So far millions of Indians were drinking arsenic dissolved in groundwater. But now many could also be breathing this toxic substance too.
A study by two professors and a student of the civil engineering department of Jadavpur University in Kolkata have stumbled upon arsenic particles – nearly two times the permissible limit prescribed by the Central Pollution Control Board (CPCB) -- suspended in the air in a locality in south Kolkata. The area is already known to be in the grip of arsenic ground water contamination.
Long-term exposure to high levels of this toxic element can lead to chronic arsenic poisoning (arsenicosis). It can affect the nervous system, kidney, heart and placenta of women among other organs.
“It can’t be an aberration, as all the samples collected over six months showed almost equal levels of arsenic. The air samples were tested at a lab accredited by the National Accreditation Board for Testing and Calibration Laboratories,” said Amit Dutta, associate professor and a member of the JU study team.
“This is the first time we have found arsenic particles in the ambient air. It seems to be an emerging pollutant in Kolkata and a matter of serious concern. More research is needed to confirm the finding and zero in on the source,” said Dutta.
According to CPCB guidelines, the permissible limits for arsenic in air is 6 nanograms per meter cube. But the quantity of arsenic found in all the 65 samples is more than 13 nanograms per meter cube.
The finding came to light earlier this week when it was mentioned in a report on Kolkata’s Air Quality, which was prepared after a series of roundtable talks organized by the US Consulate in Kolkata, Global Change Program of Jadavpur University and a city-based social enterprise Banglanatak dot com. The report would be handed over to the state government too.
“To our knowledge, there has been no study on presence of arsenic in the air in Indian cities,” Dutta added.
The team was analyzing 65 air samples collected between October 2014 and March 2015 from near the university campus gate for a completely different purpose. It was a part of master thesis. The experts, however, were flabbergasted when all the samples showed high levels of suspended arsenic particles – twice the permissible limit of 6 nanograms per cubic metre of air.
The area where Jadavpur University is located is a densely populated middle class residential area with an arterial road running past the gates of the campus. It is not an industrial area.
The samples also tested positive for Nickel – another metal which if inhaled in high doses could lead to several diseases including cancer. Nearly 50% of the samples showed that suspended nickel particles were present at least 1.5 – 2 times above the permissible limit of 20 nanograms per cubic metre of air (Central Pollution Control Board standards).
In 1983 Dipankar Chakraborti, a professor from the same university, first detected arsenic contamination of ground water in West Bengal. It had sent shock waves across the country. Even the government was initially reluctant to accept the results but had to accept it later on.
Speaking to HT, Dutta said that even though the exact source is yet to be ascertained but it could be coming from underground.
“Jadavpur area, from where the samples were collected, is known to be arsenic prone for several years now. We won’t be surprised if further research reveals that arsenic particles are coming from the underground water and then being released into the air as dust,” he said.
In that case it could have far reaching ramifications as around seven states including West Bengal, Jharkhand, Bihar and Assam among others are exposed to arsenic contaminated drinking water affecting more than 70 million people. Other countries are affected too.
“The reports were not made public as the samples were collected from just one place and we needed more confirmation. Besides this we need to test them in our own labs for which substantial funds are required. We now plan to take up further research,” said Dutta.