RESPONSE OF FRESHWATER SNAIL (Angulyagra polyzonata) AS WATER BIOMARKER BY HEAVY METALS (Cd, Cu, Zn, Pb)

Metals toxicity testing of freshwater snail (Angulyagra polyzonata) was carried out in laboratory by artificially exposing to metals Cd, Cu, Zn, and Pb less than 48 hours test. The results showed that toxic levels of metals increases in the order: Zn2+<Pb2+<Cd2+<Cu2+. In particular, the highest toxicity level was observed by exposing to Cu2+ with effect concentrations (EC50) between 0.17 and 0.21 ppm; lethal concentration (LC50) was 2.937 ppm. Other metals (in toxicity order of Cd, Pb, and Zn) in the National Technical Regulation (NTR 08:2008/MONRE) did not affect seriously to snail. The maximum acceptable concentration of the metals for snail in exposure for 48 or 24 hours was Cd: 0018 - 0.021 ppm; Cu: 0.0008 - 0.0012 ppm; Zn: 0071 - 0.082 ppm and Pb: 0.134 - 0.276 ppm.+.>