New insights into the bioaccumulation of persistent organic pollutants in remote alpine lakes located in Himalayas, Pakistan

Javed Nawab; Xiaoping Wang; Sardar Khan; Yu-Ting Tang; Ziaur Rahman; Abid Ali; Jagdish Dotel; Gang Li

doi:10.1016/j.envpol.2020.114952

New insights into the bioaccumulation of persistent organic pollutants in remote alpine lakes located in Himalayas, Pakistan

Environ Pollut. 2020 Jun 7:114952. doi: 10.1016/j.envpol.2020.114952. Online ahead of print.

Authors

Javed Nawab¹, Xiaoping Wang², Sardar Khan³, Yu-Ting Tang⁴, Ziaur Rahman⁵, Abid Ali⁶, Jagdish Dotel⁷, Gang Li⁸

Affiliations

¹ Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Department of Environmental Sciences Abdul Wali Khan University Mardan, Pakistan.
² Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China; University of Chinese Academy of Sciences, Beijing, 100049, China. Electronic address: wangxp@itpcas.ac.cn.
³ Department of Environmental Sciences University of Peshawar, Pakistan.
⁴ School of Geographical Sciences, Research Group of Natural Resources and Environment, University of Nottingham Ningbo China, Ningbo, 315100, China.
⁵ Department of Microbiology, Abdul Wali Khan University Mardan, Pakistan.
⁶ Department of Zoology, Abdul Wali Khan University Mardan, Pakistan.
⁷ Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China.
⁸ CAS Key Laboratory of Urban Environment and Health, Fujian Key Laboratory of Watershed Ecology Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China; Ningbo Urban Environment Observatory and Monitoring Station, Chinese Academy of Sciences, Ningbo, 315830, China.

PMID: 32933786
DOI: 10.1016/j.envpol.2020.114952

Abstract

The current study assesses the persistent organic pollutants (POPs) in water and their bioaccumulation in Brown Trout (BT) and Rainbow Trout (RT) present in the remote alpine lakes (RALs) of Himalayas, Pakistan. Hence, these environments might receive POPs by long range atmospheric transport (LRAT) with little interferences from local anthropogenic activities. The potential transportation pathways for such accumulation can be atmospheric precipitation, melting ice and glacial runoff. The results indicated that the sum of mean concentrations of organochlorine pesticides (OCPs (DDTs + HCHs)) in water of Glacial-fed lakes, Ice melting-fed lake and Rain-fed lake ranged from 0.21 to 317, 0.14-293, 0.16-235 pg L^-1, respectively, while those of polychlorinated biphenyls (PCBs) are 0.275-16.02, 0-15.88, 0.234-14.46 pg L^-1, respectively. Similarly, the sum of mean concentrations of all investigated PCBs and OCPs in BT ranged from 0.008 to 0.715 ng g^-1 and 0.003-3.835 ng g^-1 based on wet weight (ww), while for RT these concentrations were 0.002-0.557 ng g^-1 and 0.001-1.402 ng g^-1 (ww), respectively in the selected RALs. The PCBs and OCPs levels in both water and fish tissues were observed in order of Glacial-fed lakes > Ice melting-fed lake > Rain-fed lake. The results proposed that melting of ice and glacial water are more significant sources of the contaminants (PCBs and OCPs) in the freshwaters of RALs of Himalayas as compared to rainfall water. The positive correlation between water contamination and the selected fish species confirmed that these can be used as a bio-indicator for future research studies. However, the impact of POPs as they cascade through downstream ecosystems remains largely unexplored. The additional study of contaminant dynamics should be extended to a wide range of mountain environments of Himalayas, where melt-water used for drinking and irrigation purposes by billions of people reside alone the waterways that originated from these remote areas.

Keywords: Bioaccumulation; Cancer risk; Long range atmospheric transport; Persistent organic pollutants; Remote alpine lakes; Trout fish.