Acute toxicity tests through static bioassays were conducted exposing Liza parsia separately, to copper sulphate, zinc sulphate and lead nitrate in the laboratory. The 96 hr LC50 values found were 85.6, 60.3 and 103.5 ppm for copper sulphate, zinc sulphate and lead nitrate respectively. The 96 hr LC5Os calculated for elementary copper, zinc and lead were 21.8, 13.7 and 64.7 ppm respectively. Based on 12 hr LC50 the copper was found more toxic than zinc and lead. In 24, 48, 72 and 96 hr LC50s the zinc was found more toxic to the experimental animals than copper and lead. The animals were experimented in salinity 9.8 * 0.76%0, pH 7.19 * 0.12, temperature 28.0 -L 1.5OC and total hardness 2956.0 t 142.2 ppm.

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