POP and PAH contamination in the southern slopes of Mt. Everest (Himalaya, Nepal): Long-range atmospheric transport, glacier shrinkage, or local impact of tourism?

Sci Total Environ. 2016 Feb 15:544:382-90. doi: 10.1016/j.scitotenv.2015.11.118. Epub 2015 Dec 3.

Abstract

Due to their physico-chemical properties, POPs and PAHs are subjected to long-range atmospheric transport (LRAT) and may be deposited in remote areas. In this study, the contamination with DDx, PCBs, PBDEs, and PAHs was investigated in sediments and soils collected on the southern slopes of Mt. Everest (Himalaya, Nepal) in two different sampling campaigns (2008 and 2012). The results showed a limited contamination with POPs and PAHs in both soil and sediment samples. Therefore, the southern slopes of Mt. Everest can be considered a remote area in almost pristine condition. The LRAT mechanism confirmed its primary role in the transfer of contaminants to remote regions, while the gradual melting of glaciers, due to global warming, and the subsequent release of contaminants was suggested to be a secondary source of pollution of the lake sediments. In addition, the increase of tourism in this area during the last decades might have influenced the present concentrations of PAHs in the sediments and soils.

Keywords: Global warming; Himalaya; Long-range atmospheric transport; Persistent organic pollutants; Polycyclic aromatic hydrocarbons.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Environmental Monitoring*
  • Environmental Pollutants / analysis*
  • Geologic Sediments
  • Halogenated Diphenyl Ethers / analysis
  • Ice Cover
  • Nepal
  • Polychlorinated Biphenyls / analysis
  • Polycyclic Aromatic Hydrocarbons / analysis

Substances

  • Environmental Pollutants
  • Halogenated Diphenyl Ethers
  • Polycyclic Aromatic Hydrocarbons
  • Polychlorinated Biphenyls