Residue and dissipation of two formulations of emamectin benzoate in tender cowpea and old cowpea and a risk assessment of dietary intake

• Published in: Food chemistry Vol. 361; p. 130043
• Main Authors: Wang, Ruifei, Liu, Benju, Zheng, Qun, Qin, Deqiang, Luo, Peiru, Zhao, Weihua, Ye, Cuiyi, Huang, Suqing, Cheng, Dongmei, Zhang, Zhixiang
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.11.2021
• Subjects: Cowpea; Dissipation; Emamectin benzoate; Formulation; Pod periods; Residue; Cowpea; Pod periods; Residue; Formulation; Dissipation; Emamectin benzoate
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2021.130043

•Dissipation and terminal residues of emamectin benzoate EC and ME in cowpea were studied.•The dietary intake risk of emamectin benzoate in tender cowpea and old cowpea was evaluated.•Half-lives of emamectin benzoate EC and ME in tender cowpea and old cowpea are less than 3 d.•Terminal residues in tender cowpea and old cowpea are lower than the MRLs issued by China after 7 d. The dissipation and residue levels of emamectin benzoate emulsifiable concentrate (EC) and microemulsion (ME) formulations in tender cowpeas and old cowpeas were investigated under field conditions. The decline curves of emamectin benzoate residues in cowpea corresponded to first-order kinetics. The dissipation rate of emamectin benzoate in tender cowpeas was faster than that in old cowpeas. The half-lives of the EC were 1.34–1.39 d and 1.74–2.31 d in tender cowpea and old cowpea, respectively. For the ME, the half-lives were 1.39–1.51 d and 2.08–2.67 d, respectively. The risk of adult intake of emamectin benzoate from cowpea is within the acceptable limits of the human body. Compared to tender cowpeas, the risk of eating old cowpeas is higher. Emamectin benzoate (EC) is recommended for cowpeas when the intention is to harvest tender cowpeas, while both formulations are acceptable for cowpeas when the intention is to harvest old cowpeas.