Because it is impossible to chemically analyze all relevant micropollutants, the implementation of bioanalytical tools is essential to estimate ecological risks of chemical mixtures in regular water-monitoring programs. The first tier of the Smart Integrated Monitoring (SIMONI) strategy, which was described in part I, is based on the combination of passive sampling and bioanalytical measurements. Bioassay responses are compared with effect-based trigger values (EBT), and an overall SIMONI score on all bioassay data was designed to indicate environmental risks. The present study is focused on analyzing the feasibility of the hazard identification tier by evaluating results of 45 field campaigns at sites with different pollution profiles near the city of Amsterdam. A Daphnia assay was performed in situ, while silicon rubber or polar organic chemical integrative sampler (POCIS) extracts were tested with 4 nonspecific (daphnids, algae, bacteria, and cell culture) and 10 specific (9 Chemical Activated Luciferase Gene Expression [CALUX] assays and antibiotics scan) bioassays. Sensitivity analyses demonstrated the relevance of 2 classification variables in the SIMONI score formula on all bioanalytical data. The model indicated increased risks for the ecosystem at surface waters in greenhouse areas and undiluted wastewater-treatment plant (WWTP) effluents. The choice of testing specific bioassays on either polar or nonpolar passive sampling extracts is cost-effective and still provided meaningful insights on micropollutant risks. Statistical analyses revealed that the model provides a relevant overall impact assessment based on bioassay responses. Data analyses on the chemically determined mixture toxic pressure and bioanalytical methods provided similar insights in relative risk ranking of water bodies. The SIMONI combination of passive sampling and bioanalytical testing appears to be a feasible strategy to identify chemical hazards.
- Bioanalytical tool
- Environmental risk assessment
- Passive sampling