Conclusions

Dissolved organic matter isolated from the Everglades, FL interact very strongly with cinnabar releasing significant quantities of Hg into solution. The humic fractions of DOM (humic acid, fulvic acid, and hydrophobic acid) released more Hg than the non-humic fractions.

Additional work is required to explain the nature of interaction between cinnabar and organic matter. Future research work could involve experiments carried out under strict anoxic conditions, measuring concentrations of various sulfur species in solution, and identifying sulfur species on mineral surface by various spectroscopic methods.

Irrespective of which mechanism is responsible for the dissolution of cinnabar, the ubiquitous presence of humic substances in natural waters makes the organic matter-enhanced solubilization of mercury a potentially important source of mercury in contaminated and pristine soils, sediments, pore waters, and surface waters.

---

USGS home page || USGS WRD National Research Program Web Page
The URL of this page is: http://wwwbrr.cr.usgs.gov/projects/SW_corrosion/mercury-poster/index.html
Comments and feedback: cgunther@usgs.gov
Last modified: Monday, 15-June-98 15:50:14 MST