Laboratory Calibration and Field Deployment of the Polar Organic Chemical Integrative Sampler (POCIS) for Pharmaceuticals and Personal Care Products
Sampling rates for 25 different pharmaceuticals and personal care products (PPCPs) were determined on the passive commercially available Polar Organic Chemical Integrative Sampler (POCIS). Passive sampling devices such as the POCIS can capture time-weighted average (TWA) water concentrations of water-soluble organic pollutants. To date, calibration of POCIS sampling rates has only been carried out for a limited list of compounds, mainly pesticides. In this work, laboratory calibration experiments were conducted under flowing and quiescent water conditions. Uptake rates were 0.040 L/d to 2.462 L/d under flowing conditions while quiescent conditions resulted in uptake rates between 0.016 L/d and 0.223 L/d. The uptake of many PPCPs appears to be controlled by the effective thickness of the stagnant aqueous boundary layer at the sampler surface. This is indicated by sampling rates that are higher in flowing conditions. The controlling factor for some PPCPs still remains unclear. Sampling rates correlated with physical-chemical properties such as octanol-water partition coefficients. Field deployments of several weeks, accompanied by regular grab-samples, were carried out in wastewater and surface water. The field study demonstrated that the POCIS, when coupled with laboratory derived uptake rates herein, can be used to generate accurate TWA concentrations of PPCPs in the aquatic environment.