Rampant garbage burning along the highways in Mumbai, Thane, Raigad is posing a huge threat to people's health. A survey by the Awaaz Foundation to measure PM2.5 at some of these sites, has found that pollution levels had a direct co-relation with the size of the garbage dump being burnt. A dump at Bhiwandi showed the highest level of PM2.5.

Air pollution is measured by quantifying total suspended Particulate Matter identified by the size of the particles. PM2.5 are minute particles of 2.5 micrograms or smaller. These particles contain a mixture of solids and liquids and include acids such as sulfates and nitrates, ammonium, carbon and mineral dust. The PM2.5 recorded at Bhiwandi was 612µ/mg3 (µ - microgram, mg3 - per cubic meter) while the permissible amount is 20µ/mg3.