Acute Toxicity of Selected Heavy Metals to Mangrove Oyster Crassostrea rhizophorae

Abstract

The lethal concentration (LC50) values of four heavy metals for the mangrove oyster Crassostrea rhizophorae were determined by the static bioassays. The test animals were collected from Laguna Grande, Gulf of Cariaco, Sucre State, Venezuela, and were acclimated in the laboratory condition for two weeks prior to bioassays. Acclimation temperature and salinity were 23.5°C and 36‰, respectively. The 216-h LC50 values (mg/l) determined by probability-logarithm transformation were 0.6 for cadmium (II), less than 1 for copper (II), 7 for chromium (VI), and 16 for zinc (II). The above indicates that the order of toxicities of metals tested to the mangrove oyster is cadmium>copper>chromium>zinc. © 1980, The Japanese Society of Fisheries Science. All rights reserved.