Phosphate application to firing range soils for Pb immobilization: The unclear role of phosphate

In-situ immobilization of lead using different source of phosphate amendments for the organic production of misai kucing (Orthosiphon stamineus)

“…The total solubility of P are in order of: ERP<BM<TSP. High solubility of Pb and P is required for a successful Pb immobilization for formation of pyromorphite other than low soil pH and high Pb/P ratio (Chrysochoou et al 2007). Thus, TSP and BM are probably better materials to immobilize Pb based on assessment made on their solubility.…”

Phosphate-Mediated Remediation of Metals and Radionuclides

“…[87][88][89]. The use of orthophosphate solutions within surface soils and deep subsurface environments requires strategies that prevent (1) rapid precipitation of contaminants and other sediment components (e.g., Al, Ca, Fe, Mg, and Mn) that affects hydraulic conductivity, (2) leaching of metals (e.g., As, Se, and W), and (3) ecosystem eutrophication caused by excess P runoff [82,[89][90][91]. Compounds such as phytic acid (i.e., the acid form of inositol-6-phosphate) and polyphosphate have been examined for their ability to (1) act as sites for ion exchange, (2) facilitate the slow delivery of orthophosphate, and (3) act as chelating agents that minimize the bioavailability of cations within contaminated environments [92][93][94][95].…”

Trace Element Immobilization in Soil Using Amendments

“…The newly formed minerals have been demonstrated to significantly reduce Pb bioaccessibility and bioavailability [122,[135][136][137]. A review of Pb immobilization by phosphate amendments is given by Chrysochoou and co-authors [138].…”

“…For successful Pb immobilization through pyromorphite formation, low soil pH, high solubility of Pb and P, and high P/Pb ratios are required, which all are high environmental risk factors. Therefore, Pb immobilization using phosphates in field applications should be considered very carefully and might have more disadvantages than benefits [138].…”