Dissipation kinetics and effect of different decontamination techniques on the residues of emamectin benzoate and spinosad in cowpea pods

Abstract

Dissipation and decontamination of the semisynthetic macrolide emamectin benzoate and the natural insecticide spinosad on cowpea pods were studied following field application at single and double doses of 11.0 and 22 and 73 and 146 g ai ha(-1), respectively. Residues of these naturalytes were estimated using LC-MS/MS. The initial deposit of 0.073 and 0.153 mg kg(-1) of emamectin benzoate dissipated below quantitation level on the fifth and seventh day at single and double dosage, respectively. For spinosad, the initial deposits of 0.94 and 1.90 mg kg(-1) reached below quantitation level on the 7th day and 15th day at single and double dosage, respectively. The half-life of emamectin benzoate and spinosad was 1.13-1.49 and 1.05-1.39 days with the calculated safe waiting period of 2.99-6.12 and 1.09-3.25 days, respectively, for single and double dosage. Processing of the harvestable pods with different decontamination techniques resulted in 33.82 to 100 % removal 2 h after the application of emamectin benzoate and 100 % removal 3 days after spraying, while the removal was 42.05 to 87.46 % 2 h after the application of spinosad and 38.05 to 68.08 % 3 days after application.

Perspective Chapter: Current Situation of Insecticide Residues in Food Commodities and Possible Strategies for Management of Residues

“…When dipped in the solution, neonicotinoids with high water solubility were easily separated from the fruits in salt media. Vijayasree et al [25] discovered that tamarind water (2%) and salt chloride (2%) solutions eliminated 85.56 and 100% of the emamectin benzoate in cowpea pods, respectively. Buprofezin residues in oranges were reduced by 36.50 and 27.51%, respectively, after washing with tap water and salt chloride solution (2%) [26].…”

Dissipation Dynamic, Residue Distribution and Risk Assessment of Emamectin Benzoate in Longan by High-Performance Liquid Chromatography with Fluorescence Detection

“…As far as we know, some studies have analyzed the emamectin benzoate residue in agricultural products, such as rice [16], okra [17], tomato [18], vegetables [19,20], cotton [21], tea [22], and tobacco [23]. There are few reports about the dissipation and residue of emamectin benzoate in apple [24], cabbage [25,26], cowpea pods [27], and paddy [28]. The instruments used in the above methods included HPLC-FLD, HPLC, and HPLC-MS/MS.…”

Development and validation of integrated pest management modules against spotted pod borer Maruca vitrata Fabricius on garden bean Lablab purpureus var. typicus (L.)

“…Vijayasree et al (2014) reported a safe waiting period of 2.99 and 6.12 days when emamectin benzoate was Economics of IPM module for management of M.vitrata in garden bean…”