Persistence, dissipation and health risk assessment of combi-product profenofos and cypermethrin in/on sapota under sub-tropical agro-climatic conditions in India

Abstract

Sapota, a prominent and economically important fruit crop of India is susceptible to several species of insect and mite pests. Several pesticides formulations are used to control the pest damage in sapota. The present investigation was aimed to study the dissipation and persistence behaviour of combi-product profenofos 40% + cypermethrin 4% (44EC) at the standard dose (SD) (1162 g a.i. ha-1+106 g a.i. ha-1) and double to standard dose (2×SD) (2324 g a.i. ha-1+212 g a.i. ha-1) in/on sapota under tropical agro-climatic conditions of South Gujarat in India. Prior to quantitative analysis of pesticide residue on Gas chromatography with electron captured detector (GC-ECD), the modified Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) based method was validated on its accuracy, precision, linearity and sensitivity. Profenofos persisted in sapota up to 30 days with the half-lives of 5.65 and 7.34 days at SD and 2×SD, respectively. Cypermethrin dissipated at a rapid pace and was below quantitation limit (BQL) on 7 days at either dose of application; the half-life values recorded were 3.27 and 4.43 days at SD and 2×SD, respectively. This is the first case study that reflects 14 days as a waiting period after the last spray of combi-product (44EC) at standard dose facilitates the residue-free sapota fruits. Further, the health risk index (HRI<1) and Health Index (HI %< 100%) indicates that the application of combi-product profenofos 40% + cypermethrin 4% (44EC) at standard dose could not pose any health risk to Indian consumers.

Keywords

• cypermethrin
• dissipation
• health risk assessment
• profenofos
• sapota