S. Sauve et al., Solid-solution partitioning of metals in contaminated soils: Dependence onpH, total metal burden, and organic matter, ENV SCI TEC, 34(7), 2000, pp. 1125-1131
Citations number
82
Categorie Soggetti
Environment/Ecology,"Environmental Engineering & Energy
Environmental risk assessment of metals depends to a great extent on modeli
ng the fate and the mobility of metals based on soil-liquid partitioning co
efficients. A large variability is observed among the reported values that
could be used to predict metal mobility and bioavailability. To evaluate th
is, soil-liquid partitioning coefficients (K-d) for many elements but espec
ially for the meta Is cadmium, copper, lead, nickel, and zinc were compiled
from over 70 studies of various origins collected from the literature. The
relationships between the reported values are explored relative to variati
ons in soil solution pH, soil organic matter (SOM), and concentrations of t
otal soil metal. The results of multiple linear regressions show that K-d v
alues are best predicted using empirical linear regressions with pH (with R
-2 values of 0.29-0.58) or with pH and either the log of SOM or the log of
total metal and with resulting R-2 values of 0.42-0.76. A semi-mechanistic
model based on the competitive adsorption of metal and H+ [dependent on sol
ution pH, total metal content, and log(SOM)] was a better tool to predict d
issolved metal concentrations (with R-2 values of 0.61-0.88), with the exce
ption of Pb (at 0.35).