World Awash in Chlorine Based Poisons
By Cat Lazaroff
WASHINGTON, DC, June 8, 2000 (ENS) - Agent Orange, DDT, PCBs - they are famous chemicals, notoriously toxic - notoriously banned. Yet they, and their legal cousins, continue to contaminate the environment, wildlife, our food and our bodies. A new book details the dangers of these related poisons, and suggests an antidote: ban them all.
Plastic trash bags and many other common plastic products can contain toxic organochlorines (Photo courtesy Universal Plastic)
The banned substances listed above have one important ingredient in common: they all contain chlorine. They are part of a class of chemicals known as organochlorines, formed when chlorine gas produced by the chemical industry comes into contact with organic matter in industrial processes.
There are 11,000 organochlorines produced commercially, and thousands more are formed as byproducts. They share the dangerous properties of persistence and stability in the environment, and accumulation in the fatty tissues of animals and humans.
Although organochlorines have only been produced in large amounts since 1940, they now blanket the entire planet, reaching from the deep oceans to the high Arctic, from the Mississippi River to the Amazon rainforests.
"Everyone on Earth now eats, drinks and breathes a constantly changing and poorly characterized soup of organochlorines, including dozens of compounds that cause severe health damage at low doses," said Joe Thornton, a biologist at Columbia University�s Center for Environmental Research and Conservation.
Thornton has written a new analysis of the global consequences of organochlorines, known as persistent organic pollutants (POPs). "Pandora�s Poison: Chlorine, Health and a New Environmental Strategy" presents a compelling body of evidence suggesting that these chemicals have already begun to cause large scale damage to public health, including increasing cancer rates and impaired child development.
Fires, like this one at a PVC plastics plant in Canada, can release enormous amounts of dioxin and other toxins into the air (Photo courtesy Greenpeace)
Analyses of human fat, mother�s milk, blood, breath, semen and urine demonstrate that everyone - not just those living near major pollution sources - now carries a "body burden" of toxic organochlorines in his or her tissues. At least 190 organochlorines, including dioxins, PCBs and DDT, have been identified in the tissues and fluids of the general population of the U.S. and Canada. Hundreds more are present, but have not been chemically characterized.
Organochlorines have been linked to immune system suppression, falling sperm counts and infertility, as well as learning disabilities in children. More than 100 organochlorines cause cancer in laboratory animals or humans. The U.S. Environmental Protection Agency will officially release a report Friday finding that dioxin - the most toxic of the organochlorines - is a human carcinogen.
These chemicals are present throughout the environment, but particularly in animal tissues. Because they build up in fatty tissues, and are not destroyed by digestive processes, the more you eat, the more you carry. Animals higher up the food chain, such as eagles, wolves and humans, carry the burden of all the organochlorines from the meat they have eaten.
In the Great Lakes region of the U.S., dioxin and related compounds have caused epidemic reproductive, developmental and immune system damage in fish, birds and mammals, "Pandora�s Poison" reports.
Polar bears have some of the highest body burdens of organochlorines of any species (Photo courtesy Greenpeace)
Polar bears, which eat fish, seals and other heavily contaminated animals, carry some of the world�s highest levels of organochlorines in their tissues. "Contamination of polar bear tissues with dioxins and PCBs is so severe, in fact, that the bears� body burdens exceed by a substantial margin the levels that are known to cause reproductive failure, immune suppression and altered brain development in other kinds of mammals," Thornton writes.
Humans are not immune. Dioxin exposure is particularly severe for Arctic peoples, who eat a diet similar to the polar bears�. Dioxin levels in the milk of Inuit mothers are two to 10 times higher than in the rest of the U.S. and Canadian populations
"Organochlorines interfere with the basic machinery � with which the body regulates itself," said Thornton. "They are incompatible with basic physiological functions."
Because organochlorines are so stable in the environment, even banned substances like the pesticide DDT continue to poison the ground and water. Related chemicals, including Dursban, the most widely used pesticide in the U.S., are only now coming under restrictions. The EPA will announce today new limits on the amount of Dursban that can be used on crops and in or around buildings.
