Starlings on Prozac: How pharmaceuticals may affect wildlife
How do psychiatric pharmaceuticals and their metabolites affect wildlife after they are excreted into the environment? This is an important line of inquiry because pharmaceuticals, which are specifically designed to alter human physiology and behaviour at low concentrations, can also affect other vertebrates. For example, it has recently been found that nestling wild starlings, Sturnus vulgaris, grow more slowly and show poorer immune response than controls when fed endocrine-disrupting chemicals, including 17α-ethinylestradiol, a common ingredient of the contraceptive pill (doi:10.1111/j.1365-2664.2010.01931.x). But so far, studies of the effects upon wildlife of environmentally relevant concentrations of pharmaceuticals are rare, particularly for terrestrial species and exposure routes.
This inspired Kate Arnold, a Royal Society University Research Fellow in the environment department at the University of York, to investigate the effects of the commonly prescribed psychiatric pharmaceutical, fluoxetine (Prozac), upon wild starlings. In the environment, this antidepressant and its metabolites originate from human waste and are present in surface water at concentrations as high as the µg l-1 level. (For reference, the therapeutic dose of fluoxetine is 20 to 60 mg orally per day for an adult.)
Birds in the treatment group showed conspicuous changes in foraging behaviour from controls.
Tom G. Bean, Alistair B. A. Boxall, Julie Lane, Katherine A. Herborn, Stéphane Pietravalle and Kathryn E. Arnold (2014). Behavioural and physiological responses of birds to environmentally relevant concentrations of an antidepressant, Philosophical Transactions of the Royal Society B: Biological Sciences, 369 (1656) 20130575-20130575. doi:10.1098/rstb.2013.0575
Adult common starling, Sturnus vulgaris. Photograph: Liz Leyden/Getty Images
