Analytical method and risk assessment of pesticide in imported flowers

A pretreatment method for residual pesticides in cut flower was developed. The pH of The extract，the extraction solvent and the cleanup method were evaluated. the investigated pesticides includedtwo fungicides, chlorothalonil and hexaconazole, and six insecticides, carbaryl, cypermethrinfenitrothion,fenvalerate and malathion.最satisfactory recoveries obtained using acetonitrile as Theextraction solvent and InertSep GC/PSA for the cleanup step at pH 5.0 in these conditions. theoverall recoveries were 75-126% and the relative standard deviations ranged from 2.1 to 16%. This方法successfully applied to cut flower.Moreover，the volatilization of the indoor diffusion of spiked pesticides on the cut flower was evaluated. the volatilization of thespiked pesticides was confirmed with chlorothalonil, Hexaconazole，fenitrothion and malathion. The emission factor of fenitrothion was 0.10μg/(unit / h)，这是在chlorothalonil higher than those of chlorothalonil Hexaconazole and malathion. The calculated inhalationexposure for fenitrothion from a cut flower(0.0082μg/kg·day) was 1/900 of the acceptable dailyairway exposure level for fenitrothion(7.4μg/kg / day). Therefore，the effect of fenitrothion to human by emission factor appears to be low in daily life。

A pretreatment method for residual pesticides in cut flower was developed. The pH of the extract, the extraction solvent and the cleanup method were evaluated. The investigated pesticides included two fungicides, chlorothalonil and hexaconazole, and six insecticides, carbaryl, cypermethrin, fenitrothion, fenvalerate and malathion. The most satisfactory recoveries were obtained using acetonitrile as the extraction solvent and InertSep GC/PSA for the cleanup step at pH 5.0 in these conditions. The overall recoveries were 75-126% and the relative standard deviations ranged from 2.1 to 16%. This method successfully applied to cut flower.Moreover, the indoor diffusion of spiked pesticides on the cut flower was evaluated. The volatilization of the spiked pesticides was confirmed with chlorothalonil, Hexaconazole, fenitrothion and malathion. The emission factor of fenitrothion was 0.10μg/(unit・h), which is higher than those of chlorothalonil Hexaconazole and malathion. The calculated inhalation exposure for fenitrothion from a cut flower(0.0082μg/kg・day) was 1/900 of the acceptable daily airway exposure level for fenitrothion(7.4μg/kg・day). Therefore, the effect of fenitrothion to human by emission factor appears to be low in daily life.