Multiresidue determination of phosphoric acid triesters in fish, sea sediment and sea water

An analytical method was developed for determining residue of phosphoric acid triesters (tri-n-butyl phosphate, tris (2-chloroethyl) phosphate, tri-n-amyl phosphate, tris (2, 3-dichloropropyl) phosphate, triphenyl phosphate, tris (2-butoxyethyl) phosphate, tricresyl phosphate, tris (2, 3-dibromopropyl) phosphate, tris (4-tert-butylphenyl) phosphate in fish, sea sediment and sea water. Phosphoric acid triesters were extracted from these materials with acetonitrile and methylene chloride. After n-hexane-acetonitrile partition, the extract was cleaned up by activated charcoal column chromatography, followed by extraction with conc. sulfuric acid, washing with 0.5N sodium hydroxide solution, and finally Florisil minicolumn chromatography. The purified extracts were analyzed with a gas chromatograph equipped with a flame photometric detector (P-filter) and with a gas chromatograph-mass spectrometer. The separation on gas chromatography was found to be good with 10% OV-1 on Chromosorb W experiments (AW-DMCS) and 5% FFAP on Gas Chrom Q. Throughout the present method, the recoveries of phosphoric acid triesters were in the range of 60-95%, and the detection limits (fish) were approximately 1-5μg/kg.