Tungsten toxicity, bioaccumulation, and compartmentalization into organisms representing two trophic levels

Environ Sci Technol. 2012 Sep 4;46(17):9646-52. doi: 10.1021/es300606x. Epub 2012 Aug 21.

Abstract

Metallic tungsten has civil and military applications and was considered a green alternative to lead. Recent reports of contamination in drinking water and soil have raised scrutiny and suspended some applications. This investigation employed the cabbage Brassica oleracae and snail Otala lactea as models to determine the toxicological implications of sodium tungstate and an aged tungsten powder-spiked soil containing monomeric and polymeric tungstates. Aged soil bioassays indicated cabbage growth was impaired at 436 mg of W/kg, while snail survival was not impacted up to 3793 mg of W/kg. In a dermal exposure, sodium tungstate was more toxic to the snail, with a lethal median concentration of 859 mg of W/kg. While the snail significantly bioaccumulated tungsten, predominately in the hepatopancreas, cabbage leaves bioaccumulated much higher concentrations. Synchrotron-based mapping indicated the highest levels of W were in the veins of cabbage leaves. Our results suggest snails consuming contaminated cabbage accumulated higher tungsten concentrations relative to the concentrations directly bioaccumulated from soil, indicating the importance of robust trophic transfer investigations. Finally, synchrotron mapping provided evidence of tungsten in the inner layer of the snail shell, suggesting potential use of snail shells as a biomonitoring tool for metal contamination.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brassica / drug effects*
  • Brassica / growth & development
  • Brassica / metabolism
  • Environmental Monitoring*
  • Snails / drug effects*
  • Snails / metabolism
  • Snails / physiology
  • Soil Pollutants / analysis
  • Soil Pollutants / metabolism
  • Soil Pollutants / toxicity*
  • Tungsten / analysis
  • Tungsten / metabolism
  • Tungsten / toxicity*
  • Tungsten Compounds / analysis
  • Tungsten Compounds / metabolism
  • Tungsten Compounds / toxicity*

Substances

  • Soil Pollutants
  • Tungsten Compounds
  • Tungsten