Bioaccumulation of cadmium in gills and muscles of shellfsh from Pulicat lake, Tamil Nadu, India
Authors: Kalyanasundaram Dhinamala, Munuswamy Pushpalatha, Mohamed Meeran, Subramanian Arivoli, Samuel Tennyson, Rajasingh Raveen
Number of views: 34
Objective: To evaluate the presence of heavy metal cadmium in six species of shellfish at
Pulicat Lake, Tamil Nadu, India.
Methods: Six species of shellfish, Fenneropenaeus indicus, Fenneropenaeus monodon,
Fenneropenaeus semisulcatus, Scylla serrata, Clibanarius longitarsus and Meretrix casta (M.
casta) in Pulicat lake, Tamil Nadu, India were analysed for the presence of cadmium in the
gills and muscles from January 2011 to December 2012.
Results: The results showed seasonal variations in the uptake of cadmium. Very high
accumulation of cadmium was found in the gills and muscles of M. casta during post monsoon,
summer, premonsoon and monsoon. The corresponding values of cadmium present in the gills
of M. casta were 1.59, 1.56, 1.48 and 1.46 µg/g in 2011 and 1.16, 1.25, 1.15 and 1.14 µg/g in
2012. Whereas for muscles, they were 1.14, 0.11, 0.96 and 0.80 µg/g in 2011 and 0.49, 0.34,
1.05 and 1.20 µg/g in 2012.
Conclusion: The results of the present study has shown that the accumulation of cadmium
found in the gills and muscles were high in M. casta when compared to other species of
shellfish. Thus, the consumption of the shellfish is safe, but does not exclude bioaccumulation
risk in their meat. This present study has highlighted the need for estuarine biomonitoring
to avoid possible contamination of shellfish and its consumers. The overall scenario of the
shellfish accumulating high levels of cadmium indicates that the Pulicat lake is polluted
with undesirable elements and the risk of consuming the meat of shellfish by man and other
carnivores may lead to their toxicity. Stringent control measures are necessary to control the
pollution of this precious lake to reduce the bioaccumulation of toxic metals in organisms