Dissipation of sixteen pesticide residues from various applications of commercial formulations on strawberry and their risk assessment under greenhouse conditions

Twelve commercial pesticide formulations containing sixteen active ingredients were applied on greenhouse strawberries at recommended and double doses. The dynamics and dietary risk analysis were investigated. A modified QuEChERS method based on the use of multi-walled carbon nanotubes (MWCNTs) as adsorbent followed by LC-MS/MS and GC-MS/MS detection was utilized for sample analysis. The half-lives of studied pesticides were 4.6-12.6 days and 3.8-15.8 days from two application doses. Dietary levels from the residue concentrations of the individual pesticides at harvest was contrasted with the acceptable daily intake (ADI) and acute reference dose (ARfD). The dietary risk assessment adopt the risk quotient (RQ) for chronic risk and risk probability (RP) for long-term dietary intake risk, respectively. The dietary risk induced by the studied pesticide residues in strawberry was acceptable for consumers except the pesticide fumigants. The pesticide residues at different pre-harvest intervals (PHIS) under greenhouse conditions were compared with the established maximum residue limits (MRLs). To reduce the residue levels and potential safety risk, a longer PHI or reduced application rates should be conducted.