as much as 5000 parts per million HCB. [PTCN 1985] Hexachlorobenzene itself has been found to contain dioxins and furans at concentrations greater than 200 ppm. [Esposito 1980] Given the similarity of the dioxins and HCB and the occurrence of dioxin as a by-product in HCB itself, the presence of hexachlorobenzene in any product or process points to the likely presence of dioxins, as well. According to one review: Hexachlorobenzene, oclachlorostyrene, and other highly chlorinated compounds are formed under similar conditions as PCDD/PCDF, and their presence in the emissions of a technical process should therefore be a good indicator for reaction mechanisms which may also create PCDD/PCDF. [Oehme 1989] This group of highly chlorinated, stable, persistent, and toxic by-products appear to form in the manufacture of all organochlorines, all uses of elemental chlorine, all combustion sources of organochlorines, and some uses of organochlorines. Even the simplest aliphatic organochlorines produce these complex byproducts. USE OF ORGANOCHLORINES Many organochlorines are used in industrial environments conducive to chemical transformations. For instance, pentachlorophenol is used to treat wood at elevated pressures and temperatures. Under such circumstances, organochlorines can decompose and recombine to form an array of new organochlorines. Chlorinated dioxins and furans have been identified as by- products when pentachlorophenate wood preservatives are heated slightly, to temperatures similar to those used in pressure treatment. [Rappe 1978] Dioxins and furans have also been identified in stack emissions and wastewater effluents from Canadian oil refineries that use organochlorine compounds to regenerate spent catalysts. Dioxins and furans containing four, five, six, seven, and eight chlorine atoms were detected in effluents at concentrations ranging into the high parts per quadrillion. [Thompson 1990] Chlorinated dioxins and dibenzofurans have also been detected in emissions from combustive uses of organochlorine solvents. For instance, dioxins were detected in tailpipe emissions from automobiles burning fuel with organochlorine additives. [Marklund 1990] Significant dioxin releases have also been identified from secondary copper smelters reclaiming PVC-coated wire. [USEPA 1987a, USEPA 1987b] By-products have also been found in more surprising processes. For example, the most hazardous organochlorine by-products may be formed when solvents are used as degreasers. According to one study, even the simplest aliphatic organochlorine solvents are converted in alkaline environments into aromatic organochlorines. By-products detected when trichloroethylene was combined with sodium hydroxide included hexachlorobenzene, octachlorostyrene, octachloronaphthalene, dioxins, and furans. [Heindl 1987] The authors noted, "It should be pointed out that trichloroethylene in alkaline medium is used occasionally in an industrial process: for the degreasing of metals, a combination of trichloroethylene, alkaline cleaners, and emulsifiers is used at elevated temperatures." [Heindl 1987] Limited information is available concerning byproducts formed when organochlorines are used in the production of non- organochlorine chemicals. However, organochlorine by-products are known to be formed in these processes, as well. USEPA's list of commercial chemicals with known or suspected dioxin contamination includes 17 non-chlorinated products made from chlorinated intermediates. (see table 3.6 - omitted here). The list of pesticides with known or suspected dioxin contamination also includes a number of nonchlorinated pesticides (i.e., parathion). (see table 3.7. - omitted here) A report for the European Commission pointed to the formation of organochlorine by-products in all uses of organochlorine intermediates: Industrial representatives often state these types of processes have little relevance to the chlorine problem.... Losses and by- products always occur and chlorine-containing emissions and wastes cannot be avoided. Even minor percentages can be meaningful given the large volume of production and the nature of the substances. [Vonkeman 1991] In summary, a large number of processes involving chlorine and organochlorines have been assessed; they have been found consistently to result in the formation of a variety of by- products, including the most toxic and persistent organochlorines. A large number of processes remain unassessed, but the formation of by-products in all uses of chlorine, the manufacture and combustion of all organochlorines, and some organochlorine uses appears to occur. Dioxins, furans and hexachlorobenzene appear to be universal contaminants when chlorine is manufactured and used and when organochlorines are manufactured and burned (as well as in many cases when organochlorines are used). Any strategy to stop emissions of the most toxic and persistent organochlorines, then, must address the entire class of industrial processes that use chlorine or subsequently produced organochlorines. A ban on processes that produce such extremely hazardous by-products would, of necessity, involve a prohibition on the use of elemental chlorine in industrial processes, a prohibition on the manufacture of