Simultaneous multi-residue analytical method for anesthetics and sedatives in seafood samples by LC-ESI/MSMS.

A simultaneous multi-residue analytical method for 27 regulated and unregulated anesthetics and sedatives in seafood using liquid chromatography/tandem mass spectrometry with electrospray ionization (LC-ESI/MSMS) was developed and tested on flatfish, eels, and shrimp. To optimize the efficiency of the method, extraction and clean-up procedures with various solvents and sorbents were tested. The most efficient pretreatment methods were extraction using acetonitrile (ACN) only (for flatfish and eel) and 0.1 % ammonium acetate in ACN (for shrimp). Validation was performed under the guidelines of CODEX Alimentarius (CAC/GL-71) and the Korean National Institute of Food and Drug Safety Evaluation (NIFDS). The limit of detection (LOD), limit of quantification (LOQ), accuracy, and precision for all compounds ranged from 0.0002 to 0.002 mg/kg, 0.0005-0.005 mg/kg, 64.7-112.5 %, and 1.0-8.6 %, respectively. The coefficient of determination (linearity, R2) was over 0.98. Therefore, the method meets the requirements of both the domestic and international guidelines.

Residue Monitoring and Risk Assessment of Cyazofamid and Its Metabolite in Korean Cabbage Under Greenhouse Conditions.

The residual characteristics and risk assessment with respect to cyazofamid and its metabolite 4-chloro-5-p-tolylimidazole-2-carbonitrile were monitored in case of Korean cabbage at different preharvest intervals during a greenhouse trial. The 0.02 kg a.i/ha of cyazofamid was sprayed twice on seven-day intervals (i.e., on day 0, 7, 14, and 21 before harvest). The liquid chromatography-tandem mass spectrometry analysis was used to monitor the residual amount of fungicide. The matrix-matched calibration curves with respect to the cyazofamid in Korean cabbage exhibited good linearity (R2 ≥ 0.999) and acceptable recoveries of 84.1%-114.9%. The biological half-life of cyazofamid in Korean cabbage was 3.18 days. During the treatment, the preharvest residue of cyazofamid in Korean cabbage 14 days before harvest (0.80 mg/kg) was lower than that specified by the MFDS-MRL (Ministry of Food and Drug Safety-Maximum Residue Limit, 2.0 mg/kg) and should be recommended as the safe preharvest-interval application limit. The hazard quotient showed low toxicity (70.58%) during the risk assessment study of cyazofamid.