Biodegradation and product identification of [14C]hexabromocyclododecane in wastewater sludge and freshwater aquatic sediment

Davis, JW; Gonsior, SJ; Markham, DA; Friederich, U; Hunziker, RW; Ariano, JM

HERO ID

1443842

Reference Type

Journal Article

Year

2006

Language

English

PMID

16999116

HERO ID 1443842
In Press No
Year 2006
Title Biodegradation and product identification of [14C]hexabromocyclododecane in wastewater sludge and freshwater aquatic sediment
Authors Davis, JW; Gonsior, SJ; Markham, DA; Friederich, U; Hunziker, RW; Ariano, JM
Journal Environmental Science & Technology
Volume 40
Issue 17
Page Numbers 5395-5401
Abstract In a previous study the biodegradation of hexabromocyclododecane (HBCD) was reported to occur under realistic environmental concentrations in soils and freshwater aquatic sediments with biotransformation half-lives ranging from approximately 2 days to 2 months. In this study we extend our knowledge as to the environmental behavior of HBCD with respect to the fate of the three major diastereomers of HBCD (alpha, beta, and gamma) as well as to the identification of major intermediate metabolites formed during degradation. Substantial biological transformation of the alpha-, beta-, and gamma-[14C]HBCD diastereomers was observed in wastewater (i.e., digester) sludge and in freshwater aquatic sediment microcosms prepared under aerobic and anaerobic conditions. Concomitant with the loss of [14C]HBCD in these matrixes there was a concurrent production of three [14C]products. Using a combination of high performance liquid chromatography atmospheric pressure photoionization mass spectrometry and gas chromatography electron impact ionization mass spectrometry these metabolites were identified as tetrabromocyclododecene, dibromocyclododecadiene, and cyclododecatriene. We propose that HBCD is sequentially debrominated via dihaloelimination where at each step there is the loss of two bromines from vicinal carbons with the subsequent formation of a double bond between the adjacent carbon atoms. These results demonstrate that microorganisms naturally occurring in aquatic sediments and anaerobic digester sludge mediate complete debromination of HBCD.
Doi 10.1021/es060009m
Pmid 16999116
Wosid WOS:000240130200040
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English