Residue pattern of fenitrothion in grapes

• Author(s): Choi, Hoon; Hong, Yong-Soon; Kim, Jeong-Han; Lee, Kyu-Seung; Lee, Youn-Hyung; Liu, Kwang-Hyeon; Moon, Joon-Kwan; Park, Hee-Won;
• Abstract: The residue patterns of an insecticide, O,O-dimethyl O-4-nitro-m-tolyl phosphorothioate (fenitrothion) used for grapes were investigated during cultivation and storage. Initial residue concentrations of fenitrothion in grapes at a standard application rate was 0.50 mgcntdotkg-1 and decreased to 0.10 mgcntdotkg-1 after 10 days with a half life of 4.8 days. At double rate application, initial concentration was 1.00 mgcntdotkg-1 and decreased to 0.24 mgcntdotkg-1 after the same period with a half life of 4.9 days. Maximum residue limits during cultivation were suggested by prediction curve derived from the decay equation of fenitrothion at double rate treatment. For example, 2.03 mgcntdotkg-1 was calculated for 10 days before harvest and 1.01 mgcntdotkg-1 for 5 days. While no significant degradation was observed during the storage at low temperature, typical degradation pattern was identified at room temperature. Half lives of fenitrothion of 0 days after treatment (DAT) samples were 3.2 days for standard rate, and 6.2 days for double rate. Samples of 5 DAT gave 2.1 days of half life for standard rates, and 5.7 days for double rate. Fenitrothion was washed out by 54.7-69.7% with tap water, 54.7-81.6% with 0.2% detergent solution, and 71.2-86.9% with 0.1% detergent solution.
• Publication Date: Aug 2003
• Journal: Journal Of The Korean Society For Horticultural Science