Measurements of Inhalable Particles < 10 μm (PM10) and Total Suspended Particulates (TSP) Concentrations along the North–South Corridor, in Kolkata, India

Abstract

The 24-hour concentrations of total suspended particulate matter (TSP) and respirable suspended particulates (PM10) were monitored during March 2003 to February 2004 from a network of 15 sampling stations along a populated urban corridor of Kolkata City in India. The air samplers were placed at a distance 20–200 m from roadways and their height from ground level was within 3 to 5 m. It was also insured that from any obstacle to the airflow was at least 30 cm away. Over the study area, the monthly average concentrations of TSP and PM10 were found to be 200.3 ± 93.1 μg/m3 and 95.8 ± 67.5 μg/m3, respectively, while the 24-hour average concentrations were in the range of 17–456 μg/m3 and 15–291 μg/m3, respectively. The higher average values at particular stations reflected the closeness of those to heavy road traffic. With regards to the temporal variations, higher concentrations were observed during winter and lower concentrations during monsoon. Statistical analysis of the sampling data was conducted to obtain general characteristics of the particulate pollution and to investigate the effects of traffic volume and meteorological factors on the pollution level. TSP and PM10 concentrations were found to be highly correlated with each other at all the sampling stations. There were clear associations between TSP and PM10 data set at all the measured 15 stations and on average, PM10 was 52% of the total TSP concentration.