Dioxin is one of the most studied chemicals on the planet. It is found throughout the environment and in our food supply. It causes a wide range of adverse health effects including cancer, birth defects, diabetes, learning and developmental delays, endometriosis, and immune system abnormalities. It is the most potent animal carcinogen ever tested. 

•  What is dioxin and how is it created?
•  Do we know dioxins are in our bodies?  How does they get there?
•  How does dioxins affect our health?
•  How is the government regulating dioxins?
•  Who is working to eliminate dioxins, and how can I help? 
 
 Q: What is dioxin and how is it created? 

A: Dioxin is a family of chemicals containing carbon, hydrogen and chlorine. There are seventy-five different forms of dioxin, with the most toxic being 2,3,7,8-tetrachlorodibenzo-p-dioxin or TCDD. TCDD is more commonly recognized as the toxic contaminant found in Agent Orange and at Love Canal, N.Y. and Times Beach, Missouri.  Dioxin is not deliberately manufactured. Rather, it is the unintended by-product of industrial processes that use or burn chlorine in the presence of organic materials. According to the U.S. EPA, the top three sources of dioxin are municipal waste and hospital incinerators and backyard burn barrels. Additional sources include chemical processing facilities that use chlorine to make products such as polyvinyl chloride (PVC) plastic and pesticides and pulp mills that use chlorine to bleach wood pulp to make paper white.  

Q: Do we know dioxins are in our bodies? How do they get there? 

A: According to the U.S. Environmental Protection Agency the average level of dioxin found in the general U.S. population is at or near the level that can be linked to adverse health effects observed in both animals and people. The EPA interprets this to mean that there is little or no "margin of exposure," meaning that we are nearly "full" and that any additional exposure of dioxin can result in adverse health effects. Some people already have body burden levels that are above average and they may already be suffering adverse health effects. 

The U.S. EPA has determined that 90% of the dioxin that average Americans are exposed to comes from the food we regularly eat, such as meat, dairy, and fish products. Dairy cows and cattle absorb dioxin by eating grass or feed that has become contaminated by airborne dioxins that settled onto soil and plants. The animals absorb and accumulate dioxin in their bodies, which we consume and accumulate in our bodies when we eat food high in fat content such as meat, fish and dairy products.  

Airborne dioxins can be carried long distances downwind from their sources. Studies have shown that people in the arctic region of the world have some of the highest levels of dioxin and other persistent pollutants in their bodies even though they are hundreds of miles from any major source. Eventually, airborne dioxins settle on the earth where they become a major contaminant of our food supply. Dioxins that are discharged into or settle on waterways sink to the bottom and become buried in sediment.  

Q: How do dioxins affect our health? 

A: Exposure to dioxin can lead to a wide array of adverse health effects including cancer, birth defects, diabetes, learning and developmental delays, endometriosis, and immune system abnormalities. 

Dioxin is a known carcinogen. IARC, the International Agency for Research on Cancer, which is part of the World Health Organization, classified it as a known human carcinogen in 1997. In January 2001, the Department of Health and Human Services' National Toxicology Program classified dioxin as a known human carcinogen. The September 2000 draft of the U.S. EPA's Health Assessment document on dioxin also classifies dioxin as a known human carcinogen. In that same report, the U.S. EPA projected an excess cancer risk of one in 100 for the most sensitive people who consume a diet high in animal fats. In other words, the risk of getting cancer from dioxin--over and above the risk of cancer from other sources—is one in 100 for some people. This is a worst-case scenario. It's for the most sensitive people among the five percent of the population who consume the most dioxin. For the average person, EPA estimates a risk level of one in 1,000, which is also a serious risk level. The EPA’s generally "acceptable" risk level is one-in-one-million.

