Chlorobiphenyl (PCB) composition of extracts of subsurface soil, superficial dust and air from a contaminated landfill

Samples of 3 matrices (air, superficial dust and subsurface soil) from an aged PCB-containing landfill were extracted and the extracts refined for bioassay. Acetone: hexane extraction was modestly selected for non-planar compounds. Coplanar PCBs and PCDFs were enriched about 2-fold in the subsequent benzene:methylene chloride extracts of the soil. Extract refinement with Florisil slurry and alumina column chromatography did not appreciably change the composition of the extracts. CB 28 (2,4,4′-triCB) dominated in all extracts. The congener composition of soil and air were surprisingly similar, being enriched in tri- and tetraCBs while dust retained higher proportions of congeners with 4 and 5 chlorines. It is postulated that anaerobic dechlorination in the moist subsurface soil depleted the higher chlorinated congeners; more volatile congeners escaped into the atmosphere while moderately chlorinated congeners were trapped in the superficial dust and debris. The refined extracts represent distinct compositions of environmental PCB mixtures suitable for bioassay.     

Chlorobiphenyl (PCB) composition of extracts of subsurface soil, superficial dust and air from a contaminated landfill

Samples of 3 matrices (air, superficial dust and subsurface soil) from an aged PCB-containing landfill were extracted and the extracts refined for bioassay. Acetone:hexane extraction was modestly selected for non-planar compounds. Coplanar PCBs and PCDFs were enriched about 2-fold in the subsequent benzene:methylene chloride extracts of the soil. Extract refinement with Florisil slurry and alumina column chromatography did not appreciably change the composition of the extracts. CB 28 (2,4,4′-triCB) dominated in all extracts. The congener composition of soil and air were surprisingly similar, being enriched in tri- and tetraCBs while dust retained higher proportions of congeners with 4 and 5 chlorines. It is postulated that anaerobic dechlorination in the moist subsurface soil depleted the higher chlorinated congeners; more volatile congeners escaped into the atmosphere while moderately chlorinated congeners were trapped in the superficial dust and debris. The refined extracts represent distinct compositions of environmental PCB mixtures suitable for bioassay. Received: 21 November 1995 / Revised: 9 April 1996 / Accepted: 14 April 1996     

Certification of SRM 1589a PCBs,pesticides, PBDEs,and dioxins/furans in human serum

The Certificate of Analysis for SRM 1589a PCBs, Pesticides, PBDEs, and Dioxins/Furans in Human Serum has been updated to include certified concentration values for 27 polychlorinated biphenyl (PCB) congeners, three chlorinated pesticides, and four polybrominated diphenyl ether (PBDE) congeners as well as reference concentration values for 27 additional PCB congeners, six additional chlorinated pesticides, three additional PBDE congeners, and selected polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). This represents an addition of concentration values for 29 PCB congeners and for PBDE congeners that were not quantified in the previous issue of SRM 1589a. With the increased number of certified and reference concentration values for PCBs and the inclusion of certified and reference concentration values for PBDEs, this serum material will be more useful as a reference material for contaminant monitoring in human tissues and fluids. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Levels of polychlorinated biphenyls in the lower troposphere of the North- and South-Atlantic Ocean

