Residues determination, risk assessment, half-life and dissipation behaviour of flusilazole formulation

Abstract To determine the risk assessment, half‑life and waiting period of flusilazole on apple fruit (Malus Domestica Borkh.) under temperate conditions of Kashmir, India, Flusilazole 40 EC was applied on Red Velox apple trees two months prior to harvest at 80 g a.i. ha-1 (recommended) and 160 g a.i. ha-1. The analytical samples of flusilazole were analysed by high-performance liquid chromatography (HPLC) through a reverse phase. Recovery percentage of flusilazole at three fortification levels (0.5, 1.0 & 1.5 ppm) were found to be 110.70, 97.33 and 103.16%, respectively. Flusilazole at the recommended dose (80 g a.i. ha-1) left an initial deposit of 0.733 ppm which dissipated by 93.45% in 60 days and was non-detectable beyond this period. While flusilazole at double the recommended dose (160 g a.i. ha-1) left an initial deposit of 0.913 ppm which dissipated by 93.43% in 70 days and was non-detectable beyond this period. Based on the maximum residue limit of 0.3 ppm as prescribed by the Codex Alimentarius Commission, a waiting period of 28.74 days and 46.03 days were recorded for single and double doses, respectively. Moreover, in order to assess the consumer risk, theoretical maximum residue contributions (TMRC) were derived using flusilazole residues (average and maximum) recorded at various time intervals and compared to the maximum permissible intake (MPI) and consequently an acceptable daily intake (ADI) of 0.001 mg kg-1 body weight/day can be recommended. The MPI was determined by multiplying the recommended ADI with the average person's weight (60 kg) and was found to be 0.006 mg person-1 day-1. Based on the average per capita daily consumption of 6.76 g apple in India, the TMRC values were found to be (0.0049 and 0.00534 mg day-1 person-1) and (0.0061 and 0.0062 mg day-1 person-1) for average and maximum flusilazole residues at single and double dose, respectively. The TMRC values were far less than MPI at both doses of application at 0 day; therefore, the consumer health risks are minimal even at double the recommended dosage.