Key Highlights of the World Air Quality Report 2023

Context:

India has been identified as the world’s third most polluted country, as per the World Air Quality Report 2023 by Swiss organisation IQAir.

Relevance:

GS III: Environment and Ecology

Dimensions of the Article:

1. Key Highlights of the World Air Quality Report 2023
2. WHO Air Quality Guidelines
3. Particulate Matter (PM)

Key Highlights of the World Air Quality Report 2023:

• India’s Pollution Ranking: India is ranked as the world’s third most polluted country, with an average annual PM2.5 concentration of 54.4 micrograms per cubic meter.
• Bangladesh and Pakistan’s Pollution Levels: Both Bangladesh and Pakistan surpassed India in pollution levels, becoming the most and second most polluted countries, respectively.
• Top Polluted Cities: Nine out of the top 10 most polluted cities globally are located in India.
• Air Quality in Delhi: Delhi emerged as the world’s most polluted capital city for the fourth consecutive time.
• Pollution in Begusarai: Begusarai in Bihar is identified as the world’s most polluted metropolitan area, recording an average PM2.5 concentration of 118.9 micrograms per cubic meter.
• High Exposure Levels: Approximately 136 million Indians, which is 96% of the population, face PM2.5 concentrations that are seven times higher than the World Health Organization’s recommended levels.
• City Pollution Levels: Over 66% of Indian cities reported annual average PM2.5 concentrations higher than 35 micrograms per cubic meter.
• Health Implications: PM2.5 pollution, primarily from burning fossil fuels, is associated with increased risks of heart attack, stroke, oxidative stress, asthma, cancer, and mental health complications.
• Countries Meeting WHO Guidelines: Only seven countries met the WHO annual PM2.5 guideline of 5 µg/m3 or less, which includes Australia, Estonia, Finland, Grenada, Iceland, Mauritius, and New Zealand.
• Air Quality Data in Africa: Africa remains the most underrepresented continent in air quality data, with a third of its population lacking access to such information.
• Progress in Pollution Reduction: Some countries, like China and Chile, reported reductions in PM2.5 pollution levels, indicating efforts to combat air pollution.
• Global Impact of Air Pollution: Air pollution contributes to approximately seven million premature deaths annually worldwide, accounting for about one in every nine deaths.
• Health Risks: Exposure to elevated levels of fine particles can impair cognitive development in children, exacerbate existing illnesses such as diabetes, and lead to mental health issues.

WHO Air Quality Guidelines:

Pollutants Covered:

• The World Health Organization (WHO) updates its air quality guidelines to protect public health from the detrimental effects of air pollution. The latest revision was in 2021, succeeding the 2005 guidelines.
• The guidelines encompass both particulate matter (PM) and gaseous pollutants. These include:
  • PM2.5 and PM10
  • Ozone (O3)
  • Nitrogen dioxide (NO2)
  • Sulfur dioxide (SO2)
  • Carbon monoxide (CO)

Particulate Matter (PM):

• Definition: Particulate matter comprises tiny particles and liquid droplets suspended in the air. This mixture consists of various sizes and is composed of numerous compounds.
• PM10 (Coarse Particles): These are particles with a diameter of 10 micrometres or less.
• PM2.5 (Fine Particles): These are particles with a diameter of 2.5 micrometres or less.

-Source: The Hindu