Summary Fourteen polychlorinated biphenyl (PCB) congeners were quantified in air samples of the tropospheric boundary layer of the Atlantic Ocean. The samples were taken on the German research vessel Polarstern during north-south cruises across the Atlantic Ocean (1990, 1991), and on the Capo Verde islands in the North Atlantic Ocean (1992). Values for the sum of PCB were between 48 pg/m³ (values for the seven indicator congeners were [in pg/m³]: PCB 28: 1.3; PCB 52: 5.0; PCB 101: 3.0; PCB 118: 0.5; PCB 138: 1; PCB 153: 1; PCB 180: <0.2) in the Westwind Belt of the eastern North Atlantic and 22 pg/m³ (values for the seven indicator congeners were [in pg/m³]: PCB 28: 2.3; PCB 52: 3.4; PCB 101: 0.5; PCB 118: <0.2; PCB 138: <0.2; PCB 153: <0.2; PCB 180: <0.2) in the Westwind Belt of the central South Atlantic. Up to 385 pg/m³ (values for the seven indicator congeners were [in pg/m³]: PCB 28: 2.6; PCB 52: 11.7; PCB 101: 28.4; PCB 118: 9; PCB 138: 21; PCB 153: 18; PCB 180: 5.5) were measured of the coast of South Patagonia. A difference depending on latitude and on terrestrial influenced air masses between the lower and the higher chlorinated congeners was observed. The levels of three- and tetrachlorinated congeners were highest in the Trade Wind regions. The contents of the higher chlorinated congeners had maxima in samples influenced by continental air masses. A correlation of the levels of the lower chlorinated congeners in air over the South Atlantic with the surface water temperature and thus with the temperature dependent gas/water partition coefficient K_gw was observed. Part XVI: Fischer RC, Krämer W, Ballschmiter K (1991) Chemosphere 23:889–900     

Resin‐supported palladium nanoparticles as recyclable catalyst for the hydrodechlorination of chloroarenes and polychlorinated biphenyls

This study focuses on the hydrodechlorination of chlorinated arenes as well as polychlorinated biphenyls (PCBs) utilizing a resin‐supported Pd(0) catalyst. Bearing in mind the dangers associated with toxic PCBs, treatment of the remnants of industrial wastes containing PCB congeners is indispensable. One such method is reductive hydrodechlorination. Instead of utilizing traditional sources of hydrogen, ammonium formate is used for in situ hydrogen generation. Moreover, palladium nanoparticles are supported on an anionic exchange resin which makes the process recyclable with a negligible change of yield after recycling experiments. The catalyst is demonstrated in the hydrodechlorination of a wide range of chlorinated compounds and PCB congeners including aroclors 1242, 1248 and 1254. Copyright © 2016 John Wiley & Sons, Ltd.     

Diol sep-pak cartridges for enrichment of polychlorobiphenyls and chlorinated pesticides from water samples; determination by GC-ECD

Summary Gas chromatography of polychlorinated biphenyls and chlorinated pesticides in water samples has been performed after adsorption from a 20–200-mL sample on to a cartridge containing 100 mg diol-bonded porous silica. The PCBs are desorbed with 500 μL ethyl acetate, which is concentrated and analysed by gas chromatography with electron-capture detection (GC-ECD). The average recovery of 0.1 ng mL⁻¹ PCB congeners from distilled water and from Aniene river water is≥95% (standard deviation≤2.8). Average recoveries of 25 ng mL⁻¹ Aroclor 1254 from distilled water and from Aniene river water were, respectively, 94.4% and 92.5% (standard deviation 5.8). In the separation of PCB congeners from the chlorinated pesticides only the aldrin (40%) was eluted with the PCBs from the diol Sep-Pak cartridge by aqueous methanol. The method described is simple and reproducible.     

Gas chromatographic separation of polychlorinated biphenyls on a new apolar capillary column

Eighty one polychlorinated biphenyls (PCBs) and nineteen chlorinated pesticide standards have been analyzed on a newly developed apolar high resolution gas chromatography (HRGC) column. Emphasis was placed on the determination of PCB indicator congeners which are part of national regulations, and of toxic coplanar PCB congeners. The new column enables almost unambiguous quantification of the PCB indicator congeners (PCB 138 can be separated from both PCB 163 and PCB 164; PCB 28 and PCB 31 were also separated and no coelution was observed for PCB 52, PCB 118, and PCB 180). The new column furnished better results than CP-Sil 8 for the analysis of PCB indicator congeners in a sample of seal blubber.     

