Residues and dietary risk assessment of beta-cyfluthrin and clothianidin in cabbage under Chinese cultivation conditions

Abstract

The novel formulation, 42% beta-cyfluthrin • clothianidin suspension concentrate, is preparing for registration to control Phyllotreta striolata in cabbage fields in China, but the residue and dietary risk of beta-cyfluthrin and clothianidin in cabbage is still unclear. Here, the residual levels of beta-cyfluthrin and clothianidin in cabbage were detected by a modified QuEChERS method coupled with high-performance liquid chromatography-tandem mass spectrometry. The average recoveries of the two insecticides ranged from 79.6% to 104.4%, with relative standard deviations ≤ 11.2%. The limits of quantification for both compounds were 0.01 mg/kg. The field trials were carried out at twelve presentative provinces in China, and the formulation was sprayed twice with a spraying interval of 10 days on cabbage at a dose of 94.5 g a.i./ha. At the preharvest interval of 7 days, the terminal residues of beta-cyfluthrin and clothianidin in cabbage were below 0.388 mg/kg and 0.298 mg/kg, respectively, which were lower than their maximum residue limits in China. The chronic and acute risk quotient of beta-cyfluthrin and clothianidin for different Chinese consumers ranged from 0.031% to 65.0%, indicating an acceptable dietary risk. Under Good Agricultural Practices, the novel formulation is safe to apply in cabbage fields in China.