LC-MS/MSによる味付け海苔中のチアベンダゾールの分析法の検討

摘要

Thiabendazole (TBZ), a pesticide with antifungal activity, was detected in toasted and seasoned laver which had been reported as tasting unpleasant by consumers in March 2008. From a survey of the manufacturing process, it was concluded that the TBZ contamination had originated from a sponge-roller which was used to paste seasoned liquid onto the toasted laver. At that time it was found that TBZ is widely used to prevent fungal contamination of sponge-rollers. For further survey of TBZ contamination in the laver, we developed a more sensitive detection method using LC-MS/MS. With our new method, six commercial products harvested in March 2008 and July 2009, respectively, were tested. Five out of six samples harvested in 2008 were positive for TBZ, with values in the range from 0.014 to 1.736 μg/g. Only one sample harvested in 2009 contained a detectable level of TBZ. The data obtained here contributed to the improvement of the manufacturing process.%苦情検体の味付け海苔からチアベンダゾール（TBZ）がrn検出された事例を経験した．原因調査の結果，味付け工程rnで調味液を塗布する機械に使用されるスポンジロールに，rn抗菌目的で使用されていたTBZが海苔に移行したことがrn判明した．今回，LC-MS/MSを用いて味付け海苔中のrnTBZの定量法を検討した．味付け海苔の製造工程でこのrnスポンジロールが広く普及していたことから，改良した定rn量方法を用いて同時期と翌年の市販品についてTBZの調rn査を実施した．苦情事例のあった平成20年3月では6検rn体中5検体で0.014～1.736μg/g，翌年の平成21年7月rnでは6検体中1検体で微量のTBZが検出された．以上のrnことから味付け海苔の製造工程が見直され，現在では改善rnしていると考えられた．