Bio Availability of Polychlorinated Biphenyl Congeners in the Soil to Earthworm (L. rubellus) System

Abstract

The earthworm's (Lumbricus rubellus) uptake of polychlorinated biphenyls (PCBs) from a soil contaminated with a commercial PCB formulation (Askarel at 150 μg g^?1) and their elimination of PCBs into a low contaminated soil (15 μg g^?1) has been studied. 17 individual congeners were monitored. The uptake and the elimination rate were similar for all PCB congeners notwithstanding their different chloro-substitution pattern which suggested that bioaccumulation of PCBs in earthworms is governed by passive, possibly diffusion controlled processes. The equilibrium state in the three-phase system, soil/soil water/earthworm was reached with a half-time around 3–4 days. The soil to earthworm bioconcentration factor ranged from 4 to 20 for tetra- to octa-chlorinated biphenyls and was weakly depending on the octanol-water partition coefficient: BCF = ?(1.3?1.8) × K _OW ^(0.35?0.40).     

Catalytic dechlorination of Aroclor 1242 by Ni/Fe bimetallic nanoparticles

Ni/Fe bimetallic nanoparticles were synthesized for treatment of Aroclor 1242, in order to evaluate their applicability for in situ remediation of groundwater and soil contaminated by polychlorinated biphenyls (PCBs). Our experimental results indicate that the total PCB concentration changed during the reduction of 3,5-dichlorobiphenyl (PCB 14), and biphenyl was produced as the final product. Initially, the concentration of 3-chlorobiphenyl (PCB 2) was increased in the prophase reaction and then slowly decreased, suggesting that Aroclor 1242 was first adsorbed by Ni/Fe nanoparticles, and then, the higher chlorinated congeners were converted gradually to the lower chlorinated congeners, and finally to biphenyl. The dechlorination efficiency of Aroclor 1242 reached approximately 80% at 25°C in just 5h, then 95.6% and 95.8% in 10h and 24h, respectively. The study revealed that high Ni/Fe nanoparticle dosage and high Ni content in Ni/Fe nanoparticles favor the catalytic dechlorination reaction. Moreover, a comparison of different types of catalysts on the dechlorination of Aroclor 1242 indicated that Ni/Mg and Mg powders showed a greater reactivity than Ni/Fe and Fe nanoparticles, respectively.     

Monitoring of di-(2-ethylhexyl)phthalate,nonylphenol, nonylphenol ethoxylates,and polychlorinated biphenyls in anaerobic and aerobic sewage sludge by gas chromatography–mass spectrometry

The occurrence of di-(2-ethyhexyl)phthalate (DEHP), nonylphenol and nonyphenol mono- and diethoxylates (NPEs) and seven polychlorinated biphenyl (PCB) congeners in different types of sludge samples is reported. The analysis of these compounds was carried out by sonication-assisted extraction and analytical determination by gas chromatography coupled with a mass spectrometry detector, following a previously described method. The applicability of the method was tested by monitoring the organic pollutants in primary, secondary, mixed, and digested-dehydrated sludge samples from two wastewater treatment plants (WWTPs) based on aerobic and on anaerobic biological stabilization. The occurrence of these compounds in sewage sludge and the influence of sludge stabilization process on the further farmland application of the sludge were evaluated. DEHP and NPEs were detected in all analysed sludge samples from both WWTPs at concentration levels in the range of 22.3–601?mg?kg^?1 and 136–2357?mg?kg^?1 dm (dry matter), respectively. PCBs were detected in all types of sludge analysed from the anaerobic WWTP but was not detected in any sludge sample from the aerobic WWTP. Concentration levels of the sum of the seven PCBs congeners were up to 1.5?mg?kg^?1 dm. The concentration of DEHP, sum of NPEs, and sum of the seven PCB congeners were higher than the limits fixed in the third draft of the future Sludge Directive for land application of sludge in the 67%, 100%, and 11% of samples from the anaerobic WWTP and in the 83%, 92%, and 0% of samples from the aerobic WWTP, respectively.     

