The Analysis And Study Of Several Pesticides Residuse In Apple

In this paper, we research the method of determination residues of fenpropathrin, cyhalothrin, chlopyrifos and parathion in apple. At the same time, we research their degradation trend in apple, and the influence to pesticide residues by spraying different concentration and times, and the mainly residues position of pesticide in apple. The result of fallowing: 1. We adopt acetonitrile as extraction solvents in preparation. The extraction solution has little impurity and comparatively cleaner. Organophosphorus pesticide extraction solution needn't to be purify, organochlorine pesticide extraction solution only need to be clean-up by florisil layer analysis columniation. The step of preparation was simplified, and the method reduced solvent consumption, saving time, and has the better rate of recovery rate and coefficient of variation, it can achieve the request of the residues of pesticides determination. 2. Through the test of degradation trend of four kinds of pesticide ,we obtain the degradation equation of double concentration uses one time in apple: The degradation equation of fenpropathrin is C=0.3626·e(-0.0342t)(r=0.9633), and the residues half life (T1/2 ) is 20.3d; The degradation equation of cyhalothrinis C=0.3626·e^-0.0342t(r=0.9633),and the residues half life (T1/2 ) is 11.2d The degradation equation of chlopyrifos C=0.3626·e^-0.0342t(r=0.9633), and the residues half life (T1/2 ) is 3.1d; The degradation equation of parathion C=0.3626·e^-0.0342t(r=0.9633), and the residues half life (T1/2 ) is 7.7d. 3. After spray pesticide fenpropathrin, cyhalothrin, chlopyrifos and parathion in apple, the residues was influence mainly by the uses concentration, and less by uses times. But different uses concentration and uses times of chlopyrifos and parathion has less influence to residues half life, and their residues half life is nearly respectively. 4. After spray pesticide, the residue order of fenpropathrin, cyhalothrin, chlopyrifos and parathion in different position of apple is: peel >apple> pulp, and the residue in peel position is far over than pulp , pesticide main remain in peel position of apple, the pulp position remains relatively low. So after spray fenpropathrin, cyhalothrin, chlopyrifos and parathion in apple, residue of peel position is the key factor which it is appraise to residues could accord with or not accord with maximal residues limit standard. At the same time, it is the key factor to instruct pesticide application in apple safety producing too.