Technical Polychlorinated Biphenyls Research Articles

Enhanced accumulation of PCB congeners by baltic sea blue mussels,Mytilus edulis, with increased algae enrichment

The objective of this study was to examine if natural variations in the quantity of phytoplankton-derived particulate and dissolved organic carbon influences the accumulation of polychlorinated biphenyls (PCBs) in the tissues of Baltic Sea blue mussels (Mytilus edulis L.). In a laboratory flow-through experiment we exposed M. edulis to the technical PCB mixture Aroclor® 1248 for 21 d at three different enrichments of the unicellular green algae Chlamydomonas sp., 0.10, 0.16, and 0.32 mg particulate organic carbon (POC)/L. Tissue and water concentrations were determined for seven PCB congeners (International Union of Pure and Applied Chemistry [IUPAC] 52, 101, 105, 118, 138, 153, and 180), and 21-d bioaccumulation factors were calculated against total water concentrations. Contrary to what would be expected, an increase in algae enrichment from 0.10 to 0.32 mg POC/L resulted in an enhanced PCB accumulation by a factor of approx. 2. This increase in PCB accumulation was more pronounced for PCB congeners with lower hydrophobicity. These observations have implications for the design of laboratory accumulation studies and potentially for PCB accumulation and cycling in field populations of suspension-feeding mussels in response to changes in eutrophication status.

Persistent Organochlorine Residues in Air, Water, Sediments, and Soils from the Lake Baikal Region, Russia

Contamination of semivolatile organochlorines (OCs) such as hexachlorobenzene (HCB), hexachlorocyclohexanes (HCHs), DDTs, chlordanes, and polychlorinated biphenyls (PCBs) was assessed in air, water, sediments, and soils from the Lake Baikal region, Russia. Comparison of the residue levels in the lake with those in other regions suggested the presence of local sources of DDTs and PCBs, although the residues were considered to be lower than those in the low-latitude areas in the eastern Asia and Oceania. Larger proportions of p,p'-DDT to total DDTs and similarities of PCB congener compositions to a Russian technical PCB formation were found in the samples analyzed, implying their usages nearby the lake. The estimated fluxes of OCs by gas exchange across the air-water interface applying the two-film model indicated that the lake water plays a role as a sink for HCB, HCHs, and DDTs and also serves as a source for PCBs. The magnitude for PCB volatilization in this lake was found to be smaller than those in the Great Lakes for which the values have been previously reported.

HRGC Separations of 160 Chlorobiphenyls in Technical Mixtures on Four Polar Narrow-Bore Columns

Abstract The separation of 160 chlorobiphenyl (CB) congeners from technical polychlorinated biphenyl (PCB) mixtures was investigated on four narrow-bore, fused silica gas chromatography (GC) columns with high temperature resistant polar stationary phases: 15% diphenyldimethylsiloxane (0.20 μm SIL-13,50m×0.25 mm), 50% diphenyl dimethylsiloxane (0.25; gmm DB-17, 60 m×0.25 mm), a series combination of 5% diphenyldimethylsiloxane (0.25 μm SIL-8,25 m×0.25 mm) with 1,10-dicarba-closo-dodecarborane dimethylsiloxane (0.1 μm HT-5. 25 m×0.2 mm) and a 70% cyanopropyl silphenylene dimethylsiloxane copolymer0(0.25 μm BPX-70,50 m×0.22mm). Technical PCB mixtures (Aroclors) and authentic standards (totally 149 CBs) were injected on the narrow-bore columns and analyzed by GC-ECD and GC-MS. Structural principles for retention of CBs and the retention mechanism of diphenyl and cyanopropyl in the stationary phase are discussed. SIL-13 proved to be an interesting alternative to the widely used SE-54 type columns. DB-17 showed...

Improved congener‐specific GC analysis of chlorobiphenyls on coupled CPSil‐8 and HT‐5 columns

AbstractThe congener‐specific analysis of polychlorinated biphenyls (PCB) by high resolution gas chromatography on a 50 m × 0.25 mm fused silica column coated with a 0.26 μm film of 5% diphenyl polydimethylsiloxane (CPSil‐8) has been significantly improved by series coupling with a 25 m × 0.22 mm column coated with a 0.10 μm film of 1,2‐dicarba‐closo‐dodecarborane polydimethylsiloxane (HT‐5). Using helium as carrier gas, a total of 64 congeners in technical PCB mixtures could be analyzed as resolved peaks by ECD (86 by MS) with the CPSil‐8 column, and 84 by ECD (108 by MS) with the combination. The high upper temperature limit for these stationary phases (>300°C) enabled fast temperature programming and rapid analysis (60 min).

