Assessment of Chiton lamyi mollusk as a biological indicator of heavy metals such as Cd, Cu, As and Hg in the coast of Chabahar Bay

Abstract

Mollusks are remarkably appropriate as a bio-indicator due to their wide geographical distribution, high abundance in benthic environments, selective absorption of certain ions and their motionless nature. Chiton, a mollusk of the phylum of Polyplacophora, and of its lamyi species is abundant in Chabahar Bay coastal rocks. Based on previous studies, this animal can be introduced as a potential indicator of Ecosystem Health; hence Chiton was chosen to be investigated rate of accumulation of metals, Cd, Cu, As and Hg in Chabahar Bay. After sampling four major stations, the samples were prepared and Cold Vapor Atomic Absorption apparatus were used for measurement of mercury and graphite furnace method was used for measuring other metals. Then, using the obtained data, bioaccumulation factor was calculated for each metal separately in the maximum amount of cadmium bioaccumulation factor at station 4 (Great sea) (136.34±0.02) and the lowest mercury at station 2 (Coast of Maritime University) (1.88±0.02), respectively. After statistical analysis of the results, it was found that Chiton can be introduced as a bio-indicator of the mentioned contaminants in the coast of Chabahar Bay.