Degradation of Imidacloprid and Acetamiprid Residues in French Beans during Household Processing

In order to estimate human exposure to pesticides from processed food, herein we employed high-performance liquid chromatography to investigate the effects of household processing on the content of acetamiprid and imidacloprid residues in French beans. The results showed that the pesticide residues decreased during cooking with degradation rates of 49%-57% during frying, 22%-32% during steaming, 81%-91% during boiling in an open pan, and 77%-85% during boiling in a closed pan. The residue levels in the soup obtained by boiling the French beans with water for 10 min in a covered pan ranged from 0.07 to 0.08 mg/L. Moreover, after stir-frying, the two kinds of pesticides degraded by 35%-38%, while microwave heating for 2 min led to 26%-36% degradation of the pesticides in the French beans. The results confirmed that cooking method, temperature, time, melting point of pesticides, vapor pressure and solubility in water all affected the final residues of acetamiprid and imidacloprid in food.