Table of Contents
Advances in Toxicology
Volume 2014, Article ID 251812, 7 pages
Research Article

Genotoxicity Study with Special Reference to Comet Test in the Blood Cells of Workers Exposed to Sewage Water

1Institute of Hematology and Transfusion Medicine, Medical College, 88 College Street, Kolkata 700073, India
2Department of Environmental Science, University of Calcutta, 35 Ballygunge Circular Road, Kolkata 700019, India
3Netaji Nagar College for Women, 170/13/1N.S.C Bose Road, Regent Estate, Kolkata 700092, India
4UGC-DAE Consortium for Scientific Research, III/LB-8, Salt Lake, Kolkata, West Bengal 700098, India
5Department of Biochemistry, University of Calcutta, 35 Ballygunge Circular Road, Kolkata 700019, India
6Presidency University, 87/1 College Street, Kolkata 700073, India

Received 28 April 2014; Revised 8 July 2014; Accepted 12 October 2014; Published 23 November 2014

Academic Editor: Rosa Busquets

Copyright © 2014 Rajlaxmi Basu et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Awareness among sewage workers to occupational exposure is growing slowly in many developing countries. Lead (Pb) and cadmium (Cd) are present in sewage water and workers are exposed to these metals as a result of unprotected handling. These heavy metals exposures are responsible for DNA damage and lowering blood total iron (Fe) concentration. Zinc (Zn) is an element for promoting metallothionine expression and binds the free Cd. The total suspended solids (TSS), total dissolved solids (TDS), Pb, and Cd were estimated in sewage water. The whole blood Zn and Fe concentration and Pd and Cd were also estimated. Genotoxicity as indicated by DNA damage was studied by comet assay. It was observed that there were significant differences () of Pb and Cd concentration in blood for the sewage workers when compared with control population. DNA damage was also observed to be significantly () higher in the exposed groups but their blood Fe concentration was significantly lower, which may be the reason for their tendency for retention of blood Cd and make them more susceptible. This study also indicated that aged workers had higher blood Zn concentrations as compared to the younger (working < 20 years) workers. This may indicate a possible adaptive response. The present study proposes that younger (working < 20 years) group is more susceptible as compared to aged group (working > 20 years).