Effect of chronic exposure of pcb aroclor 1254 on specific and nonspecific immune parameters in the rhesus macaca mulatta monkey. Pcbs in the environment a riskmanagement strategy for pcb. Nov 01, 2001 aroclor 1254 is defined by the weight percentage of chlorine, but the pcb congener composition varies from lot to lot. Identification and quantitation of pcb aroclor mixtures in a. Recent reports indicate substantial differences in the congener composition. Analyzing pcbs in source materials and environmental media.
Budding and tentacle regeneration were observed inhydra oligactis following exposure to the commercial pcb mixtures aroclor 1016 and 1254. Rats usually spraguedawley outbred are pretreated with aroclor 1254 or. The byproduct of this distillation was subjected to an additional chlorination step and sold as aroclor 1254. Table of aroclors polychlorinated biphenyls pcbs us epa. This light yellow viscous liquid is a particularly highly chlorinated pcb mixture which, by definition, contains 54% chlorine by weight. Pcbs in the environment do not match the pattern of congeners found in arochlor 1016. Juvenile japanese flounder were exposed to aroclor 1254 accustandard inc, nh, usa, cas 11097691 at 0 control, 10, 100, and ngl. Complete pcb congener distributions for 17 aroclor. Percent composition for some of the most toxic congeners in commercial aroclors mol%. For example, the name aroclor 1254 means that the mixture contains approximately 54 percent chlorine by weight. Program and regulatory information about this substance, including links to epa applicationssystems, statuesregulations, or other sources that track or regulate this substance. Clophen a60 is almost identical in composition to aroclor 1260 iarc 1978, while clophen a30 appears to be similar in structure to aroclor 1016. Aroclors 1221, 1242, 1248, 1254, 1260 and 1268 are com mercial pcb preparations. The source compositions are aroclor 1248 frame sample g3.
Pcb congener composition in a sediment sample collected on the west 4c2 and east sb23 side of hunters point shipyard south basin, and the pcb composition in a mixture of aroclors 1254 1260 and only aroclor. The animals were exposed to the pcbs as a component of an artificial pond water medium with pcb dilutions. Measuring pcbs as aroclors relies on there being a relatively fixed composition of pcb congeners in the mixture. Aroclor 1254 high level pcb1254h organic standards. The composition of commercial clophen a60 and phenoclor dp6 is similar to aroclor 1260. Hepatocellular carcinoma was the most frequently found lesion in animals sacrificed at the end of the experiment, observed in 2, 3, and 61% of the animals in the control, clophen a30 and clophen. The numbering standard for the different aroclors is as follows. Aroclor 1254 stock concentrate 1 mgml was made up in ethanol 50 mg aroclor 1254 was dissolved in 50 ml ethanol.
Aroclor 1016 was a refined version of aroclor 1242 that contained a lower percentage of higher and lower chlorinated congeners. The congener patterns for the threesource fingerprints were taken from aroclor standard compositions reported by frame et al. The first two digits usually refer to the number of carbon atoms in the phenyl rings for polychlorinated biphenyls this is 12. Aroclor 1254 solution certified reference material. A handbook for determining the sources of pcb contamination. Soil, water and air jim occhhialini jim okun patricia mcisaac.
Statutesregulations synonym synonym quality effective date end date. Epa region 4 technical services section issue paper for. Differential effects of two lots of aroclor 1254 on enzyme. Characterization of three aroclor mixtures using a new. Aroclor 1254 is found to be a complex mixture of polychlorinated biphenyl pcb congeners and is prepared by the chlorination of biphenyl. There were nine common pcb aroclor mixtures 1221, 1232, 1242, 1016, 1248, 1254, 1260, 1262, and 1268, and each of them has a distinctive gas chromatographic pattern.
Nov 01, 2001 composition of pcb congeners and contaminants such as pcdfs, pcdd, and pcns in two lots of aroclor 1254. However, around 1971 the formula for making aroclor 1254 changed in a fundamental way giving rise to what is now referred to as type 2 aroclor 1254. The acute toxicity of these pcb s was also compared by determining their respective 72hr lc50s. Dec 19, 2011 there were nine common pcb aroclor mixtures 1221, 1232, 1242, 1016, 1248, 1254, 1260, 1262, and 1268, and each of them has a distinctive gas chromatographic pattern. Aroclor definition of aroclor by the free dictionary. For more information about the substance, you may click one of the links below to take you to the relevant section. Als environmental does not sell chemicals, but offers analytical lab testing to determine the presence of various elements and chemical compounds.
