Thus, the impacts of PCBs on the environment and biota are due to the individual components of these mixtures and the additive and/or nonadditive (synergistic and antagonistic) interactions among them and other chemical classes of pollutants. Quantification Method: Uses the external standard method to quantify Aroclor. However, due to biological processes, such as biodegradation and metabolism, or environmental processes, such as volatilization, congener profiles of PCBs in environmental samples are different from technical Aroclor standards. This technique is a useful screening tool for detecting concentrations of PCBs in environmental samples in the low parts-per-million (0.5–1.5 ppm) range. 1998. The extracts are cleaned up using back extraction with sulfuric acid, followed by gel permeation, silica gel, Florisil, and activated carbon chromatography. EPA 530/SW-846. Health Perspect. PCB is extracted into acetone/hexane using an automated soxhlet extraction apparatus. For PCB analysis, the methods in DIN 38 414-20 were followed. Sample may be air dried with no loss of PCB. Solvent is exchanged to hexane or other solvent for cleanup and analysis. criteria established by the Clean Water Act (Title 40 CFR part 125.58) to protect humans and wildlife are based on Aroclor values (EPA 1995). Further identification as Aroclor or congener is not possible. However, PCB analysis is plagued by the fact that PCBs are not one specific compound like most pesticides, but in fact are a class of 209 congeners. In this case, estimation of hazard based on RfDs from laboratory exposure to technical PCB mixtures would overestimate the risk. Krahn et al (1988) presents an automated HPLC cleanup method based on the size exclusion principle that has been used extensively in the NOAA NS&T program. Environ. 1998). Wet tissue is placed in a Teflon or glass extraction container along with equal amounts of anhydrous sodium sulfate and extracted with petroleum ether using a commercial high-speed blender. Toxicol. In this case, estimation of hazard based on RfDs from laboratory exposure to technical PCB mixtures would underestimate the risk. 1996b. The method is, TABLE F-4 Immunoassay Method for PCB Screening, EPA method 4020, screening for PCBs by immunoassay, 5 g of soil or sediment, or nonaqueous waste liquids, Soil samples are extracted with methanol and test kit reagents. Available Methods and Limitations Analytes Measured: The PCB congeners tested by the method include 78 individual PCB congeners and 28 co-eluting groups of two to three congeners as listed: PCB 1, PCB 3, PCBs 4/10, PCB 6, PCBs 7/9, PCBs 8/5, PCBs 12/13, PCBs 16/32, PCBs 17/15, PCBs 18, PCBs 19, PCBs 21, PCB 22, PCBs 24/27, PCB 25, PCB 26, PCB 28, PCB 29, PCB 31, PCBs 33/20, PCB 40, PCBs 41/64/71, PCBs 42/37, PCB 43, PCB 44, PCB 45, PCB 46, PCBs 47/75, PCB 48, PCB 49, PCB 51, PCB 52, PCB 53, PCBs 56/60, PCB 59 PCB 63, PCB 66, PCBs 70/76, PCB 74, PCB 82, PCB 83, PCB 84, PCB 85, PCBs 87/115/81, PCB 89, PCB 91, PCB 92, PCB 95, PCB 97, PCB 99, PCB 100, PCBs 101/90, PCB 105, PCBs 107/147, PCBs 110/77, PCB 114, PCB 118, PCB 119, PCB 124, PCB 128, PCBs 129/126, PCB 130, PCB 131, PCB 132, PCB 134, PCBs 135/144, PCB 136, PCB 137, PCBs 138/160/163, PCBs 141/1709, PCB 146, PCBs 149/123, PCB 151, PCB 153, PCB 156, PCB 158, PCB 167, PCB 169, PCBs 170/190, PCBs 171/202, PCB 172, PCB 173, PCB 174, PCB 175, PCB 176, PCB 177, PCB 178, PCB 180, PCB 183, PCB 184, PCB 185, PCBs 187/182, PCB 189, PCB 191, PCB 193, PCB 194, PCBs 195/208, PCB 197, PCB 198, PCB 199, PCB 200, PCBs 201/157, PCBs 203/196, PCB 205, PCB 206, PCB 207, PCB 209 (PCB congeners presented as PCB/PCB represent co-eluting PCB peaks under most analytical conditions. 