Environmental Risk Assessment of Pharmaceuticals - Effects on Fish in a Swedish River
Conference contribution, 2014
Purpose The aim of this study was to assess exposure and chronic effects on fish from down- the-drain pharmaceuticals in the Swedish Göta Älv river. Both effects of individual pharmaceuticals and mixture effects were evaluated.
Methods Spatially resolved exposure of pharmaceuticals was modelled with the Geo- referenced Regional Environmental Assessment Tool for European Rivers (GREAT-ER) and mixture effects were calculated using the concept of concentration addition as a conservative first tier. A habitat comparison was performed by comparing the locations with high concentrations of pharmaceuticals to the locations of known habitats in the Göta Älv river for the fish Salmo salar and Salmo trutta. The modelling results were also validated by comparison with measurements of concentrations performed in other Swedish rivers. In total, 12 pharmaceuticals were studied; diclofenac, propranolol, carbamazepine, ethinylestradiol, ibuprofen, metoprolol, gemfibrozil, estradiol, paracetamol, sertraline, verapamil and estrone.
Results and discussion The results of the modelling showed that the predicted pharmaceutical concentrations in the Göta Älv river, when considered individually, generally did not cause adverse chronic effects to fish. An exception was gemfibrozil, which may cause adverse chronic effects to fish in some parts of the river. However, when mixture effects were considered, the results showed that adverse chronic effects might occur in parts of the river. The risk ratios for the mixture were relatively high (between 0.61 and 0.81) in almost all parts of the river. The two parts of the Göta Älv river catchment with the highest concentrations of the studied pharmaceuticals, were also the parts with known habitats for the studied fish species. The validation of the modelling results showed that the predicted pharmaceutical concentrations in the Göta Älv river were much lower than measured concentrations in other Swedish waters. The reasons for this were probably the large difference in both the number of people connected to the WWTPs, affecting the quantity of emitted pharmaceuticals, and the differences in dilution of the WWTP effluents in the respective surface water recipients. There are uncertainties in the results from this study due to the lack of data, especially in chronic toxicity data for the assessment endpoints Salmo salar and Salmo trutta. At the same time, the exposure of pharmaceuticals in the Göta Älv river are most probably underestimated in this study, due to the exclusion of certain sources of pharmaceuticals, having implications for the interpretation of the results.
Conclusions and perspectives The results serve as an indication of risk for chronic effects to fish in the Göta Älv river and of the importance of considering mixture effects. Further studies providing site-specific measurements would be required in order to validate these results.