Congenerspecific compositions of example marketed aroclors. A significant p composition of pcb congeners and contaminants such as pcdfs, pcdd, and pcns in two lots of aroclor 1254. Lighter aroclors, such as aroclor 1242, consist in some measure of lighter congeners figure 10. Polychlorinated biphenyls were once widely deployed as dielectric and coolant fluids in electrical apparatus, carbonless copy paper and in heat transfer fluids because of their longevity, pcbs are still widely in use, even though their manufacture has declined drastically since the. Aroclor conversion factors have been calculated for each of 14 pcb congeners international union for pure and applied chemistry iupac numbers 18, 28, 31, 99, 118, 128, 8, 149, 153, 180, 194, 195, 201, and 203, allowing quantification of pcb profiles as aroclors 1248, 1254, and 1260 using measurements of these congeners. In the mice fed aroclor 1254 for 11 months, hepatomas were observed in 922 41% survivors and adenofibrosis and enlarged livers in all 22 survivors. Congenerspecific tissue distribution of aroclor 1254 and. Composition of weathered, degraded, and metabolized pcb mixtures can be measured and interpreted easier using congener versus aroclor analysis. Aroclor 1254 is a widely studied commercial polychlorinated biphenyl pcb. Pcb analysis aroclors, congeners, homologs traditionally, most pcb analysis has been performed by either of two approaches aroclor analysis utilizing gas chromatography with an electron capture detector gcecd or congenerhomolog analysis utilizing high resolution gas chromatographymass spectrometry gchrms. When analyzed by gas chromatography with mass selective detection gcmsd, the number of congeners determined increased to 3. Aroclor 1254 is one of several commercial pcb mixtures that were marketed between the 1930s and 70s. Aroclor 1254 is a widely studied commercial polychlorinated biphenyl pcb mixture which, by definition, contains 54% chlorine by weight. The congener compositions of these threesource fingerprints are shown as bar graphs.
Composition of pcb congeners and contaminants such as pcdfs, pcdd, and pcns in two lots of aroclor 1254. Polychlorinated biphenyls world health organization. Aroclors are mixtures of biphenyls called congeners that are chlorinated to different extents for example, mono, di, or trichlorinated. To view more metadata about the specific synonym, click on the synonym. Dietary exposure of minks to a fraction of aroclor 1254, containing only congeners with no orthochlorines or a single orthochlorine and representing aroclor 1254, reduced litter size and fetal survival, and increased incidence of interrupted pregnancies to a similar degree as doses of the complete aroclor 1254. Production, importexport, use, and disposal chemical company produced aroclors 1221, 1232, 1242, 1248, 1254, 1260, 1262, and 1268. A polychlorinated biphenyl pcb is an organic chlorine compound with the formula c 12 h 10. Standard reference materials srms for the calibration and validation of analytical methods for pcbs as aroclor mixtures. The only exception to the naming convention is aroclor 1016, which was actually similar to the composition of aroclor 1242, with a chlorine percentage of 41. Aroclor analysis, which is the more common anajytical method applied to pcbs, has been in use for decades, and in general. Similarly, norback and weltman 1985 observed a statistically significant increase in hepatocellular carcinomas in female and male spraguedawley rats exposed to 100 ppm aroclor 1260 in the diet for 16 months, 50 ppm for 8 months, followed by. Recent reports indicate substantial differences in the congener composition among aroclor lots and hence their biologic effects.
Two lots which have been used in toxicity studies, 124191 and 6024 accustandard, were analyzed for their congener composition. This iris assessment for aroclor 1254 consists of hazard identification and doseresponse assessment data and provides support for epa risk management decisions. Aroclor 1254 is a commercial mixture of polychlorinated biphenyls pcbs, which is defined as being 54% chlorine by weight. Pcb congener composition in a sediment sample collected on the west 4c2 and east sb23 side of hunters point shipyard south basin, and the pcb composition in a mixture of aroclors 12541260 and only aroclor. Congenerspecific tissue distribution of aroclor 1254 and a. Pcb data set 1 is provided in the supplementary material on this books. Aroclor 1254 means that the mixture contains approximately. Two synthetic pcb data sets will be used for demonstration purposes. Groups of 24 rats of each sex were administered aroclor 1254 at one of three doses, either 25, 50, or 100 ppm, for 104105 weeks.
