Sedimentary black carbon and organochlorines in Lesser Himalayan Region of Pakistan: Relationship along the altitude

Usman Ali; Andrew James Sweetman; Rahat Riaz; Jun Li; Gan Zhang; Kevin C Jones; Riffat Naseem Malik

doi:10.1016/j.scitotenv.2017.10.071

Sedimentary black carbon and organochlorines in Lesser Himalayan Region of Pakistan: Relationship along the altitude

Sci Total Environ. 2018 Apr 15:621:1568-1580. doi: 10.1016/j.scitotenv.2017.10.071. Epub 2017 Nov 8.

Authors

Usman Ali¹, Andrew James Sweetman², Rahat Riaz¹, Jun Li³, Gan Zhang³, Kevin C Jones², Riffat Naseem Malik⁴

Affiliations

¹ Department of Environmental Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan.
² Centre for Chemicals Management, Lancaster Environment Centre, Lancaster University, Bailrigg, Lancaster LA1 4YQ, UK.
³ State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
⁴ Department of Environmental Sciences, Quaid-i-Azam University, Islamabad 45320, Pakistan. Electronic address: r_n_malik@qau.edu.pk.

PMID: 29126639
DOI: 10.1016/j.scitotenv.2017.10.071

Abstract

Black carbon (BC) and total organic carbon (TOC) along with their relationship with organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were assessed in Lesser Himalayan Region (LHR) in different altitudinal zones based on anthropogenic influence/source proximity under the scope of this study. Results revealed the concentrations of BC, TOC, OCPs and PCBs varied between 0.3 and 43.5mgg^-1, 1.7-65.4mgg^-1, 0.59-3.64ngg^-1 and 0.01-1.31ngg^-1, respectively. Spatial distribution trends have shown higher levels of OCPs and PCBs contamination near populated and urban areas along the altitude. It is implicated that upslope, short and long-range transport and local emission sources contribute to the contamination of different altitudinal zones of LHR. The relationship of BC and TOC with OCPs and PCBs was evaluated using principal component analysis (PCA) and Pearson correlation analysis that indicated higher sorptive influence of BC over TOC in distribution status of organochlorines in LHR. Further research is required to find relationship of BC and TOC in surface riverine sediments, particularly in aquatic systems along the altitude in mountain regions of the world.

Keywords: Altitude; Black carbon; Lesser Himalayan Region; Local source emissions; OCPs; PCBs.