Polychlorinated biphenyls conditions

Not all of these isomers are completely separated by the conditions given here, but all arc readily detected by plotting the masses of the molecular ions. Pesticides can interfere with polychlorinated biphenyl (PCB) analysis. 

Colenut and Thorburn [51,52] have also described the procedure using gas stripping of the aqueous sample followed by adsorption onto active carbon from which surface they are taken up in an organic solvent for gas chromatographic analysis. They optimized conditions for the determination of parts per billion of pesticides and polychlorinated biphenyls. 

Quensen et al. [69] showed that micro-organisms isolated from Hudson river sediment dechlorinated most polychlorinated biphenyls in Aroclor 1242 under anaerobic conditions in the laboratory. The higher the polychlorobiphenyl concentration, the more rapid the rate of dechlorination. The possible mechanisms involved are discussed. The products of dechlorination were less toxic than the original compounds and were more readily degraded by aerobic bacteria wastewater containing... 

Iwata, Y., Westlake, W.E., and Gunther, F.A. Varying persistence of polychlorinated biphenyls in six California soils under laboratory conditions. Bull Environ. Contam. Toxicol, 9(4) 204-211, 1973. 

Boon, J.R and Duinker, J.C. (1985). Kinetics of polychlorinated biphenyl (PCB) components in juvenile sole Solea solea) in relation to concentrations in water and to hpid metabolism under conditions of starvation. Aquatic Toxicology, 7 119-134. 

At supercritical conditions these solvents effectively extract relatively polar compounds such as polychlorinated biphenyls, dibenzo-p-dioxins, and dibenzofurans without the use of a cosolvent (Roth, 1996). 

In addition to the ability of TGA to quantify the thermal character of soil and sediment organic matter, it has been employed to study the adsorption of volatile organic compounds onto soil and sediment organic matter. For example, Boussehain et al. (1986) used TGA to study alcohol adsorption on charcoals, from which adsorp-tion/desorption isotherms were developed at various temperatures and adsorption models were used to lit experimental data. In addition, Risoul et al. (2002) performed laboratory pilot studies on thermal desorption of polychlorinated biphenyls (PCBs) from a contaminated soil. This study indicated that TGA appears to be a promising tool to determine optimum operating thermal extraction conditions. 

Huisman M, Koopman-Esseboom C, Lanting Cl, et al. 1995b. Neurological condition in 18-month-old children perinatally exposed to polychlorinated biphenyls and dioxins. Early Hum Dev 43 165-176. 

Polychlorinated biphenyls are manufactured by chlorination of biphenyl. The conditions determine the degree of chlorination. 

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. 

More oxidized compounds, such as chlorinated benzenes, are susceptible to biologically mediated reduction in environments under anaerobic conditions, such as in lake and river sediments. It is known that highly polychlorinated biphenyl (PCB) congeners, for example, are susceptible to reductive dehalo-genation, the result of the interaction of syn-trophic microbial communities that are active under methanogenic and sulfate-reducing... 

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