LC-MS/MSを用いた農産物中残留農薬の迅速試験法に関する検討

摘要

Rapid multi-residue analysis of pesticides in agricultural products was studied by using LC-MS/MS. Pesticide residues in10 g of homogenized agricultural products were extracted with 30 mL of acetonitrile and salted out with 4 g of anhydrous magnesium sulfate and1g of sodium chloride in the presence of citrate salts for buffering in a disposable tube. Co-extractives were removed by use of our original triple layered column (C18/GC/PSA; 60/30/60 mg). According to the method validation guideline of the Ministry of Health, Labour and Welfare of Japan, we conducted recovery tests in 5 kinds of agricultural products (brown rice, kiwi, cabbage, sweet potato and spinach) spiked with 60 pesticides at the level of 0.01 or 0.1 μg/g. Each concentration of pesticide spiked was extracted from 2 samples per day on 5 days. Pesticides in the test solution were determined by two types of LC-MS/MS using scheduled MRM. Using this method, 58 out of 60 pesticides satisfied the guideline criteria in brown rice, 59 in kiwi, 55 in cabbage, 55 in sweet potato and 56 in spinach. This method is applicable for routine examination of pesticide residues in agricultural products.%LC-MS/MSを用いた農産物中残留農薬の迅速試験法について検討した.試料10gに，アセトニトリル30mLを加えホモジナイズ後，無水硫酸マグネシウム4g，塩化ナトリウム1gおよびクェン酸緩衝剤を加えて農薬を抽出した.また，夾雑成分を除去するため，独自の3層固相カラム（C18/GC/PSA;60/30/60mg）を使用した.また試験液の測定は，2台のLC-MS/MSを組み合わせ，スケジユールドMRMモードで実施した.厚生労働省通知の妥当性評価ガイドラインに従って，5種の農産物（玄米，キウィー，キャベツ，かんしょ，ほうれんそう）における，本法の妥当性評価を行った.結果，60農薬中，ガイドラインによる評価基準を満たしたものは.玄米で58,キウィーで59,キャベツで55,さつまいもで55,ほうれんそうで56農薬であった.本法は，農産物中残留農薬の日常検査に有用であることを確認した.