Separation of Toxic Congeners from PCB Mixtures on Two Series Coupled Narrow-Bore Columns (50 m SIL-8 AND 25 m HT-5)

Abstract The complete separation of the toxic non-ortho-substituted polychlorinated biphenyls (PCBs) PCB-77, PCB-126 and PCB-169 from the technical PCB mixtures Askarel and Aroclors (A1232, A1242, A1248, A1254, A1260 and A1262) was obtained on two series coupled narrow-bore columns: 50 m × 0.25 mm, 0.26 μm 5% diphenyldimethylsiloxane (CP-SIL-8) and 25 m × 0.2 mm, 0.1 μm 5% 1,2-dicarba-closo-dodecarborane dimethylsiloxane (HT-5). The high upper temperature limit for these GC-phases (>300°C) allowed for fast temperature programming and short analysis time (60 min). In addition to the non-ortho-substituted PCBs most of the toxic mono-ortho-substituted PCBs were completely separated from other PCBs (PCB-74, PCB-81, PCB-105, PCB-118, PCB-123, PCB-157 and PCB-189). Only four toxic PCBs were eluted with interference: PCB-60/PCB-56, PCB-114/PCB-134, PCB-167/PCB-128 and PCB-156/PCB-202. These could be analyzed satisfactorily on a CP-SIL-19 column i.e. 50 m × 0.25 mm, 0.20 μm 14% cyanopropylphenyl 1% vinyldimethyls...

Congener Specific Analysis of 140 Chlorobiphenyls in Technical Mixtures on Five Narrow-Bore GC Columns

Abstract The separation of 140 chlorobiphenyl (CB) congeners from technical polychlorinated biphenyl (PCB) mixtures was investigated on five narrow-bore (0.22–0.25 mm I.D.) gas chromatography (GC) columns with stationary phases representing a broad range of polarities: dimethylsiloxane (0.15 μm SIL-5, 50 m), 5% diphenyl dimethylsiloxane (0.26 μm SIL-8, 50 m), 14% cyanopropylphenyl 1% vinyl dimethylsiloxane (0.26 μm SIL-19, 50 m), bis-cyanopropyl phenylsiloxane (0.20 μm SIL-88, 50 m) and 1,2-dicarba-closo-dodecarborane dimethylsiloxane (0.1 μm HT-5, 25 m). Technical PCB mixtures (Aroclors) and authentic standards (totally 66 CBs) were injected on the narrow-bore columns and analyzed by GC-ECD and GC-MS. Peak assignments were based on experimental data together with published retention data and data on the quantitative composition of Aroclors. Structural principles for retention of CBs on polar stationary GC phases were developed. Surprisingly, the general performance of the classical column for PCB analysi...

Effects of a Technical PCB Preparation and Fractions Thereof on Ethoxyresorufin O‐Deethylase Activity, Vitamin A Levels and Thymic Development in the Mink (Mustela vison)*

Clophen A50, a technical preparation of polychlorinated biphenyls (PCBs), was separated into four fractions; three containing chlorobiphenyls with 0, 1, or 2 to 4 ortho chlorines and one containing di- and tricyclic impurities such as naphthalenes and dibenzofurans. Clophen A50, the four fractions, and a synthetic mixture of the biologically most active non-ortho-chlorinated congeners (3,3',4,4'-tetra-, 3,3',4,4',5-penta-, and 3,3',4,4',5,5'-hexachlorobiphenyl), were separately mixed in the feed and given to female mink during the reproductive season. The concentration of a given compound in the feed mixture was equivalent to its concentration in the feed mixed with Clophen A50. Hepatic 7-ethoxyresorufin O-deethylase (EROD) activity in adults was enhanced 2-3 times by Clophen A50, the fractions containing non- or mono-ortho-chlorinated congeners, and the synthetic mixture. In neonatal kits delivered by females treated with non- or mono-ortho-chlorinated congeners, EROD was enhanced to about 30 times the control value. No live kits were delivered by the females treated with unfractionated Clophen A50. The fractions containing congeners with two to four ortho chlorines or di- and tricyclic compounds did not significantly induce EROD in either adults or kits. Clophen A50 reduced hepatic and pulmonary vitamin A contents in adult mink, while renal vitamin A was unaffected. Responses to the fractions containing the non- and mono-ortho-chlorinated congeners were similar to those obtained with Clophen A50. Their effects were, however, less pronounced, particularly with respect to the hepatic vitamin A reduction. The fractions containing congeners with two to four ortho chlorines and the di- and tricyclic compounds had no significant effects on tissue vitamin A contents.(ABSTRACT TRUNCATED AT 250 WORDS)

