Terminal residues, dissipation dynamics and dietary risk assessment of metalaxyl-M in four types of food

Abstract

Metalaxyl-M has become a widespread fungicide utilized across a diverse array of crops, posing potential food residue and human safety concerns. Given limited research into terminal residues, dissipation dynamics and dietary risk assessment of metalaxyl-M, the research aims to investigate the fate of metalaxyl-M, on four key crops: potatoes, taroes, melons, and grapes employing ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). In this study, the residues and dietary risk assessment of metalaxyl-M was assessed by evaluating the fate of metalaxyl plus metalaxyl-hydroxymethyl, which was defined as total metalaxyl. Results revealed the dissipation half-life of total metalaxyl on grapes was in the range of 10.7–14.2 days, while non-first-order kinetics were observed in other crops. Final residues of total metalaxyl consistently remained below MRLs across all crops. Risk quotients for total metalaxyl were significantly below 100 % on all crops, indicating a minimal health risk to Chinese adults. The findings of this study provide a comprehensive understanding of total metalaxyl residues, the dissipation, and the dietary risk, providing valuable insights for metalaxyl-M application.