Journal of Food Safety and Quality

Objective To evaluate the residual levels of tolfenpyrad and diafenthiuron in Brassica oleracea and assess the chronic dietary intake risk. Methods Brassica oleracea samples sprayed with 30% diafenthiuron·tolfenpyrad suspension concentrate were collected. The pesticide residues were detected using dispersive solid phase extraction coupled with ultra performance liquid chromatography-triple quadrupole tandem mass spectrometry. Based on the detection results, the chronic dietary intake risk was calculated using a risk probability formula, and a safety assessment was conducted. Results When 30% diafenthiuron·tolfenpyrad suspension concentrate was applied once at the maximum recommended dose of 180 g a.i./hm2 with a 7-day pre-harvest interval, the residual concentrations of tolfenpyrad and diafenthiuron in Brassica oleracea were <0.01–0.39 mg/kg and 0.03–0.12 mg/kg, respectively. Both pesticide residues were below China’s maximum residue limits (MRLs) (0.5 mg/kg for tolfenpyrad and 2.0 mg/kg for diafenthiuron). Based on China’s pesticide registration and usage data, the national estimated daily intake of tolfenpyrad and diafenthiuron for the general population was 0.2215 mg and 0.0967 mg, respectively, with risk quotient of 58.6% and 51.2%, both below 100%. This indicated that the dietary intake risk was within an acceptable range. Conclusion When 30% diafenthiuron·tolfenpyrad suspension concentrate is applied at the recommended dose with a 7-day pre-harvest interval for controlling Plutella xylostella in Brassica oleracea, the pesticide residues in harvested Brassica oleracea comply with food safety standards. The long-term dietary intake risk for the general population is controllable, ensuring safe consumption.

Brassica oleracea; tolfenpyrad; diafenthiuron; ultra performance liquid chromatography-triple quadrupole tandem mass spectrometry; dietary risk