Detection of Cadmium Acute Toxicity in New reported Species Crassostrea sp.

Heavy metals in high concentrations in the environment, is caused serious damage in metabolic, physiologic and structural organisms. Cadmium as the second most toxic metal in marine environments is considered. Bivalvia especially oysters are Suitable bioindicators due to its high filtration rates, immobility and lack of regulatory systems for removing of heavy metals. Crassostrea sp. is new species has wide distribution in Bandar Emam Khomeini. This species is the best for using toxicity testing to determine the effects of heavy metal pollutants in the environment. The aim this study is determination of Medium Lethal Concentration (LC5096h), Maximum Allowable Toxicant Concentration (MATC) and Lowest Observed Effect Concentration (LOEC) of Cadmium in Crassostrea sp. oyster. Fifty oysters (5.3±0.76 gr) were collected from Bandar Emam Khomaini and transported to laboratory. After Acclimatization (for 7 days), the 96-h LC50 tests were conducted (static Method) according to standard instruction O.E.C.D. The 96 h LC50, NOEC and LOEC were 15.8, 1.58 and 2.9 mg/l respectively. The LC50 correlation whit in 24 h and 96 h were showed Linear equation y=-0.4225x+54.35.