Air Quality and Health in Cities: Delhi, Kolkata, Mumbai among world’s top 20 most polluted cities

Source: The post is based on the article “Delhi, Kolkata, Mumbai among world’s top 20 most polluted cities” published in Indian Express on 17th August 2022.

What is the News?

The report titled ‘Air Quality and Health in Cities’ has been published by the State of Global Air.

Note: State of Global Air is a collaboration between the US-based Health Effects Institute (HEI) and the Institute for Health Metrics and Evaluation’s Global Burden of Disease Project. It is a research and outreach initiative to provide reliable, meaningful information about the air quality around the world.

What is the Air Quality and Health in Cities report?

Purpose: To analyze air pollution and global health effects for more than 7,000 cities around the world.

The report focuses on two of the most harmful pollutants; fine particulate matter (PM2.5) and nitrogen dioxide (NO2).

What are the key findings of the report?

PM 2.5 deaths: In 2019, 1.7 million deaths linked to PM2.5 exposure occurred in 7,239 cities with cities in Asia, Africa, and Eastern and Central Europe seeing the greatest health impacts.

– Beijing had the largest disease burden associated with a PM 2.5-related illness, with 124 attributable fatalities per 100,000 persons.

Delhi came in 6th, with 106 deaths per 100,000 and Kolkata at 8th.

PM 2.5 levels: Delhi and Kolkata are ranked first and second in the list of top 10 most polluted cities when PM 2.5 levels were compared.

NO2 Levels: No Indian city appeared in the list of top 10 or even top 20 polluted cities when NO2 levels were compared. This list saw Shanghai at the top with an average annual exposure of 41 µg/m3.

Note: NO2 comes mainly from the burning of fuels in older vehicles, power plants, industrial facilities and residential cooking and heating.

– As city residents tend to live closer to busy roads with dense traffic, they are often exposed to higher NO2 pollution than residents of rural areas.

Other Key findings: Only 117 nations currently have ground-level monitoring systems to track PM 2.5, and only 74 nations are monitoring NO2 levels.

– In 2019, exposure to pollutants in 86% of the more than 7,000 cities exceeded WHO’s standard, therefore, impacting around 2.6 billion people.

What are the recommendations of the report?

Leverage the expanding air quality monitoring toolbox:  Efforts should be made to expand ground monitoring of air quality to improve the accuracy of estimates of Pollutant levels and understanding of local air quality trends.

– However, in addition to setting up monitors, it is important to invest in resources for calibration and maintenance to ensure the quality of data from these monitors.

Digitize health records: Data on the burden of air pollution on health are vital for assessing the effectiveness of interventions, both in terms of public health benefits and economic impact.

– It is important to collect city-level health data consistently and systematically and make them accessible to researchers. This can help researchers conduct more accurate and local analyses that inform communities and policymakers.