Isolation of Biphenyl and Polychlorinated Biphenyl-Degrading Bacteria and Their Degradation Pathway

Four strains of biphenyl-degrading bacteria were isolated from a sewage and identified from the Rhodococcus genus (SK-1, SK-3, and SK-4) and Aquamicrobium genus (SK-2) by 16S rRNA sequence. Among these strains, strain SK-2 was most suitable for biphenyl degradation. When 0.65, 1.3, 2.6, or 3.9 mM of biphenyl was used, the biphenyl was completely degraded within 24 and 96 h of culture, respectively. However, in the case of 6.5 and 9.75 mM of biphenyl, the biphenyl degradation yields were about 80 % and 46.7 % after 120 h of culture, respectively. The isolated strains could degrade a broad spectrum of aromatic compounds including high-chlorinated polychlorinated biphenyl (PCB) congeners in the presence of biphenyl. In addition, strain SK-2 could utilize PCB congeners containing one to six chlorine substituents such as 2,2′,4,4′,5,5′-hexachlorobiphenyl. The PCB utilization rate by the strain SK-2 was increased compared to that of other PCB congener-utilizing bacteria. The four isolates metabolized 4-chlorobiphenyl to 4-chlorobenzoic acid and 2-hydroxy-6-oxo-6-(4′-chlorophenyl)-hexa-2,4-dienoic acid. These results suggest the isolated strains might be good candidates for the bioremediation of PCB-contaminated soil, especially high-saline soils.     

Determination of polychlorinated biphenyl congeners and chlorinated pesticides in a fish tissue standard reference material

The concentrations of a wide range of polychlorinated biphenyl congeners (PCBs) and chlorinated pesticides in a fish tissue Standard Reference Material (SRM) have been determined using multiple methods of analysis. This material, SRM 1946, Lake Superior Fish Tissue, was recently issued by the National Institute of Standards and Technology (NIST) and complements a suite of marine environmental natural-matrix SRMs that are currently available from NIST for the determination of organic contaminants such as aliphatic hydrocarbons, polycyclic aromatic hydrocarbons (PAHs), PCBs, and chlorinated pesticides. SRM 1946 is a fresh tissue homogenate (frozen) prepared from filleted adult lake trout (Salvelinus namaycush namaycush) collected from the Apostle Islands region of Lake Superior. SRM 1946 has certified and reference concentrations for PCB congeners, including the three non- ortho PCB congeners, and chlorinated pesticides. Certified concentrations are available for 30 PCB congeners and 15 chlorinated pesticides. Reference concentrations are available for 12 PCB congeners and 2 chlorinated pesticides. In addition, SRM 1946 is characterized for additional chemical constituents and properties: fatty acids, extractable fat, methylmercury, total mercury, selected trace elements, proximates, and caloric content. The characterization of chlorinated compounds is described in this paper with an emphasis on the approach used for the certification of the concentrations of PCB congeners and chlorinated pesticides. The PCB congener and chlorinated pesticide data are also compared to concentrations in other marine natural-matrix reference materials available from NIST (fish oil, mussel tissue, whale blubber, and a second fresh frozen fish tissue homogenate prepared from filleted adult lake trout collected from Lake Michigan) and from other organizations such as the National Research Council Canada (ground whole carp), the International Atomic Energy Agency (fish homogenate), and the European Commission Joint Research Centre [fish oils (cod and mackerel) and mussel tissue].     

Degradation of PCB by Bacteria Isolated from Long-Time Contaminated Soil

Abstract

Four bacterial isolates belonging to the genera Pseudomonas and Alcaligenes were obtained by the enrichment method, using biphenyl as the sole carbon source, from the soil, which underwent long-time contamination with technical mixtures of PCB. Kinetics of PCB degradation by individual isolates was measured using n-hexane extraction of the cultivation media in proper time intervals and analysed by congener specific gas chromatography with electron capture detection. All isolates exhibit interesting biodegradative potential. Specific degradation of individual congeners with respect to the number and position of chlorine substituents is discussed. The influence of glucose, biphenyl and 3-chlorobenzoic acid on the PCB degradation has been assessed.     

