Water is a vital resource for natural ecosystems and human life, and assuring a high quality of water and protecting it from chemical contamination is a major societal goal in the European Union. The Water Framework Directive (WFD) and its daughter directives are the major body of legislation for the protection and sustainable use of European freshwater resources. The practical implementation of the WFD with regard to chemical pollution has faced some challenges. In support of the upcoming WFD review in 2019 the research project SOLUTIONS and the European monitoring network NORMAN has analyzed these challenges, evaluated the state-of-the-art of the science and suggested possible solutions. We give 10 recommendations to improve monitoring and to strengthen comprehensive prioritization, to foster consistent assessment and to support solution-oriented management of surface waters. The integration of effect-based tools, the application of passive sampling for bioaccumulative chemicals and an integrated strategy for prioritization of contaminants, accounting for knowledge gaps, are seen as important approaches to advance monitoring. Including all relevant chemical contaminants in more holistic "chemical status" assessment, using effect-based trigger values to address priority mixtures of chemicals, to better consider historical burdens accumulated in sediments and to use models to fill data gaps are recommended for a consistent assessment of contamination. Solution-oriented management should apply a tiered approach in investigative monitoring to identify toxicity drivers, strengthen consistent legislative frameworks and apply solutions-oriented approaches that explore risk reduction scenarios before and along with risk assessment.

• Keywords
• Chemical legislation, Effect-based tools, Passive sampling, Prioritization of contaminants, Solution-oriented management, Water Framework Directive review,
• Publication type
• Journal Article MeSH

Several bacteria-based assays, notably Vibrio fischeri luminescence assays, are often used as environmental monitoring tool for toxicity in sediments that may serve as both sinks and secondary source of contamination in aquatic ecosystems. In this study, we used 30-s kinetic bioassays based on V. fischeri to evaluate the toxicity associated to sediments from five localities with different contamination inputs (Morava River and its tributary Drevnice River in the south-eastern part of the Czech Republic). Toxicity assessed as half maximal inhibitory concentration (IC50) over the course of a year-long sampling was compared in bottom sediments and freshly trapped particulate material. Standard approach based on testing of aqueous elutriates was compared with toxicity of whole sediments (contact suspension toxicity). Bottom sediments showed lower toxicity compared to freshly trapped suspended materials in all cases. On the other hand, standardized elutriates induced generally weaker effects than suspended sediments likely due to losses during the extraction process. Toxicity generally increased during winter reaching maximum peaks in early spring months in all five sites. Total organic carbon (TOC) was found to be highly correlated with toxic effects. Toxicity from sites with direct industrial and agricultural water inputs also correlated with concentrations of metals, polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs). Single time point sampling followed by the extraction and testing of elutriates, do not truly reflect the spatial and temporal variability in natural sediments and may lead to underestimation of ecotoxic risks.

• Keywords
• Vibrio fischeri, monitoring, seasonality, sediment, toxicity,
• Publication type
• Journal Article MeSH

To assess the long-term anthropogenic load of the Bílina River (Czech Republic), the concentrations of heavy metals and specific organic compounds in different river ecosystem matrices (water, biofilms, and sediments) were determined. Although the current concentrations of pollutants in surface water are low, frequently below the limits of the quantitative analytical methods used, the river ecosystem is still heavily loaded by anthropogenic pollution, mainly from the chemical and mining industries. This was demonstrated by analyzing biofilms and sediments. These matrices are more accurate representatives of the actual situation in the river and do not depend on hydrological conditions or random variability in water quality. The results indicate that the middle and the lower parts of the river are heavily polluted by mercury, arsenic, vanadium, polychlorinated biphenyls, hexachlorobenzene, and dichloro-diphenyl-trichloroethane. As a tributary of the Elbe River, the Bílina River represents a significant risk for the development of quality in this major European river.

• MeSH
• Biofilms * MeSH
• Water Pollutants, Chemical analysis   MeSH
• Geologic Sediments chemistry   MeSH
• Organic Chemicals analysis   MeSH
• Data Collection MeSH
• Fresh Water chemistry   MeSH
• Metals, Heavy analysis   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Geographicals
• Czech Republic MeSH
• Names of Substances
• Water Pollutants, Chemical MeSH
• Organic Chemicals MeSH
• Metals, Heavy MeSH