Performance of the Chemcatcher® passive sampler when used to monitor 10 polar and semi-polar pesticides in 16 Central European streams, and comparison with two other sampling methods

We investigated the performance of the Chemcatcher®, an aquatic passive sampling device consisting of a sampler body and an Empore® disk as receiving phase, when used to monitor acetochlor, alachlor, carbofuran, chlorfenvinphos, α-endosulfan, fenpropidin, linuron, oxadiazon, pirimicarb and tebuconazole in 16 Central European streams. The Chemcatcher®, equipped with an SDB-XC Empore® disk, detected seven of the aforementioned pesticides with a total of 54 detections. The time-weighted average (TWA) concentrations reached up to 1 μg/L for acetochlor and alachlor. Toxic units derived from these concentrations explained reasonably well the observed ecological effects of pesticide stress, measured with the SPEAR index. In a follow-up analysis, we compared the Chemcatcher® performance with those of two other sampling systems. The results obtained with the Chemcatcher® closely matched those of the event-driven water sampler. By contrast, the TWA concentrations were not significantly correlated with concentrations on suspended particles. We conclude that the Chemcatcher® is suitable for the monitoring of polar organic toxicants and presents an alternative to conventional spot sampling in the monitoring of episodically occurring pollutants.