Organic persistent toxic substances in soils, waters and sediments along an altitudinal gradient at Mt. Sagarmatha, Himalayas, Nepal

Environ Pollut. 2011 Oct;159(10):2552-64. doi: 10.1016/j.envpol.2011.06.015. Epub 2011 Jul 14.

Abstract

Persistent Organic Pollutants (POPs) and Polycyclic Aromatic Hydrocarbons (PAHs) are important classes of compounds of serious environmental concern. These compounds were measured in waters, sediments and soils from several high altitude sites in the Sagarmatha National Park (Nepal) and included in the Himalayan ridge. In water samples, low-level substituted PCBs and PBDEs, along with more volatile PAHs, were the most common contaminants. In sediment and soil samples, the PCB profile was mainly composed of medium-level chlorinated congeners and significantly correlated with altitude. The PAH profile for water and soil samples showed the main contribution of pyrogenic PAHs due to emissions of solid combustion, whereas the profile for sediments indicated the main contribution of pyrogenic PAHs from gasoline emissions. The PAH levels measured in Himalayan samples must be considered as low to medium contaminated, whereas the regarded Himalayan stations can be considered undisturbed remote areas concerning PCB, PBDE and OC compounds.

MeSH terms

  • Altitude
  • Environmental Monitoring
  • Environmental Pollutants / analysis*
  • Environmental Pollutants / toxicity
  • Environmental Pollution / statistics & numerical data
  • Fresh Water / chemistry*
  • Geologic Sediments / chemistry*
  • Halogenated Diphenyl Ethers / analysis
  • Hazardous Substances / analysis*
  • Hazardous Substances / toxicity
  • Nepal
  • Organic Chemicals / analysis*
  • Organic Chemicals / toxicity
  • Polychlorinated Biphenyls / analysis
  • Polycyclic Aromatic Hydrocarbons / analysis
  • Soil / chemistry*

Substances

  • Environmental Pollutants
  • Halogenated Diphenyl Ethers
  • Hazardous Substances
  • Organic Chemicals
  • Polycyclic Aromatic Hydrocarbons
  • Soil
  • Polychlorinated Biphenyls