Pharmaceutical contamination of the aquatic ecosystem has become an emerging challenge because of their impact on non-target aquatic organism. The sub lethal effect of naproxen-a non-steroid anti-inflammatory drug was studied for 28 days in a semi-static bioassay system on the African fresh water catfish (Clarias gariepinus). Acute toxicity study was carried out to determine the median lethal concentration (LC50) of the pharmaceutical. After the LC50, of the drug was determined, the fish was exposed to 0.0 mg/L (control) and the different sub-lethal concentrations of naproxen (3.46, 2.31 and 1.73 mg/L which are 1/10th, 1/15th, and 1/20th of the LC50 of naproxen, respectively). The fish blood, brain, liver and gill were assessed to study the effects of the drug on haematological, biochemical, oxidative stress and neurotoxic parameters in the fish. The fish was exposed to the drug for 21 days followed by depuration for 7 days. The study revealed significant reduction (p p Clarias gariepinus juveniles by the evidenced negative impact on the parameters studied and should, therefore, be closely monitored in the aquatic environment.
Melefa et al. (Mon,) studied this question.