Polychlorinated biphenyls,dibenzo-p-dioxins and dibenzofurans in soil samples from airport areas of Croatia

Levels and patterns of polychlorinated biphenyls (PCBs) were studied in surface soil samples collected in the coastal part of Croatia within and surrounding four different airports and in the vicinity of two partially devastated electrical transformer stations. The compounds accumulated from air-dried soil samples by multiple ultrasonic extraction with an n-hexane?:?acetone 1?:?1 mixture were analysed by capillary gas chromatography with electron capture and ion-trap detection. PCBs were quantified against a standard Aroclor 1242/Aroclor 1260 mixture and a standard mixture of 17 individual PCB congeners (IUPAC No.: 28, 52, 60, 74, 101, 105, 114, 118, 123, 138, 153, 156, 157, 167, 170, 180, and 189). The mass fractions of total PCBs in 18 soil samples collected within the airport premises ranged from 3 to 41?327?µg/kg dry weight (dw) (median: 533?µg/kg?dw), and those in 21 samples collected at a distance ranging from several metres to 5?km away from the airport fence, from <1 to 39?µg/kg?dw (median: 5?µg/kg?dw). The highest PCB levels were determined in soils along the airport aprons where the aircrafts were serviced and refuelled. The PCB pattern was very similar to technical Aroclor 1260 in all airport soils. The PCB pattern in 22 soils collected in the vicinity of electrical transformer stations was dominated by congeners contained in Aroclor 1242. These soils contained 7 to >400?µg/kg?dw of total PCBs. One highly PCB-contaminated airport soil sample was analysed for polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs). With an international toxic equivalent (I-TEQ) of 9.7?ng/kg?dw, the airport soil contamination was within values typical for urban and rural areas, and the congener patterns gave no clear indication for PCBs as the only source of PCDDs/PCDFs.     

Toxic Congener-Specific Analysis of PCBs: Assessment of Toxicity in Equivalents of TCDD

Abstract

High resolution capillary gas chromatographic analysis of the polychlorobiphenyls (PCBs) present in snapping turtle eggs, provided quantitative data on selected toxic congeners. The concentrations of these congeners have been converted into equivalent toxic concentrations of 2,3,7,8-tetrachloro-p-dibenzodioxin (TCDD). The toxic equivalent factors (TEFs), necessary to effect this transformation were derived from EC₅₀ values (half the concentration of the toxic congener required to produce the maximum effect) for aryl hydrocarbon hydroxylase (AHH) induction associated with the corresponding toxic PCB congener or isomer. Summation of the resulting toxic equivalents provided a composite assessment of the toxlcity of the PCB mixture in terms of an equivalent concentration of TCDD.     

Analysis of Toxaphene (PCC) and Chlordane in Biological Samples by NCI Mass Spectrometry

Abstract

Several recent reports indicate that both toxaphene (polychlorocamphene, PCC) and chlordane are widespread pollutants in our environment. These insecticides, both complex mixtures of chlorinated hydrocarbons, are difficult to separate from each other. Thus the analyses of them in environmental samples are difficult and furthermore complicated by interferences from other chlorinated hydrocarbons such as PCB and DDT compounds. Mass fragmentography using the negative ions formed by chemical ionization proved to be useful to selectively detect the toxaphenes and the chlordanes without interferences from DDT. High concentrations of PCB still influence on the results and have to be removed in the clean-up procedure.     

Polychlorinated naphthalene concentrations and profiles in cheese and butter,and comparisons with polychlorinated dibenzo-p-dioxin,polychlorinated dibenzofuran and polychlorinated biphenyl concentrations

