New analysis from Smart Air finds that 2018 was a good year for air quality for India’s major cities. Air quality was flat or down in three of five cities—Delhi, Hyderabad, and Chennai.
Air quality worsened in Mumbai too. Particulate levels rose 15% year over year in Mumbai.
Analysis by month shows that Mumbai’s worsening air quality came mostly from unusually polluted summer months.
In Kolkata, 2018 air quality was worse mostly in the winter months.
Microscopic Particles in the Air
The analysis is based on PM2.5 pollution, particles smaller than 2.5 microns in diameter that can penetrate deep into the lungs and even enter the bloodstream. Studies have shown that PM2.5 raises blood pressure, inflammation, and rates of heart attacks and strokes.
The data comes from the US Embassy and consulates in India’s major cities. This data is open for researchers, although it has limitations. It comes from only one pollution sensor in each city, and pollution can vary between neighborhoods.
Despite the harms of PM2.5, studies have found that wearing masks prevents physiological harm to the body. In addition, placebo-controlled studies of air purifiers have found that removing particulate in the home has positive effects on blood pressure, inflammation, and immune response.
Smart Air provides empirically backed, no-nonsense purifiers and masks to help air-breathers protect themselves and their family. Smart Air is a certified B Corp founded to publicize the simple science behind air purifiers and masks, thereby lowering the cost of breathing clean air.
Thomas is an Associate Professor of Behavior Science at the University of Chicago Booth School of Business and the founder of Smart Air, a social enterprise to help people across the world breathe clean air without shelling out thousands of dollars for expensive purifiers.