From gender benders to brain benders (and beyond!)

The impact of pharmaceuticals in the environment has been aconcern for several decades (Cleuvers, 2003; Ferrari et al., 2003;Fent et al., 2006; Santos et al., 2010). Following on from the fieldof endocrine disrupting chemicals (EDCs) in the early 1990s, whereawareness to population level effects of sub-lethal chemicals wereraised, the scientific community was alerted to the potential impactof antidepressants over a decade ago (Fong et al., 1998; Fong, 2001;Brooks et al., 2003; Brook et al 2005). A considerable amount ofresearch on EDCs was based around synthetic estrogens and oestro-gen mimics/agonists (Tyler et al., 1998; Länge et al., 2001; Sumpterand Johnson, 2005) resulting in a focussed international researcheffort that culminated in a vast body of research. Interestingly, anddespite the fact that in some countries the prescriptions for con-traceptive pills and those for antidepressants are broadly similar(∼8–9% of the population; USDHHP, 2012); and both compoundsare found at low ng/L concentration in the environment, the bodyof ecotoxicological work covering effects of synthetic estrogenshugely grosses that of the antidepressants. Why there has not beenmore research into the antidepressants is not entirely clear butmay have occurred for a variety of reasons. Firstly, the numbersof studies recording these compounds in aquatic systems werepreviously low and secondly the effects of antidepressants thatwere recorded were at relatively high concentrations arguably dueto the endpoints available at the time and thus perhaps did notstimulate the field. In addition, the field of behavioural ecotoxicol-ogy, despite coming a long way is still developing. Therefore, it isarguably more difficult to extrapolate aberrant behaviour of aquaticorganisms into risk assessment compared to impacts observedon reproductive systems, growth and mortality. And finally, theresearch funding for the field of ecotoxicology is ever transient andantidepressants are one small group of pharmaceuticals amongstmany thousands needing to be fully evaluated for their impact onthe environment.