PM07 Pollutant Chemistry Transport, Cycling and Fate
Exhibit Hall
8:00 AM - Monday
(PM101) Vertical Profile of Brominated Flame Retardants in Sediment Cores from Great Lakes, North America.
Zhu, LY1, Hites, RA1, 1 School of Public and Environmental Affairs, Bloomington, IN, 47405
ABSTRACT- The analysis of sediment cores is an elegant way to study the history of persistent organic pollutants in the environment. The vertical profiles of some brominated flame retardants, including polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), and one major polybrominated biphenyl congener (PBB-153), were studied in dated sediment cores taken from Lake Erie and Lake Michigan in 2003 and 2004. The sedimentary burdens of total PBDEs increased rapidly from the early 1970s with a doubling time of 4 years. BDE-209 was found to be the predominant congener in the sediment core beginning in 1979. The total PBDE flux to this area was 43 ng cm-2 yr-1 at its peak year in 2000. The total concentrations of the PBDEs in the sediment, excluding BDE-209, correlated very well with the total PBDEs in fish samples as a function of time. PBBs were widely used in North America as flame retardants in the early 1970s, but they were banned in 1976 in the US. In this study, PBB-153 was found to increase rapidly during the1970s, peak around 1980, and decline and level off from the late 1990s. There is a shift of the peak time of PBB between the market usage and the deposition in the sediment.
Key words: sediment cores, Brominated flame retardants, polybrominated diphenyl ethers, hexabromocyclododecane