Supercritical fluid chromatographic separation of polychlorinated biphenyls (PCBs) using a negative temperature gradient for density programming

AbstractThe technical PCB mixtures Aroclol and Clophen have been analyzed by packed column supercritical fluid chromatography using negative temperature programming. The chromatographic method was successfully applied to the analysis of PCBs, polycyclic aromatic hydrocarbons, and polychlorinated dibenzo‐p‐dioxins in extracts from environmental matrices.

Toxicity and erod-inducing potency of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in avian embryos

1. 1. The toxicities of various polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) were studied in chick embryos ( Gallus domesticus). The substances were injected into the yolks of eggs preincubated for 4 days and mortality was measured 2 weeks later. A technical PCB preparation caused 33% embryo mortality at a dose of 5 mg kg egg and 2 mg kg of a mixture of 18 PAHs caused 40% mortality. 2. 2. 3,3′,4,4′,5-Pentachlorobiphenyl, a coplanar PCB, was the most toxic (90% mortality at 2 μg kg ) of 11 PCBs and 18 PAHs tested in chick embryos using the 2-week test. Benzo[ K]fluoranthene, which was the most potent of the PAHs, was about 1000 times less toxic than 3,3′,4,4′,5-pentachlorobiphenyl in this test. 3. 3. Several avian species were studied in a similar test and they all proved to be considerably less sensitive than the chicken to the embryotoxicity of coplanar PCBs. Embryos from the turkey ( Meleagris gallopavo), domestic duck ( Anas platyrhynchos) and eider ( Somateria mollissima) were, however, at least as sensitive as chick embryos to the PAH mixture and to benzo[ k]fluoranthene. 4. 4. The most toxic compounds tested were also the strongest inducers of hepatic 7-ethoxyresonifin O-deethylase (EROD) activity in 10-day-old chick embryos. 3,3′,4,4′,5-Pentachlorobiphenyl, which was the most potent of the tested PCBs, had an ed 50 of 0.1 μg kg whereas the ed 50 for the nonplanar 2,2′,4,4′,5,5′-hexachlorobiphenyl was > 40,000 μg kg .

Polychlorierte Biphenyle (PCB) in Fischen aus Teichwirtschaften und Nachkl�rteichen

The concentrations of six selected single polychlorinated biphenyl (PCB) congeners, for which legal tolerance levels became valid in 1988, and the congener no. 49 (2,2',4,5'-tetrachlorobiphenyl) were determined in the muscle tissue of 58 fishes from fish hatcheries and in 17 fishes from settle ponds. The fish were taken from flowing waters in the years 1986 and 1987. High and low chlorinated biphenyls were present in each sample, but the concentration of the low chlorinated biphenyls was distinctly lower than that of the higher chlorinated ones. Nevertheless these results demonstrate the intake of components of low chlorinated technical PCB mixtures in the environment and food chains. Compared with the investigations carried out in 1980/81 in fishes from fish hatcheries, a decrease of PCB contamination in the muscle tissues with regard to the technical mixture Clophen A 60 was observed. This is in accordance with the results our team obtained a short time previously in muscle tissue from foxes and in food-stuffs. The concentration of all PCB congeners determined in the muscle tissue from fish of settle ponds was significantly higher than in the tissue from fish taken from hatcheries. Thus, the PCB content depends on the PCB load in different environments. Therefore, fishes can be useful as bioindicators for the intake of low and high chlorinated PCB congeners in aquatic ecosystems.

