Exposure and ecotoxicological risk assessment of mixtures of top prescribed pharmaceuticals in Swedish freshwaters.

Surface water concentrations of 54 pharmaceuticals were predicted for seven major Swedish rivers and the Stockholm City area basins using the STREAM-EU model. These surface water concentrations were used to predict the ecotoxicological impact resulting from the exposure of aquatic organisms to this mixture of 54 pharmaceuticals. STREAM-EU model results indicated that <10 substances were present at median annual water concentrations greater than 10 ng/L with highest concentrations occurring mostly in the more densely populated area of the capital city, Stockholm. There was considerable spatial and temporal variability in the model predictions (1-3 orders of magnitude) due to natural variability (e.g. hydrology, temperature), variations in emissions and uncertainty sources. Local mixture ecotoxicological pressures based on acute EC50 data as well as on chronic NOEC data, expressed as multi-substance potentially affected fraction of species (msPAF), were quantified in 114 separate locations in the waterbodies. It was estimated that 5% of the exposed aquatic species would experience exposure at or above their acute EC50 concentrations (so-called acute hazardous concentration for 5% of species, or aHC5) at only 7% of the locations analyzed (8 out of 114 locations). For the evaluation based on chronic NOEC concentrations, the chronic HC5 (cHC5) is exceeded at 27% of the locations. The acute mixture toxic pressure was estimated to be predominantly caused by only three substances in all waterbodies: Furosemide, Tramadol and Ibuprofen. A similar evaluation of chronic toxic pressure evaluation logically demonstrates that more substances play a significant role in causing a higher chronic toxic pressure at more sites as compared to the acute toxic pressure evaluation. In addition to the three substances contributing most to acute effects, the chronic effects are predominantly caused by another five substances: paracetamol, diclofenac, ethinylestradiol, erythromycin and ciprofloxacin. This study provides regulatory authorities and companies responsible for water quality valuable information for targeting remediation measures and monitoring on a substance and location basis.

How to calculate the spatial distribution of ecosystem services--natural attenuation as example from The Netherlands.

Maps play an important role during the entire process of spatial planning and bring ecosystem services to the attention of stakeholders' negotiation more easily. As example we show the quantification of the ecosystem service 'natural attenuation of pollutants', which is a service necessary to keep the soil clean for production of safe food and provision of drinking water, and to provide a healthy habitat for soil organisms to support other ecosystem services. A method was developed to plot the relative measure of the natural attenuation capacity of the soil in a map. Several properties of Dutch soils were related to property-specific reference values and subsequently combined into one proxy for the natural attenuation of pollutants. This method can also be used to map other ecosystem services and to ultimately integrate suites of ecosystem services in one map.

Integrated Risk Assessment for WFD Ecological Status classification applied to Llobregat river basin (Spain). Part II - Evaluation process applied to five environmental Lines of Evidence.

Many indicators and indices related to a variety of biological, physico-chemical, chemical, and hydromorphological water conditions have been recently developed or adapted by scientists in order to support water managers in the Water Framework Directive (WFD) implementation. In this context, the achievement of a comprehensive and reliable Ecological Status classification of water bodies across Europe is hampered by the lack of harmonised procedures for selecting an appropriate set of indicators and integrating heterogeneous information in a flexible way. To this purpose, an Integrated Risk Assessment (IRA)(2) methodology was developed based on the Weight of Evidence approach. This method analyses and combines a set of environmental indicators grouped into five Lines of Evidence (LoE), i.e. Biology, Chemistry, Ecotoxicology, Physico-chemistry and Hydromorphology. The whole IRA methodology has been implemented as a specific module into a freeware GIS (Geographic Information System)-based Decision Support System, named MODELKEY DSS. This paper focuses on the evaluation of the four supporting LoE (i.e. Chemistry, Ecotoxicology, Physico-chemistry and Hydromorphology), and includes a procedure for a comparison of each indicator with proper thresholds and a subsequent integration process to combine the obtained output with the LoE Biology results in order to provide a single score expressing the Ecological Status classification. The approach supports the identification of the most prominent stressors, which are responsible for the observed alterations in the river basin under investigation. The results provided by the preliminary testing of the IRA methodology through application of the MODELKEY DSS to the Llobregat case study are finally reported and discussed.

Integrated risk assessment for WFD ecological status classification applied to Llobregat river basin (Spain). Part I-Fuzzy approach to aggregate biological indicators.

