Polychlorinated biphenyls authorizations

EPA. 1984c. Method T04 for the determination of organochlorine pesticides and polychlorinated biphenyls. In Winberry et al. Compendium of methods for the determination of toxic organic compounds in ambient air. U. S. Environmental Protection Agency, Office of Research and Development, Research Triangle Park, NC. (authors Winberry, et al). EPA-600/4-84-041. 

For many, familiarity with the TSCA generally stems from its specific reference to polychlorinated biphenyls, which raise a vivid, deadly characterization of the harm caused by them. But the TSCA is not a statute that deals with a single chemical or chemical mixture or product. In fact, under the TSCA, the EPA is authorized to institute testing programs for various chemical substances that may enter the enviromnent. Under the TSCA s broad authorization, data on the production and use of various chemical substances and mixtures may be obtained to protect public health and the environment from the effects of harmful chemicals. In actuality, the TSCA supplements the appropriate sections dealing with toxic substances in other federal stamtes, such as the Clean Water Act (Section 307) and the Occupational Safety and Health Act (Section 6). 

During many decades a factory has spilled polychlorinated biphenyls (PCBs) into a small creek which leads to a small lake. Meanwhile the pollution has stopped, yet the local authorities are afraid that PCB concentrations in the outlet of the lake may still be dangerous for the drinking-water supply operating on the aquifer further downstream. You are asked to make a first guess whether this fear may be substantiated. You decide to use a simple box model. Where would you draw the boundaries of the model and which subcompartments (if any) would you choose ... 

Jansen and co-workers [86] have evaluated temperature-controlled outgassing processes of plastics and rubbers using both off-line and on-line TD-GC-FTIR-MS. Decomposition of polyesterurethanes by means of TG-Tenax off-line sampling followed by TD-GC-FTIR-MS revealed C02, H20, tetrahydrofurane, cyclopentanone, dicarbonic acid, aliphatic diols and esters [86]. The same authors have also described the detection of polychlorinated biphenyls (PCB) in 2,4-dichlorobenzoylperoxide cured silicone rubbers after outgassing products of a rubber silicone part obtained after desorption for 10 minutes at 200 °C in the thermal desorption cold-trap and subsequent analysis by means of TD-GC-MS. Using a mass range of 290-294 Da the MS can be used as a selective detector for these substances. 

While industrial practice requires a trial burn and a facility may not operate until the data are accepted, industrial facilities obtain approval to process many different waste streams based on a single trial burn. In special situations, particularly with toxic materials such as polychlorinated biphenyls, both a surrogate burn and a trial burn would be required. RCRA regulations offer the option of allowing the use of data from another facility, under certain conditions, in lieu of a trial burn. However, industry has used this mechanism at only a few sites with similar units. It has been used twice by the CMA for the Tooele, Utah, disposal facility. The CMA should pursue this mechanism with the respective regulatory authorities. The committee believes that chemical agent disposal facilities are treated similarly to industrial facilities with respect to the conduct of trial bums. 

Gobas et al. [30] in 1989 investigated the bioconcentration potential of polychlorinated biphenyls (PCBs), polybrominated benzenes (PBBzs) and poly-brominated biphenyls (PBBs), and other super-hydrophobic chemicals, such as decachlorobiphenyl and Mirex. These authors also pointed out the importance of bioavailability for bio concentration of super-hydrophobic chemicals. Their study showed that the bioavailable fraction of the super-hydrophobic chemical decachlorobiphenyl can be as low as 3 % and of Mirex can be as low as 2.2 %. For decachlorobiphenyl, a BCF was found that was one to two orders of magnitude lower than the true BCF. 

It is very likely that the polybrominated biphenyls are metabohzed in fish, sea mammals, and human to debrominated and hydroxylated polybrominated biphenyls. It is suggested by the authors that some of these polybrominated metabolites can bind to the estrogen receptor and act hke xenoestrogens, as was shown for hydroxy polychlorinated biphenyls (HO-PCBs) by Korach et al. [256], McKinney and Waller [257], and Waller et al. [258]. Especially the chemical structure of para-substituted hydroxylated metabohtes of polybrominated biphenyls would be similar to that of estradiol, preferably in the presence of... 

Narbonne JF, Gillet G, Daubeze M. 1978. [Effect of polychlorinated biphenyls in the rat I. - relation tissue level dose (author s transl)]. Toxicological European Research 1(3) 145-52. 

EPA has authority to require chemical labeling under Section 6 of TSCA. This provision empowers EPA to develop labeling requirements for particular chemicals or chemical classes (Section 6(a)). It also specifically directs EPA to promulgate labeling requirements for polychlorinated biphenyls (PCBs) by prescribed deadlines (Section 6(e)). While EPA has not yet formally exercised its labeling authority except in connection with PCBs, the development of hazard warnings under TSCA for individual chemicals or chemical classes remains a distinct possibility for the future. 

B) The Administrator may by rule authorize the manufacture, processing, distribution in commerce or use (or any combination of such activities) of any polychlorinated biphenyl in a manner other than in a totally enclosed manner if the Administrator finds that such manufacture, processing, distribution in commerce, or use (or combination of such activities) will not present an unreasonable risk of injury to health or the environment. 

This subsection does not limit the authority of the Administrator, under any other provision of this chapter or any other Federal law, to take action respecting any polychlorinated biphenyl. 

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