A batch experiment was conducted to examine the combined effects of three common low-molecularweight\udorganic acids (LMWOAs) on the mobilization of arsenic and lead in different types of multicontaminated\udsoils. The capacity of individual LMWOAs (at a same molar concentration) to mobilize\udsoil-borne As and Pb varied significantly. The combination of the organic acids did not make a marked\ud“additive” effect on the mobilization of the investigated three elements. An “antagonistic” effect on\udelement mobilizationwas clear in the treatments involving oxalic acid for some soils. The acid strength of\uda LMWOA did not play an important role in controlling the mobilization of elements. While the mobilization\udof As and Pb was closely associated with the dissolution of soil-borne Fe, soil properties such as\udoriginal soil pH, organic matter contents and the total amount of the element relative to the total Fe\udmarkedly complicated the mobility of that element. Aging led to continual consumption of proton\udintroduced from addition of LMWOAs and consequently caused dramatic changes in solution-borne Fe,\udwhich in turn resulted in change in As and Pb in the soil solution though different elements behaved\uddifferently.
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