Dilute Concentrations of a Psychiatric Drug Alter Behavior of Fish from Natural Populations

Abstract

Environmental pollution by pharmaceuticals is increasingly recognized as a major threat to aquatic ecosystems worldwide. A variety of pharmaceuticals enter waterways by way of treated wastewater effluents and remain biochemically active in aquatic systems. Several ecotoxicological studies have been done, but generally, little is known about the ecological effects of pharmaceuticals. Here we show that a benzodiazepine anxiolytic drug (oxazepam) alters behavior and feeding rate of wild European perch (Perca fluviatilis) at concentrations encountered in effluent-influenced surface waters. Individuals exposed to water with dilute drug concentrations (1.8 micrograms liter(-1)) exhibited increased activity, reduced sociality, and higher feeding rate. As such, our results show that anxiolytic drugs in surface waters alter animal behaviors that are known to have ecological and evolutionary consequences.

Computational consideration on advanced oxidation degradation of phenolic preservative, methylparaben, in water: mechanisms, kinetics, and toxicity assessments

“…Pharmaceuticals and personal care products (PPCPs) have raised increasing global concern because of the potential threat to drinking water safety and aquatic ecosystems [1]. Parabens, a group of important PPCPs with antimicrobial and preservative properties, are widely used in toothpastes, cosmetics, textiles, and beverages [2][3][4], resulting in approximately 8000 tons of parabens consumed annually globally [5].…”

Ecological effects of pharmaceuticals in aquatic systems—impacts through behavioural alterations

“…Most of these pharmaceuticals are designed to quickly medicate and then leave the human body without degrading, resulting in them entering freshwater systems still pharmacologically active. Even though detected concentrations of these pharmaceuticals in surface waters usually are much lower than known levels of toxicity [21,25,30], sub-lethal effects at environmentally relevant concentrations have been found in aquatic organisms [31][32][33]. Consequently, pharmaceuticals may be a 'neglected source of behavioural variation' in natural systems [34].…”

“…While most investigations of pharmaceutical effects on fish have used laboratory populations, a recent study on perch from a natural population found increased activity and decreased sociality after exposure to low mg l 21 of the benzodiazepine oxazepam and increased boldness at high mg l 21 [33] (table 2). Further, these observed behavioural changes resulted in a direct ecological effect-an increased feeding rate on zooplankton-after exposure [33].…”

Animal personality and state–behaviour feedbacks: a review and guide for empiricists

“…For example, if environmental chemicals influence behaviour in ways that increase the likelihood of being further exposed to chemicals, then even chance variation in initial encounters with contaminants, such as pesticides, heavy metals, or pharmaceuticals, could generate lasting amongindividual differences in behaviour [53,54].…”