Zinc solubility in contaminated roadside soils from Caracas, Venezuela

Abstract

ZINC SOLUBILITY IN CONTAMINATED ROADSIDE SOILS FROM CARACAS, VENEZUELA KEY WORDS; Heavy metal soil pollution, zinc solubility, zinc chemistry, contaminated roadside soils. ABSTRACT Zinc solubility in three Zn contaminated roadside soils from Caracas, Venezuela, was studied. Solubility diagrams were constructed for the three soils and compared to well known sparingly soluble Zn solid phases. At pH values below 8.0, ion exchange and other ion snrption mechanisms in soil materials, seem to control Zn solubility in the soils studied. For pH v-alues above 8.0 the possible precipitation of the compound Zn(OH) 2 was found. Therefore Zn activity in soil solution seems to be controlled by Zn(0H) 2 solubility at pH above 8.0 in the soils studied. Differences in Zn solubilities for the three soils were attributed mainly to the differences in their Zn contents. Some practical implications of the results are discussed. 219 Copyright© 1981 by Marcel Dekker, Inc.