- Air pollution caused by hazardous PM2.5 fine particulate matter led to the death of 54,000 people in Delhi last year where pollution levels remained almost six times above the prescribed WHO limits.
- PM2.5 refers to fine particulate matter smaller than 2.5 micrometres in diameter. Exposure to PM2.5 is considered the most important environmental risk factor for deaths globally, and was attributed to 4.2 million premature deaths in 2015.
- Globally, approximate 160,000 deaths have been attributed to PM2.5 air pollution in the five most populous cities of Delhi (30 million), Mexico City (22 million), Sao Paulo (22 million).