Distribution and temporal variation of total volatile organic compounds concentrations associated with health risk in Punjab, India

Abstract

Abstract This study demonstrates the substantial changes in the concentration of VOCs in the urban area (Punjab) due to the lockdown effects. We analyzed the data for BTEX over the three years (January to December 2019 to 2021) with pairwise comparison and trend analysis for pre-, during, and post-pandemic periods. The results indicate a substantial reduction in the mean TVOCs concentration for all the monitoring stations was found to be 8.89 ± 1.80, 5.59 ± 1.71, and 5.57 ± 1.43 µg/m3 for before, during, and post-pandemic, respectively. The level of TVOCs declined by -43% for all monitoring stations during the lockdown period compared to the previous years. However, after the lockdown, an increase in the concentration of TVOC by 16% was observed in unlock; this may be due to the re-opening of commercial places, various industries, and transportation, as they are responsible for emissions of BTEX. This reduction indicates an overall improvement in the VOCs due to restrictions on transportation, construction, and the industrial sectors during the lockdown. Despite the overall decreasing trend of VOCs level, few monitoring stations indicate less variation due to meteorological effects. A Higher T/B ratio was found in Patiala (2.97 µg/m3) before the pandemic, which may indicate vehicle (traffic) emission sources and evaporative emission of solvent. The higher level of TVOCs was associated with mobile emission sources and industrial activities. The LCR values for benzene were found to be higher in children than in males and females, which indicated the possible risk. The LCR values for benzene exceeded the prescribed value by CPCB for children.