- Special Pages
Kolkata: Scientists in Kolkata have developed a new high-precision technique to detect arsenic in water, a toxic substance widespread in the groundwater of India and Bangladesh that on long-term exposure is capable of causing skin cancer.
According to the WHO, natural arsenic contamination is a cause for concern in many countries, including Argentina, Bangladesh, Chile, China, India, Mexico, Thailand and the United States.
The new method developed by the scientists enables high-precision detection of arsenic through tiny gold clusters that signal its presence in water by emitting light (a phenomenon called fluorescence).
“The ultra-sensitive sensors synthesised by us were in the form of gold clusters that signal the presence of arsenic in water by emitting more light or fluorescence when in contact with the toxic arsenic in water.
“It even detected arsenic in presence of other toxic metal ions,” Arindam Banerjee of the Department of Biological Chemistry of the Indian Association for the Cultivation of Science, said.
Chandra Bhushan, deputy director general of the Centre for Science and Environment, New Delhi, said arsenic poisoning in India was a widespread phenomenon which needed monitoring techniques as well as methods for removal of the toxic substance.
“Arsenic poisoning of groundwater is widespread in Uttar Pradesh, Bihar and West Bengal. Even our neighbour Bangladesh faces the same problem,” Bhushan said.
The unique feature of the new monitoring technique is that it can roughly indicate the extent of arsenic contamination.
“The more the light emitted, the greater the quantity of arsenic present,” Banerjee added.