Effective abatement of 29 pesticides in full-scale advanced treatment processes of drinking water: From concentration to human exposure risk

Highlights: • Advanced treatment processes could effectively abate multiple pesticides. • Low ambient temperatures weakened the removal of pesticides in the BAC process. • The EDI level of target pesticides in the finished water could be reduced by 67%. • EDI levels of all pesticides were much lower than ADI levels. This study investigated the occurrence and removal of 29 pesticides in 4 drinking water treatment plants (DWTPs) with conventional and advanced treatment processes (i.e., ozonation + biological activated carbon, and ultrafiltration) in Shanghai, China from 2018 to 2019. The concentration levels of target pesticides in raw waters ranged from below the limit of quantification (−1, whereas in finished waters significantly decreased to a range of −1. The application of the advanced treatment process could effectively remove target pesticides. For example, the highest removal of isocarbophos after the advanced treatment process reached 94.6%, whereas its removal after the conventional treatment process was just 42.6%. The estimated daily intake level of target pesticides in finished water, which were pretty lower than acceptable daily intake levels in finished water, could be reduced by 67% if combining the conventional and advanced treatment processes. Although the multiple pesticides in raw waters were effectively removed by advanced treatment process, their synergistic toxic effects induced by the residual pesticides and their degradation by-products on human health deserve further attentions.