Abstract
Iron‐cadmium interactions are important in cadmium toxicity. Dietary iron supplements may decrease cadmium retention after oral cadmium exposure but the underlying mechanