Acute Toxicity Study of Heavy Metal Chromium and Tannery Effluent Water in Water Flea,Daphnia magna Straus by Bioassay Method

Abstract

An acute toxicity test for each metal measures the deleterious effect of an organism over a short-term exposure. Whole effluent toxicity (WET) test has been widely used overseas to assess the potential toxicity of effluents. The results of these tests can be used for a variety of functions including resource consent monitoring and compliance, toxicity identification evaluations and evaluation of effluent treatment processes. The acute toxicity study of heavy metal chromium as well as tannery effluent (chromium containing) water have been evaluated by laboratory bioassay experiments for 48 h duration in water flea, Daphnia magna Straus. The median lethal concentration (LC $_{50}$ ) value of chromium metal for 48 h duration was determined to be 0.4027 ppm. WET test confirmed median lethal concentration (LC $_{50}$ ) values of tannery effluent water for 48 h duration was 6.540% dilutions respectively. Chromium content in tannery effluent water was found 3.47 ppm which is quite higher from different water quality standards.