Pharmaceutical compounds in marine ecosystems: ecotoxicological effects and risk assessment in phytoplankton and zooplankton.

Pharmaceutical compounds (PCs) are one of the main classes of emerging contaminants, raising concern for their potential threat to the environment. Among them, acyclovir (ACV), carbamazepine (CBZ), diclofenac (DCF), and propranolol (PRP) are the most prescribed worldwide. However, their effects on the marine environment are still little known. In this study we assessed the ecotoxicological effects of these PCs in marine phyto- and zooplankton. In particular, growth and chlorophyll inhibition, mortality, development and behaviour were assessed in several species (Dunaliella tertiolecta, Phaeodactylum tricornutum, Skeletonema pseudocostatum, Amphibalanus amphitrite, Paracentrotus lividus) after up to 72 h of exposure. Only high concentrations of any of the four PCs induced toxic effects at environmental levels. PRP was the most toxic PC towards both phyto- and zooplankton, followed by DCF, ACV, and CBZ. Environmental risk for all PCs could be estimated based on ecotoxicological responses, ranging from medium for ACV and CBZ, to high for DCF and PRP. In conclusion, all selected PCs may pose risk to marine phyto- and zooplankton. Hence, their presence and levels in the marine ecosystem should be further monitored.