PCBs , contaminants from

The partitioning exhibited through the Henry s Law constant can be used to estimate the vaporization of various PCB contaminants from solid surfaces. In the presence of water, organic compounds volatilize more rapidly than would be expected based upon vaporization of the pure compound. This tendency accounts for the presence of low vapor pressure contaminants, such as the PCBs, in the atmosphere at higher concentrations than one would estimate from the chemistry of the pure compounds [403,408,409]... 

Contaminants migrate from surfaces via diffusion. This effect plays a role in the migration of PCB contaminants from and through soil particles. The less soluble a substance is in a liquid or air, the slower its absolute rate of diffusion into previously pure liquid or air [414]. 

It has been mentioned above that a vapor cleaning system has been proven successful in removing surface PCB contamination from areas previously considered inaccessable. Tbe method has tbe advantage that a minimum quantity of PCB contaminated fluid is derived for disposal in contrast to tbe drain and flush method wbicb produces several times tbe volume of tbe transformer tank. Also, as tbe level of PCB contamination in tbe mineral oil increases tbe vapor cleaning method becomes increasingly necessary and eventually becomes tbe only viable cost-effective procedure. 

Supercritical CO2 has also beea tested as a solveat for the removal of organic contaminants from sod. At 60°C and 41.4 MPa (6,000 psi), more than 95% of contaminants, such as diesel fuel and polychlotinated biphenyls (PCBs), may be removed from sod samples (77). Supercritical CO2 can also extract from sod the foUowiag hydrocarbons, polyaromatic hydrocarbons, chlotinated hydrocarbons, phenols, chlotinated phenols, and many pesticides (qv) and herbicides (qv). Sometimes a cosolvent is required for extracting the more polar contaminants (78). 

The identification of PCB residues in fish, wildlife, and human tissues has been reported since the 1970s (9—13,20—26). The results of these analytical studies led to the ultimate ban on further use and production of these compounds. The precise composition of PCB extracts from biota samples is highly variable and depends, in part, on the specific analyte and the commercial PCB preparations associated with a contaminated area (14). PCBs found in a composite human milk sample from Michigan (26) were highly complex, and the congener composition and their relative concentrations did not resemble any of the commercial PCB preparations. This fact raises obvious problems with regard to the ha2ard assessment of PCB mixtures (27). 

Corrective Action Application At a Navy facility in Guam, approximately 25 tons of PCB contaminated soil was treated using the KPEG (potassium polyethylene glycol) process. PCB concentrations were reduced from 3000 ppm to less than 5 ppm. Upon completion of treatment using the KPEG process, the soil was neutralized from a pH of 14 to 7. A full-scale system for this process is currently under development. 

Leoni [366] observed that in the extraction preconcentration of organochlo-rine insecticides and PCB s from surface and coastal waters in the presence of other pollutants such as oil, surface active substances, etc., the results obtained with an absorption column of Tenax-Celite are equivalent to those obtained with the continuous liquid-liquid extraction technique. For non-saline waters that contain solids in suspension that absorb pesticides, it may be necessary to filter the water before extraction with Tenax and then to extract the suspended solids separately. Analyses of river and estuarine sea waters, filtered before extraction, showed the effectiveness of Tenax, and the extracts obtained for pesticide analysis prove to be much less contaminated by interfering substances than corresponding extracts obtained by the liquid-liquid technique. Leoni et al. [365] showed that for the extraction of organic micro pollutants such as pesticides and aromatic polycyclic hydrocarbons from waters, the recoveries of these substances from unpolluted waters (mineral and potable waters) when added at the level of 1 xg/l averaged 90%. 

Relatively little contamination from PCBs was found in sediments from riverine and pothole wetlands at national wildlife refuges and waterfowl production areas (WPA) in the north central United States in 1980 to 1982. PCBs were above detection levels (20 pg/kg) in less than 4% of the sediments a similar case was recorded in fish from WPAs (Martin and Hartman 1985). Maximum total PCB concentrations in field collections of nonbiological materials were 0.000028 pg/kg in ice, 0.000125 pg/kg in snow, 12.3 pg/m3 in air, 233 pg/L in seawater, 3860 pg/L in sediment interstitial waters, and 1800 mg/kg in sediments. Concentrations were comparatively elevated in urban areas, near anthropogenic activities, and at known sites of PCB contamination (Table 24.8). 

