Residue content of carbaryl applied on greenhouse cucumbers and its reduction by duration of a pre‐harvest interval and post‐harvest household processing

Abstract

Carbaryl is widely used to control various insect pests on greenhouse cucumbers in Iran. Therefore the control of residual levels of this insecticide is highly necessary. The effects of the household processing such as washing, peeling and refrigeration storage, at 4 °C for 2 days on the reduction of residue levels in the plant tissues were investigated in the different groups. Samples were collected at 1 h to 14 days after application and analysed to determine the content and dissipation rate of carbaryl. Analysis was carried out by the QuEChERS method using HPLC-UV. Carbaryl residue in samples, which were collected post-application in different times showed a gradual and significant (P < 0.05) decrease. The half-life (t(1/2)) of carbaryl applied on cucumbers was 3.2 days. Carbaryl residues were detected in concentration ranges of 0.22-4.91 mg kg(-1). Also, the results indicated that the consumable safety time of carbaryl was found to be more than 14 days on cucumber. Household processing, such as washing and peeling and refrigeration storage, was effective in reducing the residue levels. Also, peeling was the most effective way to reduce the carbaryl residues of the cucumber samples. Washing and refrigerated storage also decreased carbaryl residues.