Polychlorinated naphthalenes (PCNs) are candidates for inclusion in the Stockholm Convention on persistent organic pollutants. PCNs are structurally and toxicologically similar to 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) and its analogues. Intake in food is considered to be an important human exposure pathway for PCNs. In this preliminary study, cheese and butter samples were analysed for PCNs, polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs) using an isotope dilution gas chromatography high-resolution mass spectrometry method. The aim of this study was to evaluate the PCN concentrations in the cheese and butter samples and to compare them with the PCDD, PCDF and PCB concentrations. The PCN concentrations were 5.6–103 pg g^?1 of wet weight in the seven cheese samples tested and 5.0–199 pg g^?1 of wet weight in the seven butter samples tested. The mass concentrations of lower chlorinated congeners were greater than those of the higher chlorinated congeners. Congeners of CN45/36, CN27/30 and CN33/34/37 were much more abundant than other congeners found in tetrachlorinated PCNs. Congeners of CN51, CN66/67 and CN73 were determined to be the predominant congeners in penta-, hexa- and heptachlorinated homologs, respectively. The PCNs contributed around 5% of the total PCN, PCDD, PCDF and PCB toxic equivalence (TEQ) values. CN73 was found to be the dominant PCN congener and contributed more than 40% to the PCN TEQ value. Congeners CN66/67, CN69 and CN63 were also found at relatively high levels. The PCB congener CB118 was the predominant congener (by mass-based concentration) of the 12 dioxin-like PCBs (dl-PCBs). The PCBs contributed 53.8% of the total TEQ, and congener CB126 contributed more than any other compound that was analysed to the total TEQ. The PCDDs and PCDFs contributed 11.6% and 29.7% of the total TEQ values, respectively.     

Determination of 26 polychlorinated biphenyls congeners in soil samples using microwave-assisted extraction with open vessel and gas chromatography

A procedure focused on microwave-assisted extraction in open vessel (MAE-OV) and gas chromatography with electron capture detection (GC-ECD) was used for the determination of 26 congeners of polychlorinated biphenyls (PCBs) in soil samples. The limit of detection (LOD) and limit of quantification (LOQ) were evaluated for commercial PCBs mixture Aroclor1260. LOD and LOQ were calculated for each PCB congener, in the ranges (0.03–0.27?ng?g^?1) and (0.11–0.70?ng?g^?1), respectively. After optimization, 26 PCBs congeners were successfully extracted from soil samples with recovery amounts ranging between 84.7% and 117.3% for all PCBs congeners. The evaluated method of MAE-OV showed good separation and extraction of all PCBs congeners from soil samples. Extraction parameters such as solvent choice, power and extraction time were investigated. This study indicated that MAE-OV could be an interesting alternative method to extract PCBs from soils, since it is economical, easy, fast and requires low amounts of solvents.     

Quantitative determination of toxic mono- and non-ortho polychlorinated biphenyls in cod liver oil after selective liquid chromatographic separation

Summary By application of chromatographic column filled with Supelclean ENVI-Carb/Celite and elution with three solvents of different polarity three PCB fractions were obtained. Fraction A contained poly-ortho PCBs, Fraction B mono-ortho PCBs, and Fraction C non-ortho PCBs. The Supelclean ENVI-Carb/Celite column was used in combination with a sample preparation procedure for pre-cleaning of acid-stable chlorinated hydrocarbons such as DDT and its metabolites, HCH isomers, and regulation-relevant PCB congeners. The method was optimized using standard solutions of 55 PCB congeners, 8 chlorinated pesticides and contaminated cod liver oil samples. The influence of traces of remaining matrix on the elution profile of the organochlorine compounds on Supelclean ENVI-Carb/Celite was observed. Quantitation was carried out by GC-ECD with fused silica capillary columns of different polarity.     

Comparison of methods for the gas-chromatographic determination of PCB congeners and chlorinated pesticides in marine reference materials

Summary Three gas-chromatographic (GC) columns with different selectivity (DB-5, DB-1701, and C-18) and two different GC detectors (electron-capture and mass-spectrometric) were used to analyze three Standard Reference Materials (SRMs), which are available from the National Institute of Standards and Technology (NIST), and two Certified Reference Materials (CRMs), which are available from the Community Bureau of Reference (BCR), for polychlorinated biphenyl (PCB) congeners and chlorinated pesticides. The materials analyzed were: SRM 1588, Organics in Cod Liver Oil; SRM 1941, Organics in Marine Sediment; SRM 1974, Organics in Mussel Tissue (Mytilus edulis); CRM 349, Chlorobiphenyls in Cod Liver Oil; and CRM 350, Chlorobiphenyls in Mackerel Oil. Results from these different methods are compared, and concentrations for additional PCB congeners and chlorinated pesticides in these reference materials, which have not been measured previously, are reported.Dedicated to Professor Dr. Wilhelm Fresenius on the occasion of his 80th birthday