Meeting Abstract
Pharmaceutical pollution is an emerging environmental concern, with a wide variety of medications appearing in surface waters around the world. In the environment, UV radiation can cause many pharmaceuticals to transform into related molecules, which may be more toxic than the original compound. Despite increasing attention to the effects of various pharmaceuticals on aquatic life, very little is known about the ecotoxicology of these pharmaceuticals’ transformation products. This study examined the effects of the widely-prescribed antidepressant fluoxetine (Prozac) and its transformation products on amphibian larvae. Throughout larval development, tadpoles of the southern toad (Anaxyrus terrestris) were exposed either to untransformed fluoxetine or to fluoxetine that had undergone UV phototransformation. Tadpoles experienced similar growth reduction in the two treatments, even though the total concentration of fluoxetine and its transformation products was lower in the phototransformed treatment. This result suggests that tadpole growth was more strongly affected by the transformation products than by fluoxetine itself. By contrast, tadpoles exposed to untransformed fluoxetine showed a more dramatic reduction in activity than did those in the phototransformed treatment, suggesting that the effects on activity were mostly attributable to fluoxetine rather than its transformation products. Because UV phototransformation of fluoxetine results in compounds that may be more harmful than fluoxetine itself, levels of these transformation products, as well as fluoxetine, should be monitored in the environment. More generally, when evaluating the risks posed by pharmaceuticals in the environment, their phototransformation products must also be considered.
