New Delhi: Delhi has emerged as the world's most polluted major city, with air quality reaching alarming levels just one day before the Hindu festival of Diwali. The worsening pollution has raised serious health concerns and prompted authorities to introduce emergency restrictions across the Indian capital and surrounding areas.
According to Swiss air quality monitoring organisation IQAir, Delhi recorded an Air Quality Index (AQI) reading of 581 at 10:35 a.m. Indian Standard Time on Saturday. The reading placed the Indian capital at the top of its global ranking of major cities. Lahore in neighbouring Pakistan ranked second, with an AQI of 285 at the same time.
India's Central Pollution Control Board (CPCB) recorded a separate AQI reading of 363 at 10 a.m. on Saturday. This placed Delhi in the very poor category under India's national air quality classification. On Friday, the city's AQI had reached 382, indicating continued poor air quality in the days leading up to the festival.
The two figures come from different monitoring systems and use different methods of calculating air quality. However, both indicate that Delhi is facing a serious pollution problem.
The situation has become particularly concerning as millions of people prepare to celebrate Diwali on Sunday, November 8. The festival, also known as the festival of lights, is traditionally celebrated with lamps, fireworks and family gatherings. Firecrackers release smoke and fine particles into the atmosphere, potentially adding to the pollution already affecting the city.
Authorities have responded by activating Stage III of the Graded Response Action Plan (GRAP), a set of emergency measures designed to control pollution across Delhi and the National Capital Region. The Commission for Air Quality Management introduced the restrictions on November 6 following a review of deteriorating air quality.
The measures include restrictions on construction and demolition activities, limits on certain older vehicles in Delhi and specified districts of the National Capital Region, and hybrid schooling arrangements for children up to Class 5. Certain essential construction and infrastructure projects are exempt from the restrictions.
Authorities have also advised government departments and private offices to consider allowing up to 50 per cent of their employees to work from home. Residents have been encouraged to avoid unnecessary travel as part of efforts to reduce vehicle emissions.
Weather conditions are expected to influence how pollution develops over the coming days. The Indian Institute of Tropical Meteorology has forecast that Delhi's air quality could enter the severe category between November 7 and 9. Limited wind movement and unfavourable atmospheric conditions could prevent pollutants from dispersing effectively.
Delhi's recurring winter pollution problem is linked to several sources. Vehicle emissions, industrial activity, construction dust and road dust contribute to the city's poor air quality. Smoke from agricultural residue burning in neighbouring agricultural regions, including Punjab and Haryana, also contributes to pollution during the post harvest period.
Although fireworks can worsen air pollution during Diwali, they are not the only cause of the current crisis. The combination of existing emissions, seasonal weather conditions and additional smoke from festival celebrations creates a greater challenge for the city.
The deteriorating air quality has raised concerns among health experts, particularly about its effects on children, older people and those with existing respiratory and heart conditions.
Fine particulate matter can travel deep into the lungs and contribute to breathing difficulties, airway inflammation and other health problems. Prolonged exposure to polluted air is also associated with an increased risk of respiratory and cardiovascular diseases.
Health experts have advised residents to limit unnecessary outdoor activities, avoid strenuous exercise outdoors and consider using properly fitted N95 or N99 masks when going outside. The use of suitable air purifiers indoors may also help reduce exposure to harmful particles.
However, these precautions can be difficult for people who work outdoors or live in crowded neighbourhoods where access to clean indoor air is limited.
The latest pollution episode has once again drawn attention to the long term environmental challenges facing Delhi and other major Indian cities. Emergency restrictions may provide temporary relief, but stronger controls on vehicle emissions, industrial pollution, construction dust and agricultural burning are needed to address the problem over time.
With Diwali approaching and forecasts warning of continued poor air quality, authorities face the challenge of balancing festival celebrations with public health protection.
The coming days will show whether emergency measures and changing weather conditions can help reduce pollution in a city that is once again struggling with dangerously polluted air.