PCDFs are found at very low levels in the environment of industrial countries and at even lower levels in non industrial countries. People are exposed to very small levels of PCDFs by breathing air, drinking water, and eating food, but most human exposure comes from food containing PCDFs. The levels of PCDFs in air are usually higher in city and suburb areas than in rural areas.

PCDFs are not found in soils that have not been polluted. PCDFs have been detected in the stack emissions and ash from certain industries and processes that are sources of these compounds in air at levels that are thousands of times higher than the levels in the air that people usually breathe. Once emitted in the air from stacks, furans are dispersed by the cleaner air and the level of PCDFs drops substantially. Similarly, the concentrations of PCDFs in waste waters from certain industries and in soil at dumpsites can be thousands to millions times higher than the levels found in clean water and soil.

Since PCDFs tend to concentrate in the fat, and milk contains fat, mother’s milk can be a source of PCDFs for babies. But considering the small amounts of PCDFs in milk and the other beneficial effects of human milk to a baby and the length of time a baby uses mother’s milk, scientists believe that mother’s milk, on balance, is still beneficial to babies. Cow’s milk and formula usually contain lower amounts of PCDFs than human milk.

Children playing in dumpsites may come in contact with furans through their skin and by eating dirt. It has been estimated that over 90% of the total daily intake of PCDFs for the general adult population occurs from eating food containing them. The rest comes from air, consumer products, and drinking water. Meat and meat products, fish and fish products, and milk and milk products contribute equally to intake of PCDFs from food, while intake from vegetable products contributes much less. Eating large amounts of fatty fish from water contaminated by PCDFs may increase one’s daily intake from food.

People in certain occupations may be exposed to higher levels of PCDFs than the general population. Exposure in the workplace occurs mostly by breathing air and touching substances that contain PCDFs. Workers involved with cleaning up after transformer fires, workers in the pulp and paper mill industry, workers in municipal incinerators, and workers in sawmills may be exposed to higher levels of furans than the general population. Contact with PCDFs at hazardous waste sites can happen when workers breathe air or touch soil containing PCDFs.

Route of ExposureSymptomsFirst Aid
InhalationChloracne. Symptoms may be delayed.Fresh air rest. Refer for medical attention.
SkinMAY BE ABSORBED! Redness. Pain. (See Inhalation).Remove contaminated clothes. Rinse and then wash skin with water and soap. Refer for medical attention.
EyesRedness. Pain.First rinse with plenty of water for several minutes (remove contact lenses if easily possible) then take to a doctor.
Ingestion(See Inhalation).Give a slurry of activated charcoal in water to drink. Induce vomiting (ONLY IN CONSCIOUS PERSONS!). Refer for medical attention.

Notes for ICSC Information:  This chemical is only produced for research purposes but could be generated as a by-product from chemical processes or fires.


Structure formula of 2,3,7,8-Tetrachlorodibenzo-furan