Determination of organophosphate flame retardants in sediments by microwave-assisted extraction and gas chromatography-mass spectrometry with electron impact and chemical ionization.

An efficient microwave-assisted extraction (MAE) procedure coupled to gas chromatography-mass spectrometry (GC-MS) with electron impact (EI) and chemical ionization (CI) has been developed to determine five organophosphate flame retardants (OPFRs) in marine and river sediments. The effects of various operating parameters on the quantitative extraction of the OPFRs through MAE were systematically investigated. Selected OPFRs were extracted from the sediments through MAE using 40 mL of acetone at 120 degrees C for 20 min. The limits of quantitation ranged from 0.1 to 0.4 ng/g (dry weight) in 2 g of the sediment samples. Moreover, as the chlorinated alkyl phosphates present no molecular ions in EI, GC-MS with furan-CI (furan-CI) was applied to confirm their determination in complex environmental samples. The recoveries of the selected OPFRs in spiked sediment samples ranged from 62% to 106% (relative standard derivation, 1-11%). The total concentrations of the selected OPFR residues in marine and river sediments ranged from 1.0 to 12.6 ng/g.