The U.S. Environmental Protection Agency (EPA) has issued its non-cancer dioxin reassessment 27 years after the ubiquitous chemical was last assessed and has established a consumption limit of 0.7 picogram of dioxin per kilogram of body weight per day. The agency has found that, while low-dose exposures persist, primarily from the consumption of meat, fish and other animal products, and ultra-low levels of exposure can pose health risks, “current exposure to dioxins does not pose a significant health risk” over a lifetime, given significant reductions in industrial dioxin emissions.
According to EPA, air emissions of the chemical from industrial processes have been reduced 90 percent since the 1980s, but it breaks down slowly and remains in the water and soil to be consumed by fish and livestock feeding on contaminated plants. Most ambient dioxin today is apparently a result of backyard trash burning. The non-cancer health effects examined in this part of the dioxin reassessment, purportedly the result of large exposures from accidents or significant contamination events, are chloracne, “developmental and reproductive effects, damage to the immune system, interference with hormones, skin rashes, skin discoloration, excessive body hair, and possibly mild liver damage.” EPA intends to release a cancer reassessment at a later date.
Environmental activists reportedly lauded the reassessment, but questioned EPA’s minimal risk conclusion because some people have higher exposures or are more vulnerable to potential health effects than others. According to one scientist, fetuses, nursing babies and those with suppressed immune systems, such as AIDS patients and transplant recipients, are more sensitive to dioxin exposure. Industry interests called the draft reassessment on which the document is based “scientifically flawed” and claimed that EPA overstated the risks because exposures are now exceptionally low. See EPA News Release and Environmental Health News, February 17, 2012.