UPSC CURRENT AFFAIRS – 17 March 2025

Home UPSC Current Affairs Byrnihat: Most polluted city in the world

Byrnihat: Most polluted city in the world

Why in News:

Byrnihat, located on the Meghalaya-Assam border, has been identified as the most polluted city in the world due to a combination of industrial emissions, weak regulatory enforcement, and vehicular pollution.

Background:

According to the World Air Quality Report 2024, published by IQAir, Byrnihat, a town on the Assam-Meghalaya border, has been ranked as the most polluted city in the world.
The report states that the town recorded an annual average PM2.5 concentration of 128.2 µg/m³, far exceeding the World Health Organization’s (WHO) guideline of 5 µg/m³.
Byrnihat was also previously identified as India’s most polluted city in January 2024 by the Centre for Research on Energy and Clean Air (CREA), based on monthly average PM2.5 levels.
The worsening air quality in Byrnihat raises concerns about industrial pollution, vehicular emissions, and topographical influences that trap pollutants in the region.

Reasons for Severe Air Pollution in Byrnihat

Industrial Pollution :
Byrnihat, located 20 km from Guwahati and 65 km from Shillong, has developed into a major industrial hub over the years. It hosts several industries, many of which contribute significantly to air pollution.
- The industries in Byrnihat are located in both Meghalaya and Assam.
- In Meghalaya, they are concentrated in the Byrnihat Export Promotion Industrial Park (EPIP).
- In Assam, they are located in Tamulikuchi, Kamrup Metropolitan district, along the national highway.

The Meghalaya State Action Plan for Prevention and Control of Air Pollution (2024) reported 39 industrial units in Assam and 41 in Meghalaya in Byrnihat.

- 20 units in Assam and 5 in Meghalaya belong to the red category.
- 15 units in Assam and 22 in Meghalaya belong to the orange category.

The proximity of these industries to coal reserves and water sources like the Umtru River has facilitated their growth, but has also significantly contributed to air pollution.

Non-Compliance with Pollution Control Norms: Authorities have found widespread violations of pollution control norms in Byrnihat.
- In January-February 2024, the Meghalaya Pollution Control Board conducted surprise inspections and:
  - Served closure notices to seven industries.
  - Imposed environmental penalties on two units.
- Violations included:
  - Excessive emissions due to non-functional pollution control devices.
  - Ineffective emission reduction mechanisms.
  - Failure to transmit online pollution data to regulators.

The Assam Pollution Control Board has also identified violations by industries failing to operate pollution control equipment to reduce operational costs.

Vehicular Emissions and Traffic Congestion: Byrnihat serves as an important transit hub for vehicles transporting goods to and from industrial areas.
- Heavy-duty diesel vehicles frequently idle in traffic congestion, releasing large amounts of PM2.5, PM10, and sulfur dioxide (SO₂).
- Loading and unloading activities contribute to additional dust pollution.
- Many of these vehicles fail to comply with emission norms, exacerbating air quality issues.

Topographical Factors and Meteorological Conditions: Byrnihat’s geographical location and topography contribute significantly to its air pollution crisis.
- The region is situated in a low-altitude basin (60 metres above sea level), surrounded by hills on both sides.
- This creates a “valley-and-basin effect”, where:
  - Wind speed is significantly reduced.
  - Pollutants remain trapped instead of dispersing into the atmosphere.
- The presence of unpaved roads further aggravates road dust pollution, as observed in a CSIR-NEERI survey (2022-23).

These natural conditions worsen pollution levels and prevent the effective dilution of airborne pollutants.

Government Response and Challenges

Regulatory Actions: The Meghalaya and Assam Pollution Control Boards have initiated actions to address air pollution in Byrnihat. However, challenges remain due to:

- Industrial resistance to adopting cleaner technology, citing high operational costs.
- Weak enforcement of pollution norms, allowing non-compliant industries to continue operations.
- Lack of proper waste and emissions monitoring systems.

Need for Comprehensive Air Pollution Control Measures

- Stronger enforcement of pollution control norms.
- Introduction of stricter emission caps for industrial units.
- Shifting towards cleaner fuels and phasing out outdated industrial processes.
- Better road management to reduce congestion and vehicular emissions.

What is Air Pollution?

Air pollution refers to the presence of harmful solids, liquids, gases, noise, or radioactive radiation in the atmosphere that negatively impact human health, living organisms, property, and environmental processes.

Pollutants can be natural or human-made, originating from sources such as:

Industrial processes (factories, power plants)
Vehicle emissions (cars, trucks, airplanes)
Agricultural activities (burning of crop residue, use of fertilizers)
Natural events (wildfires, volcanic eruptions, dust storms)

Air Quality Index (AQI)

The Air Quality Index (AQI) provides a simple and easy-to-understand measure of air pollution levels, allowing the general public to assess the quality of air in their surroundings.

Key Features of AQI

Launched in 2014 under the Swachh Bharat Mission.
Developed by the Central Pollution Control Board (CPCB).
Follows the concept of “One Number – One Colour – One Description” for easy understanding.
Covers eight major pollutants:
1. PM10 (Particulate Matter ≤10μm)
2. PM2.5 (Particulate Matter ≤2.5μm)
3. NO₂ (Nitrogen Dioxide)
4. SO₂ (Sulphur Dioxide)
5. CO (Carbon Monoxide)
6. O₃ (Ozone)
7. NH₃ (Ammonia)
8. Pb (Lead)

AQI Categories and Health Impacts

AQI Category	AQI Range	Health Impact
Good	0-50	Minimal impact
Satisfactory	51-100	Minor breathing discomfort for sensitive individuals
Moderately Polluted	101-200	Breathing discomfort for people with lung diseases, children, and elderly
Poor	201-300	Discomfort on prolonged exposure, risk for heart patients
Very Poor	301-400	Respiratory illness for prolonged exposure, especially for heart/lung patients
Severe	401-500	Severe impact on healthy individuals, serious risk for people with lung/heart diseases

National Air Quality Monitoring Programme (NAMP)

The Central Pollution Control Board (CPCB) operates the National Air Quality Monitoring Programme (NAMP) to track air pollution across India.

Key Features of NAMP

Covers 800+ monitoring stations across 344 cities/towns in 28 states and 6 Union Territories.
Monitors four key pollutants:
- Sulphur Dioxide (SO₂)
- Nitrogen Oxides (NO₂)
- PM10 (Particulate Matter ≤10μm)
- PM2.5 (Particulate Matter ≤2.5μm)
Also monitors meteorological factors like wind speed, humidity, and temperature to assess pollution patterns.
Helps in identifying non-attainment cities (where air quality consistently exceeds permissible limits).