Finding the Cause

Fulbright-Kalam Climate Fellow Chinmoy Sarkar is focusing his postdoctoral research at the University of California, Irvine, on the causes and impact of air pollution, especially in India.

In today’s world, air pollution has become a major cause of concern due to its grave impact on the environment and human health. Long- and short-term exposure to air pollutants can have various toxicological effects on us, including respiratory and cardiovascular diseases, neuropsychiatric complications, skin diseases and even chronic diseases like cancer. Air pollution is also a risk factor in the incidence and progression of diseases like asthma and lung cancer. Several reports have revealed the association between exposure to poor-quality air and increasing rate of morbidity and mortality.

This relation between air pollution and human health is the postdoctoral research area of Indian scientist Chinmoy Sarkar at the University of California, Irvine (UC Irvine).

In 2017, Sarkar received the Fulbright-Kalam Climate Fellowship, a one-year exchange program funded jointly by the governments of the United States and India, for his research at the university. The fellowship is administered by the United States-India Educational Foundation (USIEF) on behalf of both the governments.

Sarkar’s focus is on learning methods to determine the exact sources of air pollution. This is crucial for countries like India which are urgently trying to improve their worsening air quality. The research should help them develop more effective policies, depending on the pollution source-vehicles, industry, farming or others.

Excerpts from an interview.


In 2017, the Delhi government introduced a number of emergency measures, including school closures and traffic restrictions, to combat air pollution in the region. Why has the problem gotten so bad and what role does scientific research have to play?

Unlike a number of other Indian mega-cities, which are on the coast where ocean breezes vent the pollution, Delhi is inland and surrounded by other cities. On bad days, when you go outside, you feel a burning sensation in your eyes. The heavy smog reduces visibility, causes accidents and contributes to respiratory and lung diseases. Chinese cities have a similar problem. But, China began acting [to combat the issue] 15 to 20 years ago, so the situation is getting better. India started taking action two to three years ago. It takes time.

If you want to address the problem, you need to focus more research on identifying the sources of air pollution. There are so many complex sources of pollution in India. This includes biomass burning, industry and vehicles. But we don’t know which other sources are causing pollution. Once the research is done, we can take measures to resolve the problem. Maybe, this will include restricting vehicles; maybe not.


What do you suspect your research will point to as some of the major causes of the severe air pollution in Indian cities?

I think, it will probably point to both biomass burning and industry. Small farmers across India burn their crop residue before planting new crops, contributing to air pollution. The government has already tried to restrict this practice, but it is very hard to control, since it is the easiest way for farmers to prepare to plant the next crop. However, there are solutions.

Crop scientists in India are developing new techniques, including the “happy seeder.” This is a tractor-mounted machine that cuts and lifts rice straw, sows wheat into the bare soil, and deposits the straw over the sown area as mulch. The happy seeder could provide an alternative to allow farmers to stop burning their crop residue.


What are expectations from your research at University of California, Irvine?

I earned my Ph.D. in 2016 in atmospheric science from the Indian Institute of Science Education and Research in Mohali, Punjab. Before I came to the United States, I thought air pollution was caused by two or three things. Now, I’ve understood there are very complex reactions in the atmosphere, and there can be many more causes.

I’ve come to the U.S. to understand how scientists work in a more developed nation, and to build collaborations. My supervisor at UC Irvine, Alex Guenther, is a leading expert on the use of mass spectrometry to study air pollution. I’m working closely with him. Mass spectrometers can detect hundreds of compounds in an air sample, which can help us identify where the pollution came from. But they cost tens of thousands of dollars.

One of my dreams is to go back [to India] and develop low-cost, portable mass-spectrometers there. They might be able to only measure 20 or 30 compounds, but they would be much easier for Indian scientists to afford and use in the field. What I learn here, I’d like to implement in Indian cities.


Tell us about your experience of conducting research at University of California, Irvine?

It’s a very good university, and it gives students much more freedom to think and innovate. The faculty are very supportive; you can reach out to them any time. When I return home, I’d like to help students learn to do their own research in more productive ways.

Burton Bollag is a freelance journalist living in Washington, D.C.