1998, Corsolini et al. There are many gas chromatography (GC) methods for the determination of PCBs. To search the entire text of this book, type in your search term here and press Enter. PCBs play the most important role in today’s electronics industry. Within a GC system, PCBs are then detected with electron capture detection (ECD), electrolytic conductivity detection (ELCD), or mass spectrometry (MS). December. New York District./U.S. Environ. One of the variations in PCB analysis is the choice of the analytical detector, including an Electron Capture Detector (ECD), Mass Spectrometer (MS) or a High Resolution Mass Spectrometer (HRMS). [Online]. Switch between the Original Pages, where you can read the report as it appeared in print, and Text Pages for the web version, where you can highlight and search the text. An experienced laboratory will have little difficulty using the methods to determine PCBs at concentrations ranging from low parts per billion to high parts per million. The NS&T method has found general acceptance nationally because of the strong NS&T QA program that is co-administered by NOAA and National Institutes of Standards and Technology (NOAA 1993). EPA (U.S. Environmental Protection Agency). MacLeod, W.D., J.W.Brown, A.J.Friedman, D.G.Burrows, O.Maynes, R.W.Pearce, C.A.Wigren, and R.G.Bogar. Sample preparation as above. The method can analyze for all 209 congeners. Environ. All of these methods use surrogate materials added at the beginning of the process to monitor performance. We hope to divulge from the cross-section analysis process any flaws that may occur from the fabrication process. Instrumentation: High-resolution gas chromatography with low-resolution mass spectrometry (HRGC-MS). 1996b), a method that has been validated for PCB analysis in hazardous waste and environmental samples. Overview and Summary of Methods, G.G.Lauenstein and A.Y.Cantillo, eds. Method 1668, Toxic Polychlorinated Biphenyls by Isotope Dilution High Resolution Gas Chromatography/High Resolution Mass Spectrometry. 31(5):1483–1488. Single concentrations of subjectively identified Aroclors are then analyzed, and the 1016 and 1260 calibration is transformed based on the results. Discussion: The method is based on previously written EPA methods for the analysis of chlorinated dioxins and furans in environmental samples (EPA 1994). Component-based analysis or congener-specific analysis has improved the quality and the toxicological relevance of the resulting data. analytical methods of the National Status and Trends Program Mussel Watch Project: 1993–1996 Update, G.G.Lauenstein and A.Y.Cantillo, eds. By this method, interfering compounds can be identified easily and therefore false-positives can be eliminated. Quantitation of aroclors using congener-specific results. A summary of accepted extraction methods for sediments and soils, water, and biological tissue is presented below. 68-C3–309. This cell bioassay has been utilized for the screening and monitoring of Ah-active components in environmental extracts of sediment, water, air, and tissue (invertebrates, fish, birds, and mammals). The method for extracts from water, waste water, soil, sediments, biological tissue, and other environmental samples upon method validation. All the above analytical methods presented in Tables F-3 and F-4 call for at least one cleanup method to remove chemical or biological interferences with the PCB analysis. Detailed descriptions of sampling and analytical techniques for PCB’s may be found in the NIOSH Manual of Analytical Methods. The method is particularly effective at removing common interferences from environmental extracts, such as sulfur and plant or animal fats. Sci. (Reported in the NOAA NS&T: *PCB 8 is the co-eluting pair PCBs 8/5, PCB 101 is PCBs 101/90, PCB 138 is PCBs 138/160/163, PCB 170 is PCBs 170/190, and PCB 187 is PCBs 187/182.). Show this book's table of contents, where you can jump to any chapter by name. Office of Solid Waste, U.S. Environmental Protection Agency, Washington DC. Dioxins, dibenzofurans, PCBs, and colonial fish-eating water birds. Sample preparation as above. 