Dioxin also causes a wide range of non-cancer effects including reproductive, developmental, immunological, and endocrine effects in both animals and humans. Animal studies show that dioxin exposure is associated with endometriosis, decreased fertility, inability to carry pregnancies to term, lowered testosterone levels, decreased sperm counts, birth defects, and learning disabilities. In children, dioxin exposure has been associated with IQ deficits, delays in psychomotor and neurodevelopment, and altered behavior including hyperactivity. Studies in workers have found lowered testosterone levels, decreased testes size, and birth defects in offspring of Vietnam veterans exposed to Agent Orange.

Effects on the immune system appear to be among the most sensitive endpoints studied. Animal studies show that dioxin decreased immune response and increased susceptibility to infectious disease. In human studies, dioxin was associated with immune system depression and alterations in immune status leading to increased infections. Dioxin can also disrupt the normal function of hormones—chemical messengers that the body uses for growth and regulation. Dioxin interferes with thyroid levels in infants and adults, alters glucose tolerance, and has been linked to diabetes. 

Q: How is the government regulating dioxins?

A: Despite the alarming information about the dangers of dioxin, the Chlorine Chemistry Council has launched an attack to gut any efforts to eliminate dioxin or adopt a precautionary approach.  One of the chemical industry's prime targets has been the U.S. EPA's “Exposure and Human Health Reassessment of 2,3,7,8-Tetrachlorodibenzo-p-Dioxin (TCDD) and Related Compounds,” which identifies the sources and describes the adverse health effects of dioxin exposure. The U.S. EPA has been researching this report for the last twenty years. The agency released their final draft in 2000, and the final report was expected to be released in 2001. Unfortunately, the EPA has continued to miss their own deadlines and stall its release. Once this report is released the agency will begin to develop comprehensive policies to limit the amount of dioxin released into our environment. The chemical industry does not want this report (commonly known as the Dioxin Reassessment) released for fear it will implicate them in a major public health crisis. 

The U.S. EPA has established some criteria for controlling the amount of dioxin that is emitted into the air with their Maximum Achievable Control or MACT Standards.  They have finalized standards for two of the primary sources of dioxin, medical waste incinerators and municipal solid waste incinerators.  The real success, however, in reducing the amount of dioxin released into our environment comes from closing down and blocking existing medical and municipal waste incinerators through community based efforts nationwide.  Additionally, grassroots activists have fought and won, in many communities, programs to separate and reduce the amount of waste that contains chlorine, such as PVC plastic and advocated for alternatives technologies to dispose of the waste.  It is important that we continue this trend by eliminating industrial releases of dioxin, not just regulating and controlling releases.

In addition, the Stockholm Convention on Persistent Organic Pollutants is an international treaty aimed at eliminating a dozen harmful chemicals including dioxins and furans. The convention was signed in May 2001 and will be valid after it is ratified by 50 countries. While the Bush Administration signed the Stockholm Convention in May 2001, the U.S. has not yet ratified the treaty.  

Q: Who is working to eliminate dioxins, and how can I help? 

A: The Center for Health, Environment and Justice (CHEJ) coordinates the Alliance for Safe Alternatives a national campaign to eliminate persistent toxic chemicals such as dioxin. The campaign is made up of over 500 groups, including farmers, environmental justice groups, faith-based groups, public health advocates, Vietnam Veterans, scientists, and community leaders all working to get persistent chemicals out of our air, soil, water and food. Given that the U.S. government is not doing enough on the regulatory front to protect our communities from harmful chemicals, a primary focus of the campaign is to work at the state and local level to enact and enforce policies that will phase out persistent chemicals like dioxin and its sources. Safe alternatives to the production processes and products that generate dioxin exist and are available and would have minimal costs and great benefits for public health. Campaign partners are also working to shut down, block or clean up the industrial sources of these harmful chemicals.  

To learn more about the health effects of dioxin, the national campaign and what you can do to get involved contact CHEJ at 703-237-2249 or dioxin@chej.org or visit the web site – http://www.chej.org/. 

Prepared by the Center for Health, Environment and Justice
PO Box 6806, Falls Church, VA 22040
703-237-2249, dioxin@chej.org, www.chej.org