Aroclor 1260 - Explore the Science & Experts | ideXlab

Scan Science and Technology

Contact Leading Edge Experts & Companies

Aroclor 1260

The Experts below are selected from a list of 288 Experts worldwide ranked by ideXlab platform

Peter De B Harrington – 1st expert on this subject based on the ideXlab platform

  • determination of Aroclor 1260 in soil samples by gas chromatography with mass spectrometry and solid phase microextraction
    IEEE Journal of Solid-state Circuits, 2014
    Co-Authors: Mengliang Zhang, Glen P Jackson, Natalie A Kruse, Jennifer R Bowman, Peter De B Harrington

    Abstract:

    : A novel fast screening method was developed for the determination of polychlorinated biphenyls that are constituents of the commercial mixture, Aroclor 1260, in soil matrices by gas chromatography with mass spectrometry combined with solid-phase microextraction. Nonequilibrium headspace solid-phase microextraction with a 100 μm polydimethylsiloxane fiber was used to extract polychlorinated biphenyls from 0.5 g of soil matrix. The use of 2 mL of saturated potassium dichromate in 6 M sulfuric acid solution improved the reproducibility of the extractions and the mass transfer of the polychlorinated biphenyls from the soil matrix to the microextraction fiber via the headspace. The extraction time was 30 min at 100°C. The percent recoveries, which were evaluated using an Aroclor 1260 standard and liquid injection, were within the range of 54.9-65.7%. Two-way extracted ion chromatogram data were used to construct calibration curves. The relative error was <±15% and the relative standard deviation was <15%, which are respective measures of the accuracy and precision. The method was validated with certified soil samples and the predicted concentrations for Aroclor 1260 agreed with the certified values. The method was demonstrated to be linear from 10 to 1000 ng/g for Aroclor 1260 in dry soil.

  • Determination of Aroclor 1260 in soil samples by gas chromatography with mass spectrometry and solid-phase microextraction.
    IEEE Journal of Solid-state Circuits, 2014
    Co-Authors: Mengliang Zhang, Glen P Jackson, Natalie A Kruse, Jennifer R Bowman, Peter De B Harrington

    Abstract:

    A novel fast screening method was developed for the determination of polychlorinated biphenyls that are constituents of the commercial mixture, Aroclor 1260, in soil matrices by gas chromatography with mass spectrometry combined with solid-phase microextraction. Nonequilibrium headspace solid-phase microextraction with a 100 μm polydimethylsiloxane fiber was used to extract polychlorinated biphenyls from 0.5 g of soil matrix. The use of 2 mL of saturated potassium dichromate in 6 M sulfuric acid solution improved the reproducibility of the extractions and the mass transfer of the polychlorinated biphenyls from the soil matrix to the microextraction fiber via the headspace. The extraction time was 30 min at 100°C. The percent recoveries, which were evaluated using an Aroclor 1260 standard and liquid injection, were within the range of 54.9-65.7%. Two-way extracted ion chromatogram data were used to construct calibration curves. The relative error was

Donna L Bedard – 2nd expert on this subject based on the ideXlab platform

  • The Microbiology of Anaerobic PCB Dechlorination
    Organohalide-Respiring Bacteria, 2016
    Co-Authors: Jianzhong He, Donna L Bedard

    Abstract:

    The last few years have seen a great deal of progress in our understanding of microbial dechlorination of polychlorinated biphenyls (PCBs). Four new strains of Dehalococcoides mccartyi, representing all three phylogenetic subgroups, and a strain of “ Dehalobium chlorocoercia ” have been isolated and, together with two previously isolated strains of D. mccartyi , demonstrated to dechlorinate the commercial PCB mixture Aroclor 1260 . Complete genomes for five of these isolates have been published. In addition, members of the genera Dehalogenimonas and Dehalobacter have been implicated in the reductive dechlorination and respiration of PCBs. It is clear that D. mccartyi strains capable of dechlorinating Aroclor 1260 are widespread in freshwater environments, having been found in PCB-impacted sites in China, Germany, Singapore, and the USA. Pure strains of D. mccartyi that dechlorinate Aroclor 1260 by following different sets of dechlorination routes, i.e., PCB Dechlorination Processes H, N,Z, and variations of these are now available. A member of the Chloroflexi belonging to the m1/SF1 clade appears to be responsible for the dechlorination of Aroclor 1254 in a marine site. The discovery and characterization of the first three PCB reductive dehalogenases constitute a new milestone in the field. PcbA1 , PcbA4 , and PcbA5 dechlorinate Aroclor 1260 with distinct regiospecificities and prove that individual RDases can carry out the complex dechlorination of dozens of PCB congeners described by the PCB dechlorination processes . Each of these three PCB dechlorinases is bifunctional and can also dechlorinate tetrachloroethene (PCE ). PCB dechlorinators with such bifunctional PCB/PCE RDases can be selectively enriched, transferred repeatedly, and grown to high cell densities with PCE as the sole electron acceptor with no possibility of losing their ability to dechlorinate PCBs. This property makes them ideal candidates for use in bioremediation of PCBs.

