GC/MSおよびLC/MS/MSを用いた牛乳中の残留農薬・動物用医薬品分析法

摘要

A simple, sensitive and selective method with gas chromatography/mass spectrometry (GC/ MS) and liquid chromatography/tandem mass spectrometry (LC/MS/MS) has been developed to detect 342 pesticides and veterinary drugs contaminating bovine milk at the maximum residue limits (MRLs) denned in the "positive list system". Sample preparation was performed by extracting the analytes with acetonitrile, followed by salting-out with sodium chloride. For some pesticides, the extract was further cleaned up by n-hexane partitioning and PSA cartridge column chromatography. GC/MS-EI or -NCI was used to determine pesticide residues, while LC/MS/ MS-ESI was applicable to the determination of pesticide and veterinary drug residues. The variation of the recoveries of these drugs at MRL was relatively wide; however the relative standard deviations of the recovery of each drug were within 28%, suggesting that the present method is good enough for use as a screening test for contaminants at the MRLs. These results show that this method is useful for multiresidue analysis of numerous pesticides and veterinary drugs in bovine milk.%平成18年5月29日に施行された食品中の残留農薬等rnに関するポジティブリスト制度では，乳における規制対象rn品目が農薬・動物用医薬品合わせて施行前の約30品目かrnら約800へと飛躍的に増加した．そのような状況のなか，rn乳の安全性を確保するためには生産段階における農薬などrnの使用・管理が非常に重要になってくるが，それを科学的rnに検証するためには多成分に対応した一斉分析法が有効なrn一つの手段となる．