Assessment of PCDDs (Polychlorinated Dibenzodioxins) and PCDFs (Polychlorinated Dibenzofurans) from PCB (Polychlorinated Biphenyl's) Transformer and Capacitor Fires

摘要

The EPA, under the Toxic Substances Control Act, has been mandated to develop appropriate regulations for the control of exposure to polychlorinated biphenyls (PCBs). In light of this responsibility the EPA Office of Toxic Substances recently issued an Advance Notice of Proposed Rulemaking (ANPR) intended to define the problem of releases of PCBs and other toxic compounds during fires involving transformers and capacitors containing PCBs. The EPA Office of Research and Development (ORD) has also been mandated under the recently released Dioxin Strategy document to evaluate fire accidents involving PCB transformers and capacitors as potential new sources of polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in the environment. To develop the information to support the two mandated programs, the EPA/ORD undertook this study to assess the problems associated with fires involving askarels, to catalog the contamination experiences and to review potential decontamination methods as well as disposal of contaminated material. This study assesses the chemistry of PCBs under thermal conditions and evaluates the generation of PCDDs and PCDFs. It reviews technologies for destruction and disposal of PCBs and their toxic contaminants. Methodologies to assess potential hazards and reduce exposure are also discussed.