PM 2.5 raises risk of heart disease, obesity

According to new research findings, high doses of PM 2.5 particulate matter pollution, especially in cities, not only increases the risk of heart disease but also contribute to obesity and low cognitive ability.

Much of the new findings were considered by medical professionals and scientists during a dialogue — Air Pollution and Health — at the Indian Institute of Science on Thursday.

6.5 million deaths

Dr Sundeep Salvi, director of the Chest Research Foundation, Pune, pointed out that air pollution kills an estimated 6.5 million people worldwide each year — three times more than HIV, tuberculosis and malaria put together, with 2.51 million of those deaths in India.

“People don’t understand the full extent of the damage caused by air pollution,” Dr Salvi said. “Studies have shown that for every litre of fuel burnt by a car, people also end up consuming 1,700 litres of oxygen or 8,500 litres of air. This is an outlandishly high amount considering that the average person requires 10,000 litres of oxygen every day.”

In addition to excess oxygen consumption, a study by Chinese scientists last year discovered that air pollution affects the mental capacity of people as measured by verbal and mathematical test scores, explained Dr Salvi, adding that pollution is also linked to obesity. Tests have shown the children of mothers living in polluted environments are heavier, with a higher level of cholesterol related to metabolism, he added.

Lead pollution threat

Paediatricians expressed concern for schoolchildren over the new research findings. Dr Karthik Nagesh, chief of paediatrics and neonatologist at Manipal Hospitals, explained that lead-based pollution has an especially potent effect on children.

“Many children go to school in open-air vehicles and you have all these heavy industrial vehicles releasing lead-tainted exhaust right into their faces. Lead causes cognitive problems. In addition, sulphur-dioxide and nitrogen-dioxide, which emanate from industrial sources, can also cause chronic lung disease and affect cognition,” Dr Nagesh said.

While most people consider ambient or external air pollution as the primary culprit for the rise in particulate matter levels in the country, new research indicates that indoor air pollution is also a significant factor affecting health.

“What people need to consider is internal pollution is equally damaging as ambient pollution,” Dr Salvi added, explaining that a single mosquito coil produces as much smoke as 100 cigarettes while a single dhoop incense stick produces five times the air pollution compared to a mosquito coil or repellent.