  • dehalococcoides mccartyi strain jna in pure culture extensively dechlorinates Aroclor 1260 according to polychlorinated biphenyl pcb dechlorination process n
    Environmental Science & Technology, 2014
    Co-Authors: Sarah L Laroe, Ashwana D Fricker, Donna L Bedard

    Abstract:

    We isolated Dehalococcoides mccartyi strain JNA from the JN mixed culture which was enriched and maintained using the highly chlorinated commercial PCB mixture Aroclor 1260 for organohalide respiration. For isolation we grew the culture in minimal liquid medium with 2,2′,3,3′,6,6′-hexachlorobiphenyl (236–236-CB)(20 μM) as respiratory electron acceptor. We repeatedly carried out serial dilutions to extinction and recovered dechlorination activity from transfers of 10–7 and 10–8 dilutions. Fluorescence microscopy, DGGE and RFLP analysis of PCR amplified16S rRNA genes, and multilocus sequence typing of three housekeeping genes confirmed culture purity. No growth occurred on complex media. JNA dechlorinated most hexa- and heptachlorobiphenyls in Aroclor 1260 (50 μg/mL) leading to losses of 51% and 20%, respectively. Dechlorination was predominantly from flanked meta positions of 34-, 234-, 235-, 236-, 245-, 2345-, 2346-, and 2356-chlorophenyl rings, as indicated by the underscores. The major products were 24–…

  • Sediment-free anaerobic microbial enrichments with novel dechlorinating activity against highly chlorinated commercial PCBs
    Journal of Chemical Technology & Biotechnology, 2012
    Co-Authors: Vlasta Dudkova, Kateřina Demnerová, Donna L Bedard

    Abstract:

    BACKGROUND: Reductive dehalogenation by anaerobic bacteria is a promising method of detoxifying polychlorinated biphenyls (PCBs) in aquatic sediments. PCB-contaminated sediment from Str ´ a y ´ y Sewer river (Slovakia) was used as an inoculum to develop stable sediment-free enrichments with dechlorination activity directed against the commercial PCB mixture Aroclor 1260. RESULTS: Characterization of the PCBs at the site revealed that 45 mol% of the PCBs were dichlorobiphenyls and 62% of the chlorines were in the ortho-position. Both findings are characteristic of extensive dechlorination insitu. Sedimentfree enrichments with stable dechlorinating activity against Aroclor 1260 were developed by a series of transfers. These enrichments targeted hexa- through nonachlorobiphenyls and dechlorinated them to tri- through hexachlorobiphenyls by removal of flanked meta -a ndpara- chlorines when pyruvate or lactate was added as a carbon source. The known haloprimers: 4,4 � -dibromobiphenyl and 2,6-dibromobiphenyl did not influence the rate or pattern of dechlorination. The chlorophenyl rings targeted were 2,3,4,5,6- (23456-), 2346-, 2345-, 234- and 245-. CONCLUSION: The PCB dechlorination carried out by these enrichments is novel and does not correspond to any of the previously identified microbial PCB dechlorination processes or their combination. Natural attenuation processes may be under way at the Str ´ a y zsk ´ y Sewer river site. c � 2012 Society of Chemical Industry

Mengliang Zhang – 3rd expert on this subject based on the ideXlab platform

  • determination of Aroclor 1260 in soil samples by gas chromatography with mass spectrometry and solid phase microextraction
    IEEE Journal of Solid-state Circuits, 2014
    Co-Authors: Mengliang Zhang, Glen P Jackson, Natalie A Kruse, Jennifer R Bowman, Peter De B Harrington

    Abstract:

    : A novel fast screening method was developed for the determination of polychlorinated biphenyls that are constituents of the commercial mixture, Aroclor 1260, in soil matrices by gas chromatography with mass spectrometry combined with solid-phase microextraction. Nonequilibrium headspace solid-phase microextraction with a 100 μm polydimethylsiloxane fiber was used to extract polychlorinated biphenyls from 0.5 g of soil matrix. The use of 2 mL of saturated potassium dichromate in 6 M sulfuric acid solution improved the reproducibility of the extractions and the mass transfer of the polychlorinated biphenyls from the soil matrix to the microextraction fiber via the headspace. The extraction time was 30 min at 100°C. The percent recoveries, which were evaluated using an Aroclor 1260 standard and liquid injection, were within the range of 54.9-65.7%. Two-way extracted ion chromatogram data were used to construct calibration curves. The relative error was <±15% and the relative standard deviation was <15%, which are respective measures of the accuracy and precision. The method was validated with certified soil samples and the predicted concentrations for Aroclor 1260 agreed with the certified values. The method was demonstrated to be linear from 10 to 1000 ng/g for Aroclor 1260 in dry soil.

  • Determination of Aroclor 1260 in soil samples by gas chromatography with mass spectrometry and solid-phase microextraction.
    IEEE Journal of Solid-state Circuits, 2014
    Co-Authors: Mengliang Zhang, Glen P Jackson, Natalie A Kruse, Jennifer R Bowman, Peter De B Harrington

    Abstract:

    A novel fast screening method was developed for the determination of polychlorinated biphenyls that are constituents of the commercial mixture, Aroclor 1260, in soil matrices by gas chromatography with mass spectrometry combined with solid-phase microextraction. Nonequilibrium headspace solid-phase microextraction with a 100 μm polydimethylsiloxane fiber was used to extract polychlorinated biphenyls from 0.5 g of soil matrix. The use of 2 mL of saturated potassium dichromate in 6 M sulfuric acid solution improved the reproducibility of the extractions and the mass transfer of the polychlorinated biphenyls from the soil matrix to the microextraction fiber via the headspace. The extraction time was 30 min at 100°C. The percent recoveries, which were evaluated using an Aroclor 1260 standard and liquid injection, were within the range of 54.9-65.7%. Two-way extracted ion chromatogram data were used to construct calibration curves. The relative error was