all organochlorines, and a ban on the introduction of chlorine and organochlorines to combustion units, including incinerators. ECONOMICS OF THE CHLORINE PHASE-OUT IMPLICATIONS FOR WORKERS AND CORPORATIONS As noted in Chapter 1, the IJC's Science Advisory Board has recommended a phase-out of organochlorines and other organohalogens. Despite repeated claims by some industries that toxic substances are necessary to economic productivity and health, the IJC has argued that the environmental and health effects of persistent toxic substances are far more costly than the expense of implementing alternatives: The technology either exists--or can, with very few exceptions, be developed at some cost--to replace (or control in the interim) the use of persistent toxic substances. Sufficient information is now known for society to take a very restrictive approach to allowing persistent toxic substances in the ecosystem and to declare such materials too risky to the biosphere and humans to permit their release in any quantity. They result in implications far beyond conventional measures of long-term net economic costs...." [IJC 1989b]. IMPLICATIONS FOR INDUSTRIES THAT USE CHLORINE In many cases, changes in industry to comply with the chlorine phase-out will cause little economic dislocation. For instance, in the pulp and paper industry, chlorine-free alternatives are readily available. Production of unbleached paper, prolonged pre- bleaching, improved preparation and choice of woods, and use of oxygen, ozone, hydrogen peroxide, and other chlorine-free bleaching methods can produce quality products without chlorine. [Dillner 1990, Bonsor 1988, Sixta 1990] Such changes will, of course, require some capital investment, but they can also produce long term savings through reduced chemical costs and other efficiencies. In North America, if the U.S. and Canadian governments establish a rational coordinated time-table for a phase-out of chlorine based bleaching, neither country's pulp and paper industry need suffer a net loss of markets or jobs. In fact, facilities that produce a portion of their product for the world market would likely see a net gain. Alternatives to organochlorine solvents are already being introduced in the automobile, electronics, and aerospace industries. Water-based alternatives have replaced chlorosolvent paints and dyes. Better housekeeping, process changes, mechanical cleaning methods, and use of aqueous or biogenic solvents have made chlorinated solvents unnecessary. According to the Office of Technology Assessment, such changes result in reduced costs and improved productivity. [OTA 1986] Similarly, chlorinated pesticides can be eliminated in agriculture without diminished productivity. According to a 1989 study by the National Research Council, reduced use of synthetic pesticides can actually increase yields and lower costs for farmers. [NRC 1989] Alternatives include better crop rotation and mixing, introduction and preservation of natural predators that prey on pests, and use of natural pesticidal chemicals. [NRC 1989] Government programs that now apply financial pressure to farmers to use pesticides and maximize short-term yields should be reformed to provide incentives for farmers to forego use of pesticides-organochlorine pesticides in particular. Alternatives are also available for chlorinated plastics, chemical intermediates, and blowing agents and for elemental chlorine in water treatment. For instance, glass, paper, metals, and non-chlorinated polymers can replace all uses of polyvinyl chloride. Ozone treatment is considered a more effective disinfectant for drinking water supplies and for waste water than chlorine, chlorine dioxide, or chloramine. [Moser 1990] (In some cases, drinking water delivery systems would need redesign.) Other alternatives to chlorination include, in many cases, no treatment whatsoever and reduction and prevention of wastewater discharges through water conservation measures, such as closed- loop systems. The most effective alternative, of course, is to prevent contamination of water supplies in the first place through various measures, such as dry sewage systems. [Costner 1986] Alternatives to chlorinated intermediates in the manufacture of other chemicals also exist. For instance, phosgene in the manufacture of resins can be replaced by dimethyl sulfate and dimethyl carbonate; chlorohydrins in propylene and ethylene oxide can be replaced by metallic catalysts; and epichlorohydrin in the production of epoxy resins and olefins can be replaced by electrochemical oxidation with metal catalysts. [Costner 1989] In some cases, the shift to chlorine-free alternatives will add to the costs of production. In many others, it will yield a substantial, long term savings. In all cases, however, this shift will not jeopardize the survival of the industries that use chlorine and organochlorines. REACTION OF CHLOR ALKALI CORPORATIONS In those industries that manufacture chlorine and organochlorines, the chlorine phase-out will be of far greater economic significance, causing major economic dislocations. The U.S. chlor-alkali sector is described as a "$3 billion per year" industry. [Verbanic 1990] U.S. and Canadian producers are listed in tables 4.1 