Water Framework Directive (WFD) requirements and recommendations for Ecological Status (ES) classification of surface water bodies do not address all issues that Member States have to face in the implementation process, such as selection of appropriate stressor-specific environmental indicators, definition of class boundaries, aggregation of heterogeneous data and information and uncertainty evaluation. In this context the "One-Out, All-Out" (OOAO) principle is the suggested approach to lead the entire classification procedure and ensure conservative results. In order to support water managers in achieving a more comprehensive and realistic evaluation of ES, an Integrated Risk Assessment (IRA) methodology was developed. It is based on the Weight of Evidence approach and implements a Fuzzy Inference System in order to hierarchically aggregate a set of environmental indicators, which are grouped into five Lines of Evidence (i.e. Biology, Chemistry, Ecotoxicology, Physico-chemistry and Hydromorphology). The whole IRA methodology has been implemented as an individual module into a freeware GIS (Geographic Information System)-based Decision Support System (DSS), named MODELKEY DSS. The paper focuses on the conceptual and mathematical procedure underlying the evaluation of the most complex Line of Evidence, i.e. Biology, which identifies the biological communities that are potentially at risk and the stressors that are most likely responsible for the observed alterations. The results obtained from testing the procedure through application of the MODELKEY DSS to the Llobregat case study are reported and discussed.

Toxicity assessment of sediments from three European river basins using a sediment contact test battery.

The toxicity of four polluted sediments and their corresponding reference sediments from three European river basins were investigated using a battery of six sediment contact tests representing three different trophic levels. The tests included were chronic tests with the oligochaete Lumbriculus variegatus, the nematode Caenorhabditis elegans and the mudsnail Potamopyrgus antipodarum, a sub-chronic test with the midge Chironomus riparius, an early life stage test with the zebra fish Danio rerio, and an acute test with the luminescent bacterium Vibrio fischeri. The endpoints, namely survival, growth, reproduction, embryo development and light inhibition, differed between tests. The measured effects were compared to sediment contamination translated into toxic units (TU) on the basis of acute toxicity to Daphnia magna and Pimephales promelas, and multi-substance Potentially Affected Fractions of species (msPAF) as an estimate for expected community effects. The test battery could clearly detect toxicity of the polluted sediments with test-specific responses to the different sediments. The msPAF and TU-based toxicity estimations confirmed the results of the biotests by predicting a higher toxic risk for the polluted sediments compared to the corresponding reference sediments, but partly having a different emphasis from the biotests. The results demonstrate differences in the sensitivities of species and emphasize the need for data on multiple species, when estimating the effects of sediment pollution on the benthic community.

Treatment of chronic osteomyelitis with ciprofloxacin.

Twenty-seven patients with chronic osteomyelitis were treated with oral ciprofloxacin, 500 mg (13 patients) or 750 mg (13) twice daily and one patient was treated with 300 mg twice daily intravenously. Treatment was given for 17-189 days (mean 69). Twenty-three patients had prosthetic implants, 16 patients had infections caused by one bacterium and 11 had polymicrobial infections. The predominant organisms were strains of Enterobacteriaceae, Pseudomonas aeruginosa and Staphylococcus aureus. Cure was obtained in 20 patients and improvement in four. Three patients failed to respond to therapy. Concentrations of ciprofloxacin, measured in pus 1 h after 500 mg orally ranged from 0.6-1.3 mg/l, whilst 2 h after 750 mg orally concentrations of 2.4-6.8 mg/l were found. Sterilization of pus and closure of infected wounds or draining sinuses were observed within four weeks of treatment in the majority of patients. Ciprofloxacin was well tolerated in 26 patients, whilst one had severe nausea after oral administration.

Bio-indicators and chemical pollution of surface waters.

Attention is given to two different approaches to determine the water quality in relation to toxic stress.The first approach is based on direct observations on the state of health of the biota naturally occurring in the environment to be judged. In the original concept of biological indicators of water pollution the existence of differences in stress-susceptibility of different species is assumed. However, toxicity studies indicated that there are no species whose absence or presence gives information on the degree of toxic pollution. When attention is solely directed to health aspects of one species, a higher specificity and response-rate is obtained, but water quality indexing is not possible. Examples of effects of chemical pollution on the health of fish from the river Rhine are presented.The second approach is based on indirect observations, determining the water quality by examination of the state of health of organisms experimentally exposed to the water under controlled conditions. To save testing time it is useful to concentrate the toxic compounds prior to testing. An example of these methods is given, describing the water quality of the rivers Rhine and Meuse in terms of toxicity and mutagenicity.As both approaches are complementary with respect to ecological significance and specificity, it is recommended to apply them simultaneously to obtain appropriate information on environmental quality and stress factors.