Indian Journal of Science and Technology

Abstract

A study was carried out to investigate the contamination of heavy metals in muscle and intestine tissue in 7 fish species and 1 prawn species, caught at upstream and downstream points along the Savitri River in the Raigad district of Maharashtra. The river course has a discharge point in which the Common Effluent Treatment Plant (CETP) discharges its treated effluent. Water analysis was carried out from 10 different locations in the upstream and downstream of the river from the discharge point. The common fish species available in the river course were collected and toxicity tests were carried out for the muscle and intestine samples for 3 metals: lead (Pb), cadmium (Cd) and mercury (Hg) by Atomic Absorption Spectroscopy (AAS). The results showed that lower metal values were recorded in the water than fish organs. The concentrations of metals (mg lt-1) in water were below the levels recommended by the Maharashtra Pollution Control Board for drinking, except for Pb (0.31±0.02). The highest concentration (mg lit-1) of all heavy metals was recorded upstream, in the intestine of Etroplus suratensis (3.42±0.07 for Pb) while the lowest was recorded downstream, in the muscle of Cynoglossus macrolepidotus (0.07±0.01 for Hg). There were significant differences (P<0.05) between mean concentrations in muscle and intestine as compared to water samples at both upstream and downstream sampling points. However, no significant differences (P>0.05) were recorded in mean concentrations between muscle and intestine in species, except for Cd and Hg levels in Liza tade, caught upstream and Cd level in Machrobrachium malcolmsonni, caught downstream (P<0.05). Overall results indicated that fish organs were slightly contaminated by heavy metals, mainly by Pb, but did not exceed the levels recommended by the Indian Food Safety & Standards regulation (FSSAI), 2011. Keywords: Heavy metal toxicity, CETP, fish, muscle, intestine