Binding, distribution, and plant uptake of mercury in a soil from Oak Ridge, Tennessee, USA.
A large amount of mercury has been discharged on the U.S. Department of Energy's Oak Ridge Site (Tennessee) as a part of the U.S. nuclear weapon program during the 1950s through the early 1960s. Increases in mercury concentration in fish and in lower East Fork Poplar Creek of Oak Ridge have been recently reported. This is an experimental study mimicking the initial stage of transformation and redistribution of mercury in soils, which are comparable to those of the Oak Ridge site. The objectives of this study were to investigate potential transformation, distribution, and plant uptake of mercury compounds in soils. Results show that the H(2)O(2)-oxidizable mercury fraction (organically bound mercury) was the major solid-phase fraction in soils freshly contaminated with soluble mercury compounds, while cinnabar fraction was the major solid phase fraction in soils contaminated with HgS. Langmuir relationships were found between mercury concentrations in plant shoots and in soil solid-phase components. Mercury in HgS-contaminated soils was to some extent phytoavailable to plants. Mercury transformation occurred from more labile fractions into more stable fractions, resulting in strong binding of mercury and decreasing its phytoavailability in soils. In addition, high mercury losses from soils contaminated with soluble mercury compounds were observed during a growing season through volatilization, accounting for 20-62% of the total initial mercury in soils.
Han
Fengxiang X
FX
Diagnostic Instrumentation and Analysis Laboratory (DIAL), Mississippi State University, 205 Research Blvd., Starkville, MS 39759, USA. han@dial.msstate.edu
Su
Yi
Y
Monts
David L
DL
Waggoner
Charles A
CA
Plodinec
M John
MJ
D006861:Hydrogen Peroxide / Q000737:chemistry; D008628:Mercury / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D017669:Mercury Compounds / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D018517:Plant Roots / Q000737:chemistry; D018520:Plant Shoots / Q000737:chemistry; D032495:Pteris / Q000378:metabolism*; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism*; D013714:Tennessee; D014835:Volatilization
D017669:Mercury Compounds; D012989:Soil Pollutants; D006861:Hydrogen Peroxide; D008628:Mercury