title: Microwave-assisted extraction (MAE) for the determination of polybrominated diphenylethers (PBDEs) in sewage sludge.
abstract: An efficient microwave-assisted extraction (MAE) method has been developed and evaluated for the quantification of eight major polybrominated diphenylethers (PBDEs) in sewage sludge. The PBDEs were extracted from wet and dry sludge in a microwave extraction unit using a hexane/acetone mixture for 35 min at a controlled temperature of 130 degrees C. The extract was concentrated, cleaned up on a silica gel column, and analyzed by gas chromatography/mass spectrometry (GC/MS) in the negative chemical ionization (NCI) mode. The MAE procedure exhibited higher extraction efficiency, specifically for BDE (brominated diphenylether) 209, than the conventional Soxhlet extraction. The test congeners were clearly separated under specific instrumental operating conditions, at a source temperature of 230 degrees C and a column length of 20 m. The present analytical method showed recovery efficiencies ranging from 80 to 110% when applied to the PBDE-free sludge spiked with eight PBDE congeners. The efficiency of the MAE method was confirmed using sludge obtained from four sewage treatment plants (STPs). The results indicate that BDE 47, 99, and 209 are the most abundant congeners present in these sewage sludges, which is consistent with previous reports.
authors.affiliation: Aquatic Ecosystem Management Research Division, National Water Research Institute, Environment Canada, 867 Lakeshore Road, P.O. Box 5050, Burlington, ON, L7R 4A6, Canada.
authors.forename: Mari
authors.initials: M
authors.lastname: Shin
authors.forename: M Lewina
authors.initials: ML
authors.lastname: Svoboda
authors.forename: Patricia
authors.initials: P
authors.lastname: Falletta
mesh_terms: D004987:Ethers; D008401:Gas Chromatography-Mass Spectrometry; D008872:Microwaves; D011075:Polybrominated Biphenyls / Q000032:analysis*; D012722:Sewage / Q000737:chemistry*
chemical_list: D004987:Ethers; D011075:Polybrominated Biphenyls; D012722:Sewage