He is an environmental epidemiologist and his main area of research encompasses effect of local and global environment on human health including climate change and health, especially on infectious diseases air pollution and health epidemiology of neurodegenerative disorders and various issues on environmental and occupational health, including humidifier disinfectants and oil spill and health. His main area of research is as below.
1. Health effect of air pollution
2. Health effect of climate change
3. Prediction of infectious diseases from climate variability and other environmental factors
4. Epidemiology of neurodegenerative disorders (currently not active)