Effects of a complex mixture of therapeutic drugs on unicellular algae Pseudokirchneriella subcapitata

Pharmaceutically-active compounds are regularly and widely released into the aquatic environment in an unaltered form or as metabolites. So far, little is known about their potential detrimental effects on algae populations which can ultimately impact nutrient cycling and oxygen balance. For our analysis, the common microalga Pseudokirchneriella subcapitata (P. subcapitata) was exposed to a mixture of 13 drugs found in Italian wastewaters and rivers. Traces of pharmaceuticals investigated were detected in treated algal cells, except for cyclophosphamide and ranitidine, indicating that these algae are able to absorb pharmaceutical pollutants from the environment. The effects of the treatment were investigated by Amplified Fragment Length Polymorphism (AFLP) assessment of DNA damage and 2-DE proteomic analysis. While no genotoxic effect was detected, proteomic analysis showed that algae are sensitive to the presence of drugs and that, in particular, the chloroplast is affected. (C) 2010 Elsevier B.V. All rights reserved.