Acceptable Levels of Dioxin Contamination in an Office Building Following a Transformer Fire

摘要

The report assesses the health effects of dioxin in order to determine acceptable levels of exposures to dioxin in an office building that had a PCB transformer fire. The Committee concluded that short-term exposures to high concentrations of dioxins (especially 2,3,7,8 tetrachlorodibenzodioxin) are associated with chloracne in humans. Studies concerning reproductive effects have not shown adverse effects among progeny of men who were exposed to dioxins. The results of human cancer studies of exposure to dioxins are inconsistent, but in general the studies are of low power and inconclusive exposure assessment. The overall evidence from human studies does not indicate a greatly increased risk of cancer in association with exposures experienced. Studies in animals have shown increased risk of cancer, adverse reproductive effects, and alterations in immune function. Acute effects include body-weight loss, thymic atrophy, neurotoxicity, and liver effects. Various carcinogenic risk assessments were reviewed and the Committee decided that the approach taken by the New York State Health Department was most appropriate and adopted its exposure guidelines, i.e., 10 pg/cu m for air and 25 ng/sq m for surfaces.