Invariant chlorine isotopic signatures during microbial PCB reductive dechlorination.
In order to develop more robust insight into the natural attenuation of polychlorinated biphenyls (PCBs), the chlorine isotopic composition of residual 2,3,4,5-tetrachlorobiphenyl (2,3,4,5-CB) was monitored as it underwent microbial reductive dechlorination to 2,3,5-trichlorobiphenyl (2,3,5-CB) in laboratory cultures. Reverse-phase high performance liquid chromatography (HPLC) was employed to isolate the former compound from the experimental matrix for delta37Cl measurement. No detectable isotopic fractionation was observed over the 90 day incubation with sterile control, standard, and inoculated samples all exhibiting delta37Cl values with a range of approximately 0.5 per thousand. These results show that this type of biological activity can be discriminated from other transformations by the absence of a measurable isotope effect during microbial reductive dechlorination. The utility of HPLC isolation for compound-specific delta37Cl analyses of environmentally relevant species is also demonstrated.
Drenzek
Nicholas J
NJ
Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA. ndrenzek@whoi.edu
Eglinton
Timothy I
TI
Wirsen
Carl O
CO
Sturchio
Neil C
NC
Heraty
Linnea J
LJ
Sowers
Kevin R
KR
Wu
Qingzhong
Q
May
Harold D
HD
Reddy
Christopher M
CM
D001419:Bacteria / Q000378:metabolism*; D001711:Biotransformation; D002713:Chlorine / Q000032:analysis* / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D004785:Environmental Pollutants / Q000032:analysis / Q000378:metabolism*; D007554:Isotopes; D010084:Oxidation-Reduction; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000378:metabolism*
D004785:Environmental Pollutants; D007554:Isotopes; D002713:Chlorine; D011078:Polychlorinated Biphenyls