1989. The typical Aroclor analysis is based on estimating residue PCB concentrations by measuring a subset of PCB congeners or by approximating the profile as an appropriate set of technical mixtures (Newman et al. However, the FDA has published methods for tissue, as well as NOAA NS&T. The National Academies of Sciences, Engineering, and Medicine, A Risk-Management Strategy for PCB-Contaminated Sediments, http://www.epa.gov/epaoswer/hazwaste/test/sw846.htm, Defining the Problem and Setting Management Goals, Appendix A: Biographical Information on the Committee on Remediation of PCB-Contaminated Sediments, Appendix B: Participants at the Public Sessions, Appendix F: Methods of Analysis of PCBs in Sediments, Water, and Biota. Environ. The method for the analysis of chlorinated biphenyl congeners (CBC) in water, soil, sludge, tissue (non-human), biosolid, ash, oil, and oily matrix samples is based on EPA method 1668C (using HRSM01.2 SOW). When analyzing for PCB congeners using Method 8082A, each peak is to be treated as an individual component and a standard curve is made for each of the congeners of interest. Fundam. The method separates classes of compounds based on molecular size. EPA (U.S. Environmental Protection Agency). The 18 to 78. congeners represent a subset of the total 209 possible congeners but include those most commonly found in environmental samples. Solvent concentration by Kuderna-Danish concentrator, nitrogen evaporation, or equivalent method. Sample is mixed thoroughly and blended with equal amounts anhydrous sodium sulfate. Typically for PCBs, the extracts are cleaned up using concentrated sulfuric acid cleanup. Res. Characterization of dietary exposure to planar halogenated hydrocarbons, dioxin equivalents, and biomagnification. 59(8):1187–1190. 1996). Quantification Method: Uses the four labeled PCBs, one for each level of chlorination measured (Cl4-PCB, Cl5-PCB, Cl6-PCB, and C17-PCB). 1996, Quensen et al. The environmental weathering of PCB mixtures can result in a reduction or enrichment of toxic potency over time (Quensen et al. 3rd Ed, Final Update II. Appl. 32(21):3360–3365. For MS detection of PCBs, two systems are considered: low- or medium-resolution MS and high-resolution MS. 7(3)159–171. Alumina is one of several adsorbents commercially available for this purpose. There are literally hundreds of combinations of methods currently in use for PCB extraction and cleanup, and no effort has been made for this review to be all inclusive. For sediments and soils, sample extracts are cleaned with copper and alumina. Mass-spectrometric detection of ions selective for individual congener groups provides confirmation. Solvent concentration is by Kuderna-Danish concentrator, nitrogen evaporation, or equivalent method. The sample is extracted 3× with dichloromethane using shaker or tumbler apparatus. 249–307 in Dioxins and Health, A.Schecter, ed.. New York: Plenum Press. Aroclor-based analysis and risk assessment offer minimal insight into toxicokinetics, because animals exhibit interspecies differences in their abilities to metabolize specific PCB congeners. PCB concentrations are semiquantitatively classified as below 5 ppm, between 5 and 10 ppm, between 10 and 50 ppm, and greater than 50 ppm. [Online]. Polychlorinated Biphenyls (PCBs): Environmental impact, biochemical and toxic responses, and implications for risk assessment. eA.Ÿ×oÑ9jŒŒâ§S]jÉÁöȳàåëLUõSئ\ràv ÕB–Æë’mۆlÅFf°P#|*ýÑ°GjJ”tô?w(ö”µs…³òª. The surrogate compounds are spiked into the sample, the sample is then extracted by an appropriate method, and the extract is concentrated. First, the use of single-point extrapolations assumes linear-response factors throughout the range of PCB concentrations to be analyzed, when in fact that assumption, is rarely the case. Based on feedback from you, our users, we've made some improvements that make it easier than ever to read thousands of publications on our website. 1997). PCB Congener and PCB Homologue Analysis by HRGC/LRMS: A Low MDL, Cost Effective Analytical Alternative for Tomorrow’s Quality Sensitive PCB Assessments. Standard analytical procedures of the NOAA National analytical facility, 1985–1986 (Revised). NTIS PB95–187332. 