Persistence and risk assessment of spiromesifen on tomato in India: a multilocational study

Supervised field trials were conducted at four different agro-climatic locations of India to evaluate the dissipation pattern and risk assessment of spiromesifen on tomato. Spiromesifen 240 SC was sprayed on tomato at 150 and 300 g a.i. ha(-1). Samples of tomato fruits were drawn at 0, 1, 3, 5, 7, 10 and 15 days after treatment and soil at 15 days after treatment. Quantification of residues was done on gas chromatograph-mass spectrophotometer in selective ion monitoring mode in the mass range of 271-274 (m/z). The limit of quantification of the method was found to be 0.05 mg kg(-1), while the limit of determination was 0.015 mg kg(-1). Residues were found below the LOQ of 0.05 mg kg(-1) in 10 days at both the doses of application at all the locations. Spiromesifen dissipated with a half-life of 0.93-1.38 days at the recommended rate of application and 1.04-1.34 days at the double the rate of application. Residues of spiromesifen in soil were detectable level (<0.05 mg kg(-1)) after 15 days of treatment. A preharvest interval (PHI) of 1 day has been recommended on tomato on the basis of data generated under All India Network Project on Pesticide Residues. Spiromesifen 240 SC has been registered for its use on tomato by Central Insecticide Board and Registration Committee, Ministry of Agriculture, Government of India. The maximum residue limit (MRL) of spiromesifen on tomato has been fixed by Food Safety Standard Authority of India, Ministry of Health and Family Welfare, Government of India as 0.3 μg/g after its risk assessment.