water quality assessment; passive sampling; polar organic micropollutants; organic trace analytics; bioaccumulation; bioconcentration; water quality criteria; polar organic compounds
Vermeirssen Etiënne L M, Dietschweiler Conrad, Escher Beate Isabella, Van Der Voet Jürgen, Hollender Juliane (2013), Uptake and release kinetics of 22 polar organic chemicals in the Chemcatcher passive sampler, in Analytical and Bioanalytical Chemistry
, 405(15), 5225-5236.
Vermeirssen Etienne L.M., Dietschweiler Conrad, Escher Beate I., van der Voet Jürgen, Hollender Juliane (2012), Transfer kinetics of polar organic compounds over polyethersulfone membranes in the passive samplers POCIS and Chemcatcher, in Environmental Science and Technology
, 46, 6759-6766.
Vermeirssen Etiënne L M, Hollender Juliane, Bramaz Nadine, Van Der Voet Jürgen, Escher Beate Isabella (2010), Linking toxicity in algal and bacterial assays with chemical analysis in passive samplers deployed in 21 treated sewage effluents, in Environmental Toxicology and Chemistry
, 29(11), 2575-2582.
Vermeirssen Etiënne L M, Bramaz Nadine, Hollender Juliane, Singer Heinz P., Escher Beate Isabella (2009), Passive sampling combined with ecotoxicological and chemical analysis of pharmaceuticals and biocides - evaluation of three Chemcatcher™ configurations, in Water Research
, 43(4), 903-914.
Various organic micropollutants enter rivers and lakes and this undefined mixture and their associated metabolites are still increasing in diversity. The multitude of micropollutants leads to an undesired and problematic exposure situation for aquatic organisms. For these reasons, there are increasing efforts to set-up water quality standards for organic micropollutants, initially for persis-tent hydrophobic compounds but more recently also for polar organic compounds such as herbicides and pharmaceuticals. These developments in the area of water quality assessment require that appropriate sampling tools are available to support current and future monitoring programs. This proposal targets fundamental research on passive sampling - a promising sampling tool for supporting water quality monitoring.In passive sampling, organic micropollutants diffuse to the sampler surface and then partition between the water and sampler phase, typically a polymer or a bulk phase. Depending on the design of the sampler, passive samplers can be left in surface waters for days or weeks. Thus, passive samplers offer the opportunity to assess average exposure over time frames that match those of water quality criteria monitoring programs. A relatively unexplored area with these devices is how the sampling rate of a polar organic sampler (POS) can be corrected for environmental parameters that affect uptake, e.g. fouling of the sampler. Therefore we plan to do all experiments under semi-field conditions with a bypass system, flow-through channels that use water directly drawn from a river or a wastewater treatment plant but under controlled flow conditions. It is also not established how well the technique works under strongly fluctuating exposure situation as they are often encountered in small rivers and for seasonally occurring micropollutants such as pesticides. We want to address this problem by exploring the exposure situations under different designed peak exposure scenarios. We aim to develop a POS that is integrative over short and longer exposure periods - to match monitoring for acute and chronic water quality criteria - and that comes with a performance reference compounds (PRC) system to correct passive sampling data for environmental conditions. Research on the development and implementation of a PRC system is imperative for the generation of robust passive sampling data. We plan to use Empore disks as sampling phase and silicone polymer as matrix for the PRC. In addition, it has not yet been explored how well polar organic samplers mimic bioconcentration in aquatic organisms. We plan to address the fundamental question, for which classes of chemicals our passive samplers have biological relevance by comparing passive sampling directly with bioconcentration of chemicals in various aquatic organisms- algal communities grown on glass slides, the invertebrates Daphnia magna and Gammarus pulex and fish eggs. Our experi-ments will specifically deal with peak concentration scenarios, typical for the hydrological dynamics related to storm water run-off events. Specifically, we want to answer the following research questions:1. Are protected and unprotected polymer disks suitable for either long-term or short-term integrative sampling?2. Is calibration of uptake rate into POS possible both for short-term and long-term exposure?3. How does dynamic exposure affect the sampling rates of passive sampler?4. How does dynamic exposure affect the bioconcentration kinetics of aquatic organisms?5. Linking uptake in passive samplers and aquatic organisms: Do POS behave biomimetically?The main deliverables of the proposed fundamental research are a more comprehensive understanding of the behavior of polar passive samplers in relation to bioconcentration in organisms and solutions to optimize sampler performance (robustness) under environmentally realistic conditions.