Effects of Water Hardness and Metal Concentration on a Freshwater Tubifex Tubifex Muller

摘要: The present investigation was designed to determine the effectsof water hardness and heavy metals concentrations on a freshwaterTubifex tubifex. Very few data concerning effect of acute toxicity are available T. tubifex, which has been proposed as testorganism for ecotoxicological studies. is discussed. acutetoxicity selected freshwater tubifex Muller determined in very soft, hard veryhard (12, 45, 170 300 mg CaCO3 L-1 total hardness,respectively) water. Percentage mortality influenced by studied variable hardness. Water had significant metalstoxicity. necessary immobilize 50% test animals at 24, 48, 72, 96 hr were significantlydifferent soft EC50 valuesfor higher watercompared with Median effectiveconcentrations (EC50) their 95% confidence limits weredetermined cadmium, cobalt, chromium, copper, iron, lead, manganese, mercury, nickel, zinc during exposure 48,72 four different Hardness muchsmaller upon mercury than otherheavy tested. results indicate that Cu, Cd, Hg Zninduced autotomy caudal region mucus production. It isconcluded parameters should be considered inestablishing appropriate quality criteria standards forthe protection aquatic fauna flora, ultimately human health.