Polychlorierte Biphenyle: Bestimmung der Einzelkomponenten in Rohmilch und kontaminierten Futtermitteln

Since 1980, 2145 samples of raw milk from producers in the district of Freiburg have been analysed for polychlorinated biphenyls (PCB) during a monitoring programme. In 1983, we started to search for the source of PCB, whenever milk was contaminated above the average value (above 0.2 mg/kg fat, calculated as Clophen A60). In 7 cases, previous coats of paint in the silos proved to be the cause of the PCB contamination. Five samples of milk and 4 corresponding silages as well as 1 sample of wood (from a cowshed) were investigated for all of the individual PCB components included in the technical mixtures of Clophen A30 and A60. Two samples of silages contained both low and high chlorinated biphenyls, whereas low chlorinated biphenyls (di-, tri-, and tetrachlorinated biphenyls) were not detected in the corresponding milk samples. Pentachlorinated biphenyls were only detected in the range of 1%-2%. In the samples of wood and corresponding milk, a different PCB pattern appeared. There were remarkably high percentages of hepta- and octachlorinated biphenyls as well as a lower percentage of hexachlorinated biphenyls. The exact PCB content of the milk, determined by the addition of all single components, proved to be approximately half the value obtained by the usual calculation based on the evaluation of the three main peaks of the technical PCB mixture (Clophen A60). During 1984-1987, 607 samples of raw milk were analysed for six single PCB components, for which legal tolerance levels became valid in 1988.(ABSTRACT TRUNCATED AT 250 WORDS)

Waste Transformer Oil and PCB Toxicity to Rainbow Trout

Young rainbow trout Salmo gairdneri (starting age, 17 d) were exposed to nominal concentrations of 0, 0.38, 0.75, 1.5, 3.0, and 6.0 μg/L total polychlorinated biphenyls (PCBs) for 90 d, then held in fresh water for 60 d. Sources of PCBs were (1) waste transformer oil containing various hydrocarbons plus a 1:2 ratio of Aroclors 1254 and 1260, and (2) pure technical PCBs of the same Aroclor ratio as that in the transformer oil. Survival of fish was much lower in transformer oil than in technical PCBs at day 90. Growth was reduced at day 30 by the transformer oil, but not until day 90 at the highest concentration of technical PCBs. Fin erosion was severe and vertebra integrity was reduced in fish exposed to transformer oil but not in fish exposed to technical PCBs. Abnormal swimming behavior of fish exposed to transformer oil was attributed to reduced volume of the swim bladder. Exposures to transformer oil decreased hematocrit, and increased serum cortisol to twice that of controls and of fish exposed to technical PCBs. Exposure to either PCB source increased disease resistance of fish to flush (external) challenges of the bacterium Yersinia ruckeri, but intraperitoneal injection of Y. ruckeri caused faster mortality of fish exposed to transformer oil than of control fish or fish exposed to technical PCBs. All routes of disease exposure should be considered in contaminant-disease interactions. Disease susceptibility or any clinical endpoints measured were never more sensitive indicators of contaminant stress than those endpoints normally examined (growth and survival) in chronic toxicity studies. Because fish took up more PCBs from the technical solutions than from transformer oil, presumably due to petroleum hydrocarbons in transformer oil, environmental assessments of PCBs should include testing the form of the material that may enter the environment.

Comparative toxicologic study with polychlorinated biphenyls in chickens with special reference to porphyria, edema formation, liver necrosis, and tissue residues

In a comparative 60-day oral toxicity test (400 ppm) in chickens, three 60%-chlorinated commercial polychlorinated biphenyl (PCB) preparations were used: compound I (Phenoclor DP6), compound II (Clophen A60), and compound III (Aroclor 1260). Using mortality, mean survival time, mean weight, and pathological observations (hydropericardium, abdominal, and subcutaneous edema and centrolobular liver necrosis) as parameters, a significant difference in toxicity was found between the compounds: compounds I and II showed the highest, compound III the lowest, toxicity. Microscopically centrolobular liver necrosis was found in chicks fed compounds I and II. Atrophy of the spleen was found in all test groups. Chemical porphyria was found as a general PCB effect: increased fecal excretion of coproporphyrin and protoporphyrin and fluorescence of tissues occurred in all test groups. Additional experiments with compound I (2000 ppm) in Japanese quail and rats confirmed the porphyrogenic action. Gas chromatographic analyses of liver and brain of dead chicks gave PCB levels that varied between 120 and 2900 ppm. The relationship of hydropericardium (chick edema) and liver necrosis to the differences in toxicity observed between the technical PCB mixtures is discussed.