Mercury pollution in the Sonbhadra district of Uttar Pradesh, India, and its health impacts

The Sonbhadra district in the Singrauli area of Uttar Pradesh, India, has many coal mines and thermal power plants and is a critically polluted area. Many residents of this area reported adverse health conditions which may be linked to metal pollution, especially of mercury investigated here.In May 2012, samples of water (23), soil (7), blood, hair, and nails from persons showing adverse health conditions selected at random were collected and analyzed for total mercury by atomic absorption spectrometry.Twenty percent drinking water samples contained mercury from 3 to 26g L-1 (3-26times the permissible limit). Soil samples had 0.5-10.1mg kg(-1) Hg.The average concentrations of mercury in human blood, hair, and nails were found to be 34g L-1, 7.4mg kg(-1), and 0.8mg kg(-1), respectively. Mercury concentrations in the blood of these persons were 45 and 28g L-1 on average in the case of men and women. This is much higher than the safe level of 5.8g L-1 set by the United States Environmental Protection Agency (USEPA).It was concluded that all residents of Sonbhadra sampled could be suffering from mercury toxicity as the area is polluted by Hg released from the coal-fired thermal power plants.