Nationwide monitoring and human health risk assessment of pesticides in edible shellfish species across coastal areas of South Korea.

Although pesticides continuously discharged into the water environment after use are a concern in fishery products, their management is insufficient due to a lack of regulations. Especially, investigations for other species, including shellfish, are more limited because the regulations mostly focus on fish. This study investigated the presence of 54 pesticides comprising organochlorine pesticides (OCPs), insecticides, herbicides, and fungicides in edible shellfish across 108 coastal sites. Pesticides were analyzed using a liquid chromatography-tandem mass spectrometry and a gas chromatography-tandem mass spectrometry after a quick, easy, cheap, effective, rugged, and safe pretreatment. OCPs (except for not detected; 0.152-5.27 μg/kg; mean 0.741 μg/kg; median 0.439 μg/kg) with a detection frequency of 17.9 % showed lower total concentrations than non-OCPs (0.0728-63.6 μg/kg; mean 2.31 μg/kg; median 1.11 μg/kg) with a detection frequency of 54.1 %. Among 31 pesticides detected in shellfish, deltamethrin (0.235-13.0 μg/kg; mean 1.23 μg/kg; median 1.09 μg/kg), azoxystrobin (0.0831-4.44 μg/kg; mean 0.477 μg/kg; median 0.255 μg/kg), p,p'-dichlorodiphenyldichloroethylene (0.152-0.795 μg/kg; mean 0.329 μg/kg; median 0.288 μg/kg), diuron (0.0681-41.5 μg/kg; mean 1.66 μg/kg; median 0.144 μg/kg), and diphenylamine (0.307-7.48 μg/kg; mean 1.87 μg/kg; median 1.21 μg/kg) had detection frequencies higher than 10 %. Pesticides showed no significant differences in concentrations according to the sampling periods, regions, or shellfish species. In the human health risk assessment, the chronic and acute risk values were acceptable, indicating no appreciable concern to human health.