Thornton says these piecemeal measures are not enough to counter the larger problem of organochlorines in the environment.
Joe Thornton, author of "Pandora's Poison: Chlorine, Health and a New Environmental Strategy" (Photo courtesy Columbia University)
"Organochlorines can�t be reduced to a handful of bad actor compounds like DDT," he said Wednesday at a press conference marking the release of "Pandora�s Poison." "Virtually all organochlorines tested have one or more toxic effects."
The growing body of evidence on the health and environmental risks posed by these chemicals points to one conclusion, Thornton holds: they are all unsafe. In his book, Thornton argues that regulators and legislators should begin treating organochlorines not as individual substances but as single entity.
"The current effort to regulate individual substances is doomed to fail," writes Thornton. "Of the thousands of organochlorines in production, only a small fraction has been subject to basic toxicity testing, and complete health hazard information is available for none. Developing the information base to predict the health impacts of each chemical would take centuries, and in the meantime, the public is exposed to a cocktail on untested substances."
Current regulations, like the new restrictions on Dursban, attempt to set acceptable discharge levels for individual chemicals, and to control individual sources. This strategy "has failed miserably to prevent global contamination," said Thornton. "Even acceptable discharges build up to unacceptable levels."
Already, the average body burden of dioxin alone in the U.S. is at or near the range where reproductive, developmental and immunological effects occur in laboratory animals. This newly named carcinogen is produced at some point during the lifecycle of all chlorine based chemicals - in the production of chlorine gas, the synthesis of all organochlorines, and the combustion of any organochlorine product or waste.
Huge amounts of plastic waste are produced each year. Disposing of these wastes without releasing organochlorines into the environment may be nearly impossible (Photo David Humber courtesy National Renewable Energy Lab)
The levels of dioxin in the environment can only increase, as long as organochlorines are produced, Thornton warns. "Once we�ve got them, we�ve got them, and there�s no safe way of disposing of them," said Thorton. "Once they�re in you, there�s no way to get them out."
Thornton suggests that governments worldwide plan a "chlorine sunset": a gradual phase out of the major applications of chlorine and organochlorines in favor of safer alternatives.
That means replacing latex medical tubing and PVC pipes with non-chlorine containing plastics; vinyl siding with wood or metal; chlorinated bleach with oxygen based bleaches; organochlorine pesticides with safer versions; and so on, in list of applications that spans nearly every human endeavor.
"Society does not try to address insect infestations by targeting individual bugs or traffic problems by regulating individual cars," writes Thornton. "In these cases, society has decided that it is more effective to focus on the systemic causes of problems rather than their manifestations at [the individual level], which are too numerous and uncontrollable to be micromanaged."
"Pandora�s Poison" lists reasons why a "chlorine sunset" is technologically and economically feasible. "Safer, affordable alternatives are available now for the vast majority of chlorine uses," Thornton said. "With better processes at hand, there can be no excuse - political, economic or ethical - for not making the changes necessary to protect the health of our children and grandchildren from the global hazards of organochlorines."
A substantial proportion of the organochlorines which have accumulated in a woman's body during her whole lifetime are passed to her child during development in the womb and through breast feeding (Photo courtesy Greenpeace)
Within the next month, Thornton and his wife Margie will have their first child, a baby boy. On Wednesday, Thornton talked about his fears that his new son could suffer health problems due to exposure to organochlorines in the womb, and after he is born.
"That baby is awash in industrial chemicals," said Thornton, holding up an ultrasound image of his unborn child. "My wife, Margie, has accumulated hundreds of industrial compounds in her tissues, and these substances have crossed the placenta and entered the baby�s bloodstream. My semen contains scores of pollutants that may have damaged the DNA I contributed to the baby."
"Some of these chemicals are flushed out of the body by breast feeding, so the baby will get even higher doses after he is born," Thornton continued. "No mother should have to worry that doing the most natural, nurturing thing in the world may be putting her child at risk."
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