Widespread pharmaceutical exposure at concentrations of concern for a subtropical coastal fishery: Bonefish (Albula vulpes)

Pharmaceuticals have been acknowledged as an important contaminant of emerging concern with the potential to cause adverse effects in exposed fauna. Most research has focused on temperate freshwater systems; therefore, there is a pressing need to quantify pharmaceutical exposure in subtropical coastal marine systems. This study investigated the prevalence of pharmaceutical exposure to bonefish (Albula vulpes) in subtropical South Florida, USA, and evaluated the relative risk of detected concentrations to elicit pharmacological effects. The influence of sampling region, season (within or outside spawning season), and bonefish length on pharmaceutical assemblage, detection frequency, and risk was assessed. Both spatial (multiple regions) and temporal (spawning season) components were considered in order to incorporate bonefish biology biological in our exploration of pharmaceutical exposure and potential risk of effect. To quantify risk of pharmacological effects, concentrations were compared to a 1/3 threshold of the human therapeutic plasma concentration (H_TPC). In total, 53 different pharmaceuticals were detected with an average of 7.1 pharmaceuticals per bonefish and 52.3 % had at least one pharmaceutical exceeding the 1/3 H_TPC threshold. The presence of pharmaceutical cocktails at concentrations capable of eliciting pharmacological effects is of particular concern considering the potential for unknown interactions. For exposure and risk of pharmacological effect, region and season were significant, while bonefish length was not. Pharmaceutical exposure and risk were highest in the most remote sampling region. Results establish pharmaceuticals' widespread prevalence in subtropical coastal marine ecosystems, exposure and risk to biota, and the necessity to examine marine systems.