Calibration and field application of an innovative passive sampler for monitoring groundwater quality

This study describes the development of a novel Empore™ disk-based passive sampler specially adapted to groundwater monitoring. The sampler was calibrated in the laboratory using conditions that corresponded to groundwater (i.e. matrix medium, water temperature, flow rate and water flow across the disks). The retention and elution performance for sixteen semi-polar and polar pollutants on the Empore™ disk (47 mm diameter, SDB-XC) was evaluated. Recoveries were ~80% for the majority of compounds. Sampler uptake kinetics were measured over fourteen days at three concentrations (10, 100 and 500 ng L^-1) and the sampling rate (R_S) calculated for four compounds. There was no influence of concentration of the test analyte on the uptake profile; with mean R_S varying between 0.018 ± 0.007 L day^-1 and 0.047 ± 0.001 L day^-1. Passive samplers were deployed in twelve characterized groundwater wells near Lyon (France). Atrazine, atrazine-desethyl and diuron were the main pollutants found with a maximum time-weighted concentration of 61 ± 3, 62 ± 24 and 127 ± 49 ng L^-1 respectively.