Mumbai's Air Quality Was 9 times Above WHO Limit In 2021

According to a latest survey, the air quality in Mumbai recorded in 2021 was nearly nine times above the World Health Organisation (WHO) limit.

IQAir’s 2021 World Air Quality Report stated that Mumbai had recorded Particulate Matter (PM) 2.5 annual average of 46.4 microgram/cubic metre.

Prior to that, the PM 2.5 annual average had worsened in Mumbai. It was 41.3 µg/m3 in 2020 and 45.3 µg/m3 in 2019, the report further mentioned.

Additionally, it has also come to light that India is amongst the top five most polluted countries in 2021.

As per accounts, Mumbai witnessed high pollution levels in December and January and lowest air pollution levels are recorded post monsoon in September.

The Swiss group measures air quality levels based on the concentration of PM 2.5. is the first major global air quality report based on updated annual WHO air quality guideline for PM2.5.

The data reveals that January 2021 saw the highest monthly average concentration of PM 2.5 at 98.5 µg/m3. In comparison, the highest monthly average concentration of PM 2.5 was recorded in December 2020 at 70.6 µg/m3.

As traffic congestion was minimal during the 2020 COVID-19 lockdown, the lowest PM 2.5 monthly average was recorded in June at 15.9 µg/m3. In 2021, the lowest PM 2.5 monthly average was recorded in September at 15.3 µg/m3. PM 2.5 levels below 25 µg/m3 were recorded for four months of monsoon in 2021, the report stated.

Moreover, 48 per cent of India’s cities exceeded 50 µg/m3, or more than 10 times the WHO guideline. It added that no city in India has met the WHO air quality guideline of 5 µg/m3.

The new guidelines were released in September 2021 and cut the existing annual PM2.5 guideline value from 10 µg/m3 to 5 µg/m3. The goal of the guidelines is to assist policymakers around the world in crafting air quality legislation and emissions standards to levels that meaningfully reduce the public health risks posed by air pollution.

For those unversed, this report is generated exclusively from PM2.5 measurements obtained by ground-level monitoring stations.

Besides, PM2.5 concentrations, in micrograms per cubic meter (µg/m³) were selected as the standard metric for this report. PM2.5, particulate matter consisting of fine aerosol particles measuring 2.5 microns or smaller in diameter, is one of six routinely measured criteria air pollutants and is commonly accepted as the most harmful to human health due to its prevalence in the environment and broad range of health effects.