Monitoring of the booster biocide dichlofluanid in water and marine sediment of Greek marinas

Dichlofluanid (N-dichlorofluoromethylthio-N'-dimethyl-N-phenylsulphamide) is used as booster biocide in antifouling paints. The occurrence of dichlofluanid and its metabolite DMSA (N'-dimethyl-N-phenyl-sulphamide) was monitored in seawater and marine sediment from three Greek marinas. Seawater and sediment samples were collected at three representative positions and one suspected hotspot in each marina and shipped to the laboratory for chemical analysis. As part of the project, an analytical method had been developed and validated. Furthermore, some additional experiments were carried out to investigate the potential contribution of paint particle bound dichlofluanid on the total concentration in the sediment. As expected, given its known high hydrolytic degradation rate, no detectable concentrations of dichlofluanid were measured in any of the seawater samples. DMSA was detected in seawater samples at very low concentrations varying from <3 ng l(-1) (LOD) to 36 ng l(-1). During method validation, it had already been demonstrated that dichlofluanid is unstable in sediment and can therefore only be determined as its metabolite DMSA. In a separate experiment, in which marine sediment was spiked with artificial paint particles containing dichlofluanid and then analysed according to the validated method, it was demonstrated that if there is any dichlofluanid originating from paint particles, this would be determined as DMSA. No DMSA was detected in any of the sediment samples. It could therefore be concluded that there were no significant concentrations of dichlofluanid in the sediment samples.     

The detection of chronic biological effects in the marine intertidal bivalve cerastoderma edule, in model ecosystem studies with pulverised fuel ash: reproduction and histopathology

The cockle Cerastoderma edule was exposed to sediments variously comprised of pulverised fuel ash (PFA) for two consecutive periods of 3 and 9 months. Chronic effects of PFA on this filter feeding bivalve were studied by examining changes in cellular and tissue pathology with the aid of a screening procedure developed for analysing histopathology conditional. The mortality rate was high, up 43% for the 100% PFA sediment and growth of the individual bivalves was low. The accumulation of metals appeared to be low at 1-10 times background tissue levels. Signs of cellular stress were seen in the digestive gland after the first 3 months. However, after 9 months, this same organ was in fairly good condition. Reproduction was delayed due to slow oocyte maturation.     

MODELKEY

The EU Water Framework Directive (WFD) requires the achievement of good ecological and chemical status in European river basins. However, evidence is increasing that a majority of European water bodies will not achieve this goal. Nutrient emissions and related eutrophication together with hydromorphological alterations have been suggested as the major driving forces of this insufficient ecological status. MODELKEY (511237 GOCE, FP6) provides strong evidence that toxic chemicals also affect the ecological status of European rivers. This was demonstrated in the case study rivers Elbe, Scheldt and Llobregat on different scales. This paper summarises key findings of MODELKEY including recommendations for WFD implementation. We ? provide evidence of toxic stress in aquatic ecosystems, ? provide evidence that impairment of ecological status results from impact of multiple stressors, ? suggest a tiered approach to assess impact of chemicals on ecological status, ? suggest a new approach for deriving candidate compounds for monitoring and prioritisation, ? call for consideration of bioavailability and bioaccumulation in chemical status assessments, ? suggest improvements for WFD water quality monitoring programmes, ? provide new integrated tools for basin-scale risk assessment and decision making, ? developed a Decision Support System to support river basin management. These key results will be presented in a series of ten integrated sections; for the scientific details please refer to publications listed on the MODELKEY website (http://www.modelkey.org/). This article also looks beyond MODELKEY and proposes a combination of MODELKEY diagnostic tools with recent ecological methods to further improve effectiveness of river basin management.