Fate and cumulative risk assessment of typical pesticides in celery cultivated in summer cool open fields

This study evaluated residue dynamics, dissipation kinetics, and cumulative dietary risk of typical pesticides (imidacloprid, acetamiprid, thiamethoxam, pymetrozine, difenoconazole) on celery in summer cool-climate open fields, alongside compatibility of current pesticide registration labels. Following two-year field trials, pesticides exhibited first-order dissipation with half-lives of 0.85-4.01 days and final residues of 0.0015-13 mg/kg. Individual dietary risks were summatized below: long-term risk quotients represented 8-174 % of acceptable daily intake; short-term intakes were 1-11 % of acute reference dose. The hazard index (HI) and point of departure index (PODI) methodologies for cumulative risk assessment produced chronic values of 0.3381 and 0.3464, and acute values of 0.1412 and 0.1397, respectively. While all values fell below risk thresholds, elevated residues of difenoconazole were associated with a chronic risk. Registration labels demonstrated good environmental compatibility except for difenoconazole. This research provides critical data for refining residue management and promoting sustainable celery production in cool-climate regions.