The upper Hudson River was massively contaminated with PCBs from an industrial plant for several decades prior to 1975. All fishing in this section in 1976 was banned because of PCB contamination. The prohibition is still in effect because, in part, of measurable PCB residues in caged fishes from this area (Table 24.9) (Jones et al. 1989). Striped bass (Morone saxatilis) collected near Troy and Albany, New York, contained higher concentrations in muscle of PCB 77 (37 pg/kg FW) and PCB 126 (8 pg/kg FW) than conspecifics from other locations in New York (Hong et al. 1992). Almost all (99%) the PCB toxicity in muscle of striped bass was attributed to PCBs 77, 105 (62 pg/kg FW), and 126 (Hong et al. 1992). 

Adults collected from 4 sites in PCB-contaminated New Bedford Harbor, Massachusetts, in 1993, during their natural spawning season. Transported to laboratory and bred... 

Fed PCB-contaminated common carp (Cyprinus carpio) from Saginaw Bay, Lake Huron. Total PCBs in diet was 8.4 mg/kg FW ration (including, in pg/kg FW, 0.3 of PCB 81,... 

Restum, J.C., S.J. Bursian, J.P. Giesy, J.A. Render, W.G. Helferich, E.B. Shipp, D.A. Verbrugge, and R.J. Aulerich. 1998. Multigenerational study of the effects of consumption of PCB-contaminated carp from Saginaw Bay, Lake Huron, on mink. 1. Effects on mink reproduction, kit growth and survival, and selected biological parameters. Jour. Toxicol. Environ. Health 54A 343-375. 

Fig. 5.4 Representative analyses of environmental samples of GC/NICI-MS-MID PCB contaminated soil from Fountain City, Wl... 

Polychlorinated biphenyls (PCBs) have been used in various industrial processes during the past 40 years but were not recognized as major environmental contaminants until 1966 (1). Fish as a major food source have attained the dubious honor of being the most frequently cited PCB contamination problem (2). In the following presentation disposition of PCBs in fish will be discussed from four points of view accumulation, metabolism, distribution and elimination. No attempt will be made to cover PCB residue levels found in fish in nature (3) or acute or chronic toxicity of PCBs in fish (4-20). 

The salient features of the GC-MS data for the neutral extract components separated from PCB contaminated sediment in New Bedford harbor, Massachusetts are given in Fig. 16. The TIC trace indicates a major UCM with super-... 

Vaporization of the PCB isomers from pure contaminant plated onto a surface generally is dependent upon the degree of chlorination. Figure 9 shows the effect of chlorination on the rate of PCB volatilization from pure isomer and from dry sand (data were taken from [359,417-419]). 

Polychlorinated biphenyls (PCBs) were manufactured by catalytic chlorination of biphenyl to produce complex mixtures, each containing 60-90 different PCB molecular species or congeners (see Chaps. 1 and 4). In the United States, PCB mixtures were manufactured by Monsanto under the trade name Aroclor and were widely used as dielectric fluids in capacitors and transformers from 1929 to 1978. PCBs are widespread contaminants of aquatic sediments and continue to be a focus of environmental concern because they tend to accumulate in biota and are potentially toxic. The following sections show the most effective bioremediation techniques applied to various PCB contaminated environments ... 

In contrast, Williams and May [151] investigated the low-temperature (e.g., 4 °C) microbial aerobic PCB degradation of PCB-contaminated upper Hudson River sediments. They reported the depletion of specific di- and trichloro-biphenyls in the surface layer of PCB-contaminated sediments. The loss of specific PCB congeners from the sediment was indicative of microbial aerobic PCB degradation and demonstrated that this degradation can occur in sediment samples at low temperatures. 

PCB contamination has been observed in the toothed whales iOdontocett) that consume fish, seabird, and other marine mammals. Sperm whales (Physeter macrocephalus, which feed on deepwater squid, have intermediate loads, whereas the predatory dolphins, which feed closer to the surface, carry higher loads. The highest loads have been observed in killer whales (Orcinus orca ), whose diets consists of salmon and seal. In contrast, the baleen whales (Mysttcett) carry much lower loads as their diet is composed of zooplankton. Even whales living in the middle of the ocean fer from land have detectable levels of PCBs and DDT. 

Trstenjak and Perdih (1999) reported that the fungus Phanerochaete chrysosporium removed the majority of PCB-1242 from a saturated water solution at room temperature up to a volumetric ratio of one to several thousand. In static column tests containing pelletized Phanerochaete chrysosporium, the percentage of PCB-1242 not removed ranged from 2.4 to 12% at pellets to contaminated water ratios of 1 5,000 and 1 500,000, respectively. 

Address environmental concerns (runoff, verification sampling for contamination from toxic and hazardous materials such as asbestos, PCBs and other possible hazards)... 

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