Suchergebnisse

Contamination of surface waters by pesticides continues to be the focus of concern for water authorities due to the growing evidence of their deleterious effects on aquatic life. In this context, the present work investigates the occurrence of 16 selected pesticides belonging to the classes of triazines, phenylureas, organophosphates, chloroacetanilides and thiocarbamates in surface waters from the Llobregat River (NE Spain) and some of its tributaries (Anoia and Rubí) and assesses their potential impact on the aquatic organisms by applying a recently developed index, the Short-term Pesticide Risk Index for the Surface Water System (PRISW-1), which takes into account the pesticides concentrations and their overall toxicity against three aquatic organisms (algae, Daphnia, and fish). Chemical analysis, performed by means of a fully automated method based on isotope dilution on-line solid phase extraction–liquid chromatography– electrospray–tandem mass spectrometry (on-line SPE–LC–ESI–MS/MS), revealed diuron and diazinon as the most ubiquitous and abundant compounds with levels up to 818 and 132 ng L 1, respectively. Total pesticide concentrations, which in only 1 out of 66 samples surpassed 500 ng L 1, were higher in the tributaries than in the river but their contribution in terms of mass-loads to the overall pesticide pollution of the Llobregat River was relatively small. Contamination increased downstream of the river and was clearly influenced by rainfall and hence river flow. Application of the PRISW-1 index indicated that, although pesticides levels fulfilled the European Union Environmental Quality Standards (EQS) for surface waters, the existing pesticide contamination poses a low to high ecotoxicological risk for aquatic organisms, that algae and macro-invertebrates are at higher risk than fish, and that the organophosphates diazinon and malathion and the phenylurea diuron are the major contributors to the overall toxicity and therefore the most problematic compounds. ; Peer Reviewed ; Postprint (published version)

Contamination of surface waters by pesticides continues to be the focus of concern for water authorities due to the growing evidence of their deleterious effects on aquatic life. In this context, the present work investigates the occurrence of 16 selected pesticides belonging to the classes of triazines, phenylureas, organophosphates, chloroacetanilides and thiocarbamates in surface waters from the Llobregat River (NE Spain) and some of its tributaries (Anoia and Rubí) and assesses their potential impact on the aquatic organisms by applying a recently developed index, the Short-term Pesticide Risk Index for the Surface Water System (PRISW-1), which takes into account the pesticides concentrations and their overall toxicity against three aquatic organisms (algae, Daphnia, and fish). Chemical analysis, performed by means of a fully automated method based on isotope dilution on-line solid phase extraction–liquid chromatography– electrospray–tandem mass spectrometry (on-line SPE–LC–ESI–MS/MS), revealed diuron and diazinon as the most ubiquitous and abundant compounds with levels up to 818 and 132 ng L 1, respectively. Total pesticide concentrations, which in only 1 out of 66 samples surpassed 500 ng L 1, were higher in the tributaries than in the river but their contribution in terms of mass-loads to the overall pesticide pollution of the Llobregat River was relatively small. Contamination increased downstream of the river and was clearly influenced by rainfall and hence river flow. Application of the PRISW-1 index indicated that, although pesticides levels fulfilled the European Union Environmental Quality Standards (EQS) for surface waters, the existing pesticide contamination poses a low to high ecotoxicological risk for aquatic organisms, that algae and macro-invertebrates are at higher risk than fish, and that the organophosphates diazinon and malathion and the phenylurea diuron are the major contributors to the overall toxicity and therefore the most problematic compounds. ; Peer Reviewed ; Postprint (published version)

The contamination of marine ecosystems by contaminants of emerging concern such as personal care products or per- and polyfluoroalkyl substances is of increasing concern. This work assessed the concentrations of selected contaminants of emerging concern in water and sediment of European aquaculture areas, to evaluate their co-variation with legacy contaminants (polycyclic aromatic hydrocarbons) and faecal biomarkers, and estimate the risks associated with their occurrence. The 9 study sites were selected in 7 European countries to be representative of the aquaculture activities of their region: 4 sites in the Atlantic Ocean and 5 in the Mediterranean Sea. Musks, UV filters, preservatives, per- and polyfluoroalkyl substances and polycyclic aromatic hydrocarbons were detected in at least one of the sites with regional differences. While personal care products appear to be the main component of the water contamination, polycyclic aromatic hydrocarbons were mostly found in sediments. As expected, generally higher levels of personal care products were found in sewage impacted sites, urbanised coasts and estuaries. The risk assessment for water and sediment revealed a potential risk for the local aquatic environment from contaminants of both legacy and emerging concern, with a significant contribution of the UV filter octocrylene. Despite marginal contributions of per- and polyfluoroalkyl substances to the total concentrations, PFOS (perfluorooctane sulfonate) aqueous concentrations combined to its low ecotoxicity thresholds produced significant hazard quotients indicating a potential risk to the ecosystems. ; This study was financially supported by the SEA-on-a-CHIP project, funded from European Union Seventh Framework Programme (FP7-OCEAN-2013) under grant agreement No. 614168. Antonio Marques is supported through the FCT Investigator program (IF). ; Peer reviewed