Exposure via biotransformation: Oxazepam reaches predicted pharmacological effect levels in European perch after exposure to temazepam

Abstract It is generally expected that biotransformation and excretion of pharmaceuticals occurs similarly in fish mammals, despite significant physiological differences. Here, we exposed European perch (Perca fluviatilis) to the benzodiazepine drug temazepam at a nominal concentration 2 µg L?1 for 10 days. We collected samples blood plasma, muscle, brain time-dependent manner assess its bioconcentration, biotransformation, elimination over another days depuration clean water. observed rapid pharmacokinetics during both exposure periods. The steady state was reached within 24 h most individuals, as complete from tissues depuration. Further, biologically active metabolite oxazepam produced via accumulated significantly throughout period. In contrast human patients, where negligible amount created by continuous increase concentrations all exposure. Indeed, more than parent compound, did not reach period, completely eliminated even after depuration, highlighting importance considering environmental hazards posed pharmaceutical metabolites.