title: Comparison of accelerator mass spectrometry with gas chromatography for the determination of pesticide residues in individual items in the diets of wild birds and mammals.
abstract: Methods to refine the assessment of exposure of wild birds and mammals to pesticides required measurement of pesticide residues in very small samples of their diets. Sample sizes were in the 1-100 mg range, and the target residue for measurement was 0.01 mg/kg. Gas chromatography-mass spectrometry (GC-MS) with large volume injection was compared with the use of an accelerator mass spectrometer (AMS) to measure residues of pesticide labeled at near-background levels with carbon-14. The GC-MS method was able to detect residues down to 0.1 ng per item of diet, and the AMS detected the radiolabel down to 1 mBq (0.06 disintegration per minute, 1 ng of pesticide at the specific activity used) per sample. The target residue level was achieved by the GC-MS method for samples down to 10 mg. The GC method appeared to be best suited to monitoring residues in field studies, and the AMS shows great potential for use in laboratory experiments concerning pesticide degradation.
authors.affiliation: Central Science Laboratory, Sand Hutton, York, YO41 1LZ, United Kingdom. p.brown@csl.gov.uk
authors.forename: Peter
authors.initials: P
authors.lastname: Brown
authors.forename: Colin
authors.initials: C
authors.lastname: Garner
authors.forename: Richard
authors.initials: R
authors.lastname: Glass
authors.forename: Chris
authors.initials: C
authors.lastname: Ridgway
authors.forename: Andy
authors.initials: A
authors.lastname: Hart
mesh_terms: D000818:Animals; D000835:Animals, Wild; D001717:Birds; D004032:Diet; D004781:Environmental Exposure; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D008322:Mammals; D013058:Mass Spectrometry / Q000379:methods*; D010573:Pesticide Residues / Q000032:analysis*; D012639:Seeds / Q000737:chemistry
chemical_list: D010573:Pesticide Residues