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This pamphlet provides answers to basic questions about dioxins. It will explain what dioxins are, where they can be found, how they can affect your health, and what you can do to prevent or reduce exposure to them.


Dioxins are a group of chemicals formed during the burning of household and industrial waste. They also are formed during the making of some herbicides and germicides, and the bleaching of paper pulp. Dioxins also can be found as contaminants in polychlorinated biphenyl (PCB) mixtures. Dioxins were an unwanted by-product of the manufacture of PCBs, which was outlawed in 1978. PCB mixtures are commonly found in electrical capacitors, fluorescent light ballasts and transformers made before 1978. The burning of PCBs can produce dioxins. The use of products containing dioxins has been greatly reduced in the last few decades.


The burning of industrial or household waste can produce dioxins and release them into the air. Soils near burn areas also may be contaminated with dioxins. When PCBs were still in use, dioxins found their way into some bodies of water. Rainwater carried herbicides containing dioxins from farm fields into surface waters, and some factories discharged dioxin-contaminated waste directly into surface water. In lakes, rivers, streams and ponds, dioxins tend to settle to the bottom and cling to solid materials such as mud or clay (sediment).

Since, dioxins last a very long time in the environment before breaking down, they may eventually find their way into the food chain. Dioxins are easily absorbed by the body and are stored in fatty tissue. For this reason, dioxins are slowly eliminated from the body.


Dioxins can enter the body by eating or drinking contaminated food, through the air we breathe or by skin contact. Most people are exposed to dioxins by eating contaminated fish, meats and dairy products. Because freshwater fish (such as catfish, buffalo or carp) may ingest sediments containing dioxins and retain the dioxin in their body fat, they tend to have the highest dioxin levels. Only small amounts of dioxins are taken up by plants from the soil, so amounts in grazing animals and dairy products are generally lower than in fish. Dust contaminated with dioxins may be found on the outer surfaces of fruits and vegetables.

Dioxins do not readily dissolve in water, so exposure to them from contaminated water is not of concern. People are generally not exposed to dioxins in surface waters unless they contact contaminated sediments. The extremely small levels of dioxins in bleached paper products, such as disposable diapers, facial or toilet tissue, and paper towels, are not considered dangerous to people.

Some workers may be exposed to dioxins during the manufacture of some herbicides, germicides or solvents. Waste incinerator workers and persons who burn household waste may come in contact with dioxins in ash, soil, gases or smoke. Industrial accidents have been responsible for most cases of dioxin poisoning in humans. Firefighters and cleanup crews responding to electrical system fires, as well as hazardous waste accidents, also may be exposed to dioxins.


Dioxins are extremely toxic to some animal species, but are much less toxic to others. The toxicity of dioxins to humans is uncertain. In people, dioxins can cause chloracne -- small, pale, yellow skin lesions that may last from weeks to years. Dioxins also can cause short-term changes in the activity of the liver, but without any visible symptoms. These liver changes are similar to those resulting from the consumption of alcoholic beverages.

While dioxins can cause nerve damage in animals, studies have not shown that dioxins cause nerve damage in humans. Birth defects, increased spontaneous abortions and damage to the immune

system have been observed in animals, but these effects have not been seen in people exposed to dioxins.

Large amounts of dioxins given over a short period of time can cause cancer in certain animals. In light of this, the United States Environmental Protection Agency has classified dioxins as probable human carcinogens (cancer-causing chemicals). However, there is no evidence that dioxins cause cancer at the low levels normally found in the environment. Since dioxins occur as impurities in other chemicals, it is difficult to determine whether dioxins actually cause any adverse health effects. Adverse health effects may result from the chemicals that contain dioxins and not from the dioxins themselves.


Exposure to dioxins can be minimized by following the Guide to Eating Illinois Sport Fish, available from the Illinois Environmental Protection Agency. Copies are available by calling 217- 782-3362. This guide tells what fish you should eat and how to prepare the fish for eating. Because dioxins accumulate in fish fat, people can reduce their intake of dioxins by removing the skin and fatty areas from fish filets. Do not fry fish. Barbecue, broil, or bake fish on an elevated rack that allows fat to drip away. Throw away the drippings. You can also poach fish as long as you throw away the broth.

Other ways to avoid exposure to dioxins include washing fruits and vegetables before eating and not breathing smoke and vapors given off by burning household waste.


Illinois Department of Public Health
Division of Environmental Health
525 W. Jefferson St.
Springfield, IL 62761
TTY (hearing impaired use only) 800-547-0466

This pamphlet was supported in part by funds from the Comprehensive Environmental Response, Compensation, and Liability Act trust fund through a cooperative agreement with the Agency for Toxic Substances and Disease Registry, Public Health Service, U.S. Department of Health and Human Services.