University research finds arsenic in Vapi effluent treatment plant

SPU chanced upon these bacterial strains while

researching on bioremediation of arsenic. Bioremediation relates to the use

of bacteria in removing

arsenic present in drinking or polluted water.

B R Naidu,the CPCB regional director of Gujarat,expressed ignorance about the issue. “Arsenic is not found in its natural form in Gujarat. Arsenic contamination of groundwater has been detected in West Bengal and Bangladesh,but we have not done any similar study in Gujarat,” he said.

Naidu added that the SPU finding,published in the Journal of Hazardous Materials,could point to two possibilities: “There could be deep drilling of groundwater,and it could also be due to dumping of arsenic content by industries at the site.”

Arsenic ranks first in the US government’s Priority List of Hazardous Substances,because of both its toxicity and prevalence in the environment. It is a

carcinogen and considered

a grave public health problem worldwide .

Prof Kalia said: “My work is related to bioremediation of arsenic found in drinking water of some states. It has been well documented that bacteria has a detoxifying mechanism against arsenic toxicity. In general,metals in contaminated water are removed by methods such as chemical precipitation,ion exchange or adsorption. These methods have disadvantages,which include high costs.” She added the bacterial cells capable of removing arsenic from their surroundings could be ideal candidates for bioremediation. “It could be used as an alternative or to supplement existing physicochemical methods of arsenic removal.”

Prof Kalia,who has been working on this issue for many years,found arsenic hyper-tolerant bacterial strains at Vapi CETP isolates,which can tolerate 400 micromoles of arsenic with high arsenic accumulation capacities.

She said bacteria at the Vapi CETP have mutated themselves to tolerate this level of arsenic. She refused to comment on pollution saying: “It is not my area of research. We tried to find metal hypertolerant and metal accumulating bacteria,but this bacterial strain is the best suited for bioremediation of arsenic in comparison to other isolates found in other areas.”