437(1):161–175. TABLE F-1 Utility of Aroclor and Congener-Specific Methods of PCBs Analysis. Click here to buy this book in print or download it as a free PDF, if available. Detection limits of individual congeners can be achieved in the lower parts per billion to parts per trillion. However, two of the most toxic and prevalent coplanar. The most common and generally considered the work-horse of PCB analysis is gas chromatography-electron capture detection (GC-ECD), the next instrument is gas chromatography (GC) with low resolution, electron ionization mass spectrometry (MS), and in recent years the industry has added the most sensitive instrument thus far for PCB congener … View our suggested citation for this chapter. The non-ortho coplanar PCBs can be more reliably measured by GC-MS because of their low concentration. Available: http://www.epa.gov/epaoswer/hazwaste/test/sw846.htm. 1998. Determination of polychlorinated biphenyls using multiple regression with outlier detection and elimination. Note that while many laboratories are interested in the analysis of PCBs by congener, most do not need, or desire, to analyze all 209. Prediction of concentrations of 2,3,7,8-TCDD equivalents (TCDD-EQ) from total concentrations of PCBs in fish fillets. TABLE F-7 Methods Appropriate for the Cleanup of Environmental Extracts for PCB Analysis. Cleanup methods—that is, laboratory techniques that remove interfering materials from extracts of environmental samples before analysis—are also presented. Solvent concentration by Kuderna-Danish concentrator, nitrogen evaporation, or equivalent method. These studies suggested a need for measuring PCBs at a congener level for application in risk assessment. Available: http://www.epa.gov/epaoswer/hazwaste/test/sw846.htm. Tillitt, D.E., J.P.Giesy, and G.T.Ankley. Guidance for Performanceing Tests on Dredged Material Proposed for Ocean Disposal. Table F-7 presents and compares several cleanup procedures suitable for the isolation of PCB from other classes of organic compounds in extracts of environmental samples. A solution of the 19 target congeners is used for a 5-point calibration. Polychlorinated dibenzo-p-dioxins, dibenzofurans, biphenyls and 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents in fishes from Saginaw Bay, Michigan. Method 8270c, Semivolatile Organic Compounds by Gas Chromatography/Mass Spectrometry (GC/MS). During this time, sample extraction and cleanup procedures have been refined, and procedures delivering MDLs in the low parts per billion are well recognized. Similarly, several other computer programs incorporating multivariate analysis have been developed to normalize PCB concentrations in samples to those in Aroclor standards (Stalling et al. MDL: The MDLs for the target congeners are 0.1 μg/kg for sediment (dry weight) and biological tissue (wet weight). Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration. Individual PCB peaks are identified by retention time. Although developments in high-resolution isomer-specific PCB analysis have enabled identification and quantification of individual PCB congeners present in commercial mixtures and environmental samples, there are important challenges associated with risk assessment of PCBs due to their different mechanisms of biological activity and toxicity. Retention and coelution database. Richter, C.A., J.B.Drake, and J.P.Giesy. Figure 1 shows the full-scan chromatogram of the standard mixture. As a result, the toxic potency of the resulting PCB mixture can be reduced by as much as 98% (Quensen et al. Method 8080A, Organochlorine Pesticides and Polychlorinated biphenyls by Gas Chromatography, Revision 1, Test Methods for Evaluating Solid Waste: Physical/ Chemical Methods, SW-846. Method 8290, Polychlorinated Dibenzodioxins (PCDDs) and Polychlorinated Dibenzofurans (PCDFs) by High Resolution Gas Chromatography/High Resolution Mass Spectrometry (HRGC/HRMS), Revision 0, Test Methods for Evaluating Solid Wastes, Physical/ Chemical Methods, SW-846. 