Ref ID : 4985

B.S. Khangarot and Rashmi S. Rathore; Protective Action of 24 Amino Acids on the toxicity of Copper to a Freshwater Tubificid worm Tubifex tubifex Muller. Water,Air,and Soil Pollution 157:53-63, 2004
Reprint : In File
Notes : The protective action of 24 amino acids on the acute toxicity of copper to a freshwater tubificid worm, Tubifex tubifex is investigated. The results showed that the toxicity of copper to T. tubifex decreased with the addition of all the amino acid tested concentrations. The acute toxicity closely related to total copper concentrations. One hundred percent mortality occurred at 0.32 mg/l of Cu alone and in higher Cu concentrations during the 96 hr of exposure. A dose-dependent toxicity decrease in Cu + amino acid concentration was observed as evidence by a decrease in percent mortality. We found that the LC50 of copper to T. tubifex increased (i.e., toxicity decreased) linearly with increasing each amino acid concentrations from 2 mM to 20 mM. Our results indicate the presence of histidine, leucine, and aspartic acid significantly neutralize the toxicity of Cu, which suggest that copper binds more strongly with these amino acids. The 96 h LC50 value was 0.084 mg/l for Cu alone, while the LC50's with amino acids ranged from 0.164 to 11.80 mg/l of Cu, indicating a 1.95 to 141-fold decrease in acute toxicity of copper. These studies suggest that the Cu toxicity in aquatic organisms can be overcome by amino acids.