Two lots accustandard, new haven, ct that have been used in toxicity studies and are representative of commercial aroclor mixtures, 124191 and 6024, were analyzed for their congener composition 23. Aroclors 1016, 1232, 1242, 1254, and 1260 have been gravimetrically prepared in methanol and transformer oil, mixed, and transferred to amber glass ampoules in approximately 1. We use cookies to ensure that we give you the best experience of our website. These lighter congeners are the most susceptible to volatilization and water washing effects and, to a lesser extent, aerobic degradation.
Aroclors definition of aroclors by medical dictionary. Aroclor 1254 is defined by the weight percentage of chlorine, but the pcb congener composition varies from lot to lot. The toxicity of pcbs varies considerably among congeners. A definitive statistical analysis of the quantitative performance of this congener specific analysis requires detailed regression analysis of all standards, analysis of multiple replicates of sample, and multiple replicate injections. Kimbrough and linder 1974 fed 300 ppm aroclor 1254 to male balbcj mice for 11 months or for 6 months followed by the control diet for the remaining 5 months of the study. The batch chlorination process used to produce aroclors generated several congeners of the same chlorine content, in addition to congeners of higher and lower chlorine contents. The toxicity of pcbs is congenerspecific, and, therefore, measurement on an aroclor.
Congenerspecific tissue distribution of aroclor 1254 and a highly chlorinated environmental pcb mixture in rats article in environmental science and technology 3910. Matched controls consisted of groups of 24 untreated rats of each sex. Therefore gcmsd was used with the p,pcyanobiphenyl phase to characterize three pcb mixtures. The new aroclor 1016 was made by distilling aroclor 1242. Aroclor concentrations can be estimated using congener concentrations dependent on the list of congeners. Complete characterization of polychlorinated biphenyl. Table 44, and the congener composition of aroclors is shown in table 45. Identification and quantitation of pcb aroclor mixtures in.
For example, a late production aroclor 1254 lot aroclor 1254 late, with greatly. Complete characterization of polychlorinated biphenyl congeners in commercial aroclor and clophen mixtures by multldimenslonal gas. Pcb congener composition of aroclors a detailed analyses of the pcb congener distributions present in aroclors 1016, 1242, 1248, 1254, and 1260 note that the most abundant homologue groups are the di and trichlorinated biphenyls for the low chlorinated aroclors 1016 and 1242. The extent of human health effects has been debated, in part because of the use of differing risk assessment methods. Aroclor 1260 and aroclor 1254 were the main mixtures used before 1950, aroclor 1242 was the main mixture used in the 1950s and 1960s until it was phased out in 1971 and replaced by aroclor 1016. While each batch of pcbs differed slightly in its exact chemical composition based on the percentages of the the individual pcb congeners present, these differences from batch to batch were small.
Over 9 million chickens, and 60,000 pigs were destroyed because of the contamination. Example aroclors produced included aroclor 1242, 1248, 1254, and 1260, among other aroclors. Disruption of the thyroid system by the thyroiddisrupting. Aroclor synonyms, aroclor pronunciation, aroclor translation, english dictionary definition of aroclor. However, the congener composition varies from lot to lot. Pcbs sum of 120 congeners in tissues was primarily a function of lipid content of the tissues, except for the spleen, which retained more pcb than other. A bioassay of aroclor 1254 for possible carcinogenicity was conducted by administering the test chemical in feed to fischer 344 rats. Immunotoxicity studies of pcb aroclor 1254 in the adult rhesus macaca mulatta monkey preliminary report.
Als environmental performs number of test procedures for the presence of pcbs. A definitive statistical analysis of the quantitative performance of this congenerspecific analysis requires detailed regression analysis of all standards, analysis of multiple replicates of sample, and multiple replicate injections. Application aroclor 1248 may be used as a certified reference standard for the quantification of polychlorinated biphenyls pcbs in environmental matrices and transformer oil samples using chromatography. Complete pcb congener distributions for 17 aroclor mixtures determined by 3 hrgc systems optimized for conlprehensive, quantitative, congener specific analysis george m. This table shows how each list refers to the substance.