and 4.2 - omitted here. Environmental pressure has already led to downturns in the chlor-alkali industry. Reductions in certain uses of chlorine (i.e., CFCs, pulp and paper, banned pesticides) have resulted in lost markets, declining growth, and lost jobs. Chlorine demand grew by only 0 to 1 percent through 1990, and analysts predict stagnant demand and prices through the next decade. [Hoffman 1990b] Chlorine contract prices tumbled at least 35 percent between 1986 and 1990. [Gilges 1990] Numerous plant closures and consolidations have resulted, and more can be expected in the future. According to one market report, "as many as eight chlor- alkali plants in the U.S. are expected to close in the next five years as a result of high operating costs and the loss of chlorine end-use outlets." [PPW 1990] The chlor-alkali industry clearly recognizes the trend away from uses of chlorine, but it is striving to protect its markets and capital by increasing public relations, fighting further regulation, and expanding markets where environmental regulations are less stringent. The Chairman of Occidental Chemical, for instance, recently argued that the "survival of the chlorine industry is directly linked to the survival of its key markets in what is becoming an increasingly hostile environment for chlorine-based processes." [Hirl 1990] He urged the industry to become "more adept at communicating chlorine health, safety and environmental information...or be swept away with the consequences." The president of the Chlorine Institute is preparing to "overcome negative images and concerns... even though some are unfounded, outdated, and ill-conceived." [Verbanic 1990] In addition, the industry has begun to expand its markets by exporting more organochlorines--especially ethylene dichloride and vinyl chloride, the precursors for polyvinyl chloride--to nations with less stringent regulations. Prime targets for new PVC factories include Brazil, Mexico, Venezuela, Nigeria, the Pacific Rim, and the Middle East. [Endo 1990] Organochlorine pesticides banned or unregistered in the U.S., Canada, and Europe (i.e., chlordane, lindane, haloxyfop, etc.) continue to be manufactured and exported to developing nations, as well. At the same time, some alkali producers are investing in new ways to produce alkali without producing chlorine. Because most alkali markets are increasing while chlorine growth has stagnated [Christaens 1990], alkali producers are looking for alternative production processes. Several have invested in technologies that produce alkali from trona ore without chlorine. From 1987 to 1990, 300,000 tons of U.S. caustic production was converted from chlor-alkali electrolysis to trona ore purification. Four companies--Tenneco, FMC, Atochem, and Texasgulf--have made major investments in trona facilities. [Hoffman 1990a] PROTECTING WORKERS The large corporations that manufacture chlorine and organochlorines are taking steps to diversify and protect their capital in the face of a likely decline in this industry. No large-scale programs, however, have been established to protect the workers and communities that are dependent on this industry for their livelihoods. Greenpeace believes that the phase-out of chlorine production must include such programs. Workers displaced from this industry need compensation, retraining and new opportunities for higher education. They should be given the time and resources to learn new skills and secure quality jobs without being forced to accept major cuts in income. Communities that depend on these industries also need help to attract new businesses and diversify their economic base. The cost of such programs should be financed by the chlor-alkali industry itself. Labor groups have advocated such an approach, which they call the "Superfund for Workers." It is based on the principle that workers should not be forced to bear the economic burden of the transition to a non-toxic economy: Polluters [should] be held responsible for the entire cost of their negligence, not only of the environment but also of the millions of working people who devote the better part of their lives to making the toxic industries profitable. Modeled on the GI Bill of Rights enacted at the end of World War II, which provided income and tuition support to millions of returning veterans, the Superfund for Workers is proposed as a way of providing similar support to the millions of people who currently are dependent upon the toxic economy for their livelihood. As such, it is more than simply a retraining program for another group of workers who unfortunately find themselves unemployed. [Merrill 1991] For example, a government-imposed $100 per ton surcharge on chlorine production would generate about $1.2 billion per year in the U.S. and $110 million per year in Canada, based on current production rates. If chlorine were phased out over a ten year period, for example, this surcharge would generate a fund of $6 billion in the U.S. and $550 million in Canada. Greenpeace supports the Superfund for Workers approach. The phase-out of the chlorine industry offers a prime and necessary opportunity for implementation of a meaningful, industry- financed worker protection program. REFERENCES (omitted here)