Residue dissipation kinetics, safety evaluation and decontamination of hexaconazole in green chilli

Hexaconazole is one of the most popular fungicides used for the chemical control of several diseases in many vegetable crops, but its residues may remain in the crops and soil. Hence, the residue analysis of hexaconazole, its dissipation kinetics and food safety evaluations in green chilli and soil were undertaken for two seasons at Varanasi, India. Residues were extracted using ethyl acetate from chilli fruits and soil. Primary secondary amine (PSA), graphitised carbon black (GCB) and magnesium sulphate were used as cleaning agents for samples. The percent recovery at 0.01, 0.02, 0.05, 0.10 and 0.50 mg/kg was 86.33-94.67% in green chilli and 81.67-93.00% in the soil. The average matrix effect (ME) percentage was less than 9.00% for green chilli and less than 8.70% for the soil. The method optimised data in the present study satisfied the EU protocol for method validation and are considered appropriate for the determination of hexaconazole residue in matrices of green chilli fruits and soil. The study revealed that half-lives of hexaconazole in green chilli were 1.91 days and 3.47 days for recommended dose (RD) and double of the recommended dose (DD), respectively, for the year 2019, whereas in the year 2020, half-lives were 1.84 and 3.24 days for RD and DD, respectively. The terminal residue in the soil was estimated below the limit of quantification. The food safety assessment submits that the green chilli fruits could be considered safer for consumption after the projected pre-harvest intervals (PHIs). Different household processes were evaluated for removal of/minimising the incurred hexaconazole residue in green chilli. Washing with boiling water could be used as a most effective decontamination strategy for hexaconazole from green chilli.

Automated summary

This study investigated the residue analysis, dissipation kinetics, and food safety evaluations of Hexaconazole in green chilli and soil. The results showed that Hexaconazole had a short half-life in green chilli, and washing with boiling water was an effective decontamination strategy to remove the residue.