16(4):713–724. For example, in EPA method 1625, PCBs are extracted from water along with 175 other listed compounds extracted from water. The H4IIE-luciferase induction assay is an in vitro technique for the identification of AhR-active compounds (Hilscherova et al. Jinghongyi Pcb (Hk) Co., Limited have been specialized in Pcb Prototype manufacture for many years. This procedure destroys most organic chemicals, including most pesticides and other compounds that interfere with the PCB HRGC-ECD analysis. Revision 3, Test Methods for Evaluating Solid Wastes, Physical/Chemical Methods, SW-846. 1996. Contam. The surrogate compounds are spiked into the sample, the sample is then extracted by an appropriate method, and the extract is concentrated. Thus, ELISA is rapid and less expensive than traditional methods. Concentrations of total PCDFs and PCNs in Aroclor preparations were in the ranges of 0.6 to 7.5 μg/g and 2.6 to 170 μg/g, respectively. Technol. Environ. 3. Method 1668 is currently being revised to expand the full list of 209 PCB congeners. The ELISA method is based on the specific binding of PCB to antibodies and requires little effort for sample extraction or cleanup. Thermal design and thermal analysis are important to increase PCB reliability. Instead of prescriptive methods, the federal and state agencies using PCB data establish quality-assurance requirements, including matrix-specific performance data. Michigan State University, Aquatic Toxicity Laboratory. The GC-MS method provides better precision and resolution than the GC-ECD techniques. 2000. 1992. For example, advanced numerical analysis using hierarchical cluster analysis (H.A.) Discussion: This PCB congener method by low-resolution mass spectrometry is a performance-based method based on EPA method 8270b (EPA. Quantification Method: Uses the external standard method with all the above listed PCB congeners. Pp. Aroclor analysis is recommended only for compliance measurements where Aroclor concentrations need to be specified. Our main products are various kinds of Flexible PCB. Newman, J.W., J.S.Becker, G.Blondina, and R.S.Tjeerdema. The H4IIE rat hepatoma cell bioassay (Tillitt et al. The sample is extracted with supercritical CO2. Van den Berg, M., L.Birnbaum, A.T.C.Bosveld, B.Brunström, P.Cook, M.Feeley, J.P.Giesy, A.Hanberg, R.Hasegawa, S.W.Kennedy, S.W., T.Kubiak, J.C. Larsen, F.X.van Leeuwen, A.K.Liem, C.Nolt, R.E.Peterson, L.Poellinger, S. Safe, D.Schrenk, D.Tillitt, M.Tysklind, M.Younes, F.Waern, and T. Zacharewski. The method detection limits (MDLs) for Aroclors vary in the range of 0.054 to 0.9 mg/L in water and 57 to 70 ng/g in soils, with higher MDLs for the more heavily chlorinated Aroclors. The cost on a per sample basis ranges from $50 to $500, depending on the sample matrix, number of samples to be analyzed, and extent of quality-assurance-quality-control protocols. The internal standards are added to the clean extract, and the sample is analyzed by HRGC-MS. 1987. It can also be used to direct fractionation steps in a toxicity identification and evaluation approach and to detect novel compounds that have biological activity similar to that of TODD. 1992. 1998. 17(11):2159–2167. This level of sensitivity is not sufficient for monitoring PCBs in environmental samples but may be applied for highly contaminated sediments and for evaluating the effectiveness of sediments dredging operations (Ritcher et al. Sample is mixed thoroughly and blended with equal amounts drying agent (sodium sulfate). For a sample size of 20 g of tissue or soil and a final extract volume of 0.25 mL, the H4IIE-luc assay will detect 1 part per trillion (ppt; pg/g of wet weight) TODD-equivalents. Solvent concentration by Kuderna-Danish concentrator, nitrogen evaporation, or equivalent method. MDL: The MDL ranges from 57 to 70 μg/kg of soil and from 0.054 to 0.090 μg/L of water. EPA (U.S. Environmental Protection Agency). Acid cleanup is generally followed by alumina or other adsorption column cleanup to further isolate PCB. Solvent concentration by Kuderna-Danish concentrator, nitrogen evaporation, or equivalent method. Analytes Measured: The 13 congeners tested by the method include PCB 77, PCB 105, PCB 114, PCB 118, PCB 123, PCB 126, PCB 156, PCB 157, PCB 167, PCB 169, PCB 170, PCB 180, and PCB 189.
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