BACKGROUND: Dithiocarbamte fungicides have been used in crop cultivation for diseases protection and treatment. And cultivated agricultrual products were used as feedstuff, and residual pesticides are likely to be absorbed and transferred to livestock. But the maxium residue limits (MRLs) were not established for dithiocarbate fungicides in livestock products, thus an analysis method was developed and validation for dithiocarbamate fungicides to establish MRLs.
METHODS AND RESULTS: Samples were prepared using CS2 trap method and detected with UV/VIS spectrophotometer. Calibaration line (0.1 ∼ 10 ㎍/mL) was linear with r2⟩0.99. For validation, the recovery tests were carried out at three fortification levels (MLOQ, 10 MLOQ and 50 MLOQ) from livestock samples (egg, milk, beef, pork and chicken). The results for mancozeb, propineb and thiram ranged between 76.8 to 109.6 %, 79.4 to 108.8 % and 80.2 to 107.8 %, respectively and %RSD (relative standard deviation) valuse were below 9.5%. Furthemore, inter-laboratory was performed to validate the method.
CONCLUSION: All values corresponded with the criteria ranges requested by both the CODEX (CAC/GL 40-1993, 2003) and MFDS guidelines (2016). It can be used as an official analytical method for determination of dithiocarbamate fungicides for established MRLs and monitoring.