Chemical evaluation of effluent from a pharmaceutical industry using <i>Tympanotonus fuscatus</i>

Abstract

The study was conducted to evaluate the effect of pharmaceutical effluent from an industry located at Sango Otta, Ogun State on Tympanotonos fuscatus. It was used to assess the possible impacts of the effluent on aquatic life using periwinkle (Tympanotonus fuscatus). Samples of the pharmaceutical effluent were collected several times at the company’s discharge point via an outlet immediately after production . Physico-chemical characteristics, twelve (12) in all, and five (5) heavy metal contents were analysed and determined. The heavy metals included Fe, Pb, Zn, Mn and Hg using Atomic Absorption Spectrophotometer (AAS- Unican 919 series). Exposure of the pharmaceutical effluent at different concentrations of toxicant (0, 5, 10, 15, 20 and 25 ml/L) to test organisms was done in replicates. The mean mortality of the periwinkles increased with concentration and time. Consequently, the 96 hr LC50 value obtained for the effluent was 4.92 ml/L at the mean lethal time (MLT 50). The pH value was 5.1; EC, 187 uS cm-1; DO, 2.4 mg/L; BOD, 80 mg/L; NO3-, 3.15 mg/L and Cl-, 100 mg/L. The level of some heavy metals was above the internationally recommended maximum contaminant level of WHO and USEPA, except for mercury which was not detected. Wastewaters discharged into water bodies do ultimately pose a serious threat to human and routine functioning of ecosystem. Regular and proper treatment of effluents among others before disposal to safeguard the environment is suggested.