Acute Toxicity Tests Of Brewery Effluent on the Ostracoda, Strandesia Prava Klie, 1935 (Crustacea, Ostracoda)

Abstract

The acute toxicity of brewery effluent to Strandesia prava Klie (crustacean, ostracoda) was determined in 24, 48 and 96 hour static bioassay under laboratory conditions. The test was conducted in replicates of 100, 50, 25, 12.5, 6.25 and 3.125% effluent concentrations. Mortality of the test organism increased with the increase in the effluent concentrations. S. prava 24, 48 and 96- h LC₅₀ wasb15.21, 6.53 and 10% respectively, while 24 h- LC₅₀ of 15.21% was the least toxic to the test organism. Median lethal time, LT₅₀ for 100, 50, 25, 12.5, and 6.25% effluent concentrations were 398.11 (6.6 hours), 1000 (16.7 hours), 1258.93 (21 hours), 2238.70 (37.3 hours) and 2818.38 minutes (47 hours). Mortality also varied with the concentrations. The toxic effect of brewery effluent on ostracoda, which plays an important role in the aquatic food chain and the possibility that they may be accumulating some of these toxic components, is a matter for concern.

Keywords:  Toxicity, rewery effluent, Ostracoda, Strandesia, crustacea