Effects of Nationwide Lockdown due to COVID-19 on Ambient Air Quality in the State of West Bengal, India

Abstract

The present study assessed the nationwide lockdown impacts on the air pollution situation across West Bengal, India. Air pollution data was collected from the online monitoring stations of the Central Pollution Control Board across West Bengal. The gradual declining pattern of overall pollution status was observed during the lockdown phase from the pre-lockdown phase. The early unlocking stage found slow and gradual increasing air pollution levels. Siliguri’s pre-lockdown ‘poor’ Air Quality Index (AQI) improved in the lockdown phase to ‘satisfactory’ level. ‘Moderate’ level AQI in Asansol of the pre-lockdown stage improved to ‘satisfactory’ level during the lockdown phase. Pre-lockdown AQI of both Kolkata and Howrah changed from ‘moderate’ to ‘good’ level during the lockdown phase. Unlike other pollutants, the ozone level increased in Kolkata, Howrah, and Siliguri in the lockdown phase. The early monsoonal washout possibly caused the changes in the pattern of pollution status of specified periods in the 2019 and 2020. Thus, in the study period of lockdown in 2020, the decrease in pollution level may not only caused by the stoppage of vehicles or industry but also have a possible natural influence.

A Comparative Study of Heavy Metal Pollution in Ambient Air and the Health Risks Assessment in Industrial, Urban and Semi-Urban Areas of West Bengal, India: An Evaluation of Carcinogenic, Non-Carcinogenic, and Additional Lifetime Cancer Cases

“…Durgapur is a heavily industrialized area, making it susceptible to pollution from various sources, including heavy industry, power plants, manufacturing emissions, movements of heavy vehicles, and burning of fossil fuels for multiple operations, causing a significant amount of particulate matter to be discharged into the atmosphere [38]. On the other hand, Kolkata, a densely populated city, is faced with severe traffic congestion (vehicle emissions), ongoing construction projects, and industrial activities, which result in significant pollution sources in this area [8,39,40]. In the case of Bolpur, various factors, including agriculture, soil dust, domestic cooking, and rice mill emissions, may significantly contribute to air pollution [38].…”