Atmospheric polychlorinated biphenyls in a non-metropolitan city in northern India: Levels, seasonality and sources. (January 2021)

• Record Type: Journal Article
• Authors: Prithiviraj, Balasubramanian; Taneja, Ajay; Chakraborty, Paromita
• Is Part Of: Chemosphere. Volume 263(2021)
• Publication Date: 2021-01
• Subjects: Non-metropolitan -- India -- Atmosphere -- PUF-PAS -- PCBs -- Back trajectory; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2020.127700
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Recent studies from India reported polychlorinated biphenyls (PCBs) associated with incomplete combustion processes. In this study we have monitored atmospheric PCBs in Agra, a non-metropolitan city of northern India. During first month of summer and winter of 2017, polyurethane foam based passive air sampler (PUF-PAS) was deployed at each of 14 locations across urban, suburban and rural transects and one background site. Range of Σ25 PCBs varied between 25 and 1433 pg/m 3 (Avg ± Stdev: 460 ± 461) in summer and 26–205 pg/m 3 (Avg ± Stdev: 106 ± 59) in winter. Mean Σ25 PCBs concentration, showed an urban > suburban > rural trend in summer while, in winter a rural > urban > suburban trend was observed. PCB-52 was the dominant congener and after excluding this congener no significant difference was observed between summer and winter PCB concentrations. Using a combination of K-means cluster and principal component analysis (PCA) four major source types were identified. Open burning source accorded 80% of atmospheric PCBs, majorly indicator PCBs while the remaining 20% was contributed by atmospheric transport, petrogenic combustion and biomass burning. From the ten days back trajectory of the air mass it can be suggested that atmospheric transport from the hotspots resulted in a minor percentage of dioxin like PCBs in Agra. Maximum TEQs was accorded by PCB-77 (30%) and it is consistent with previous observations from Agra. Levels observed in the current study are well within the public health guideline based on inhalation unit risk (10 ng/m 3 ) and United States Environmental Protection Agency's regional screening level high risk tier (4.9 ng/m 3 ) for ambient air. Graphical abstract: Image 1 Highlights: During summer distinct urban > suburban > rural trend was observed in Agra. Elevated PCBs in the rural transect during winter is presumably due to biomass burning. PCB-52 is the dominant congener and related to open burning of dumped municipal waste. Minor fraction of dioxin like PCBs might have resulted from short range atmospheric transport.