LAUSR

Neonicotinoid pesticides are highly hydrophilic systemic insecticides that have been extensively used worldwide. To evaluate their environmental risks, the concentrations of these pesticides in the aquatic environment must be monitored. While Polar Organic Chemical Integrative Sampler (POCIS) has been proven to be a suitable passive sampler for many highly hydrophilic compounds, HLB POCIS showed limitations such as short linear uptake ranges in the monitoring of neonicotinoid pesticides. Here, POCIS was optimized for neonicotinoid pesticides by selecting a suitable adsorbent and filter. The ENVI-Carb nonporous carbon-based adsorbent demonstrated a good balance between strong sorption and high recovery. Static renewal experiments showed that the new POCIS device using ENVI-Carb with a polyethersulfone (PES) membrane filter had a 3 d (dinotefuran) to 28 d (clothianidin, imidacloprid, acetamiprid, and thiacloprid) linear range, which is longer than that of HLB POCIS (≤ 1 (dinotefuran) to 14 d). The POCIS using ENVI-carb with a polytetrafluoroethylene membrane had higher sampling rates (0.270 (clothianidin) to 0.686 (imidacloprid) L/d) than those of the HLB POCIS for short-term deployment. The time-weighted average concentrations in actual river water measured by the new POCIS were in good agreement with those obtained by repeated grab sampling, within 30 %. Moreover, POCIS detected two neonicotinoid pesticides that were not detected by grab sampling. Thus, the proposed POCIS is a promising tool for the monitoring of neonicotinoid pesticides. This article is protected by copyright. All rights reserved.