TITLE:
Evaluation of Acute Chromium (III) Toxicity in Relation to Daphnia Similis
AUTHORS:
Petr Melnikov, Tânia C. M. de Freitas
KEYWORDS:
Water pollution, Chromium (III), Daphnia similis, Acute toxicity test
JOURNAL NAME:
Journal of Water Resource and Protection,
Vol.3 No.2,
February
28,
2011
ABSTRACT: Acute chromium (III) toxicity in relation to Daphnia similis, most appropriate for Brazilian environment has been evaluated. The preliminary toxicity test showed that the median effective concentration was 10 mg/l. After having performed the final test, the immobility percentage was calculated for each concentration in relation to the total number of the used organisms within the chosen pH range. It was shown that the proposed methodology rendered realistic results and the 48-h CE50 value under the test conditions is 3.24 mg/l. The minimum concentration that did not show any toxicity to Daphnia similis was 2.5 mg of chromium (III) per liter. The obtained level is superior to the maximum limit recommended by the Brazilian norms, 0.5 mg/l.