Spike in pollution levels may raise death rates in cities with cleaner air, says study

• Spike in air pollution in Indian cities that have cleaner air may raise death rates higher than in cities that have higher pollution loads.

Highlights:

• The same increase in air pollution in, say, Bengaluru, can raise death rates more than in Delhi, which has much higher background levels of air pollution.
• Overall, however, cities that had high pollution loads saw a greater fraction of annual deaths attributable to air pollution, with 11.5% of Delhi’s annual deaths attributable to air pollution, and 4.8% in Bengaluru.
• The latter’s population had 30% the exposure to daily air pollution that an average Delhi resident is subjected to.
• The scientists analysed pollution and death registry data from Ahmedabad, Bengaluru, Chennai, Delhi, Hyderabad, Kolkata, Mumbai, Pune, Shimla, and Varanasi.
• Nearly 30,000 deaths, or 7.2% of the annual deaths in the 10 cities, were due to short-term PM 2.5.
• The total daily deaths in these cities rose by 1.42% for every 10 microgram per cubic metre increase in the average PM 2.5 exposure over a two-day period, the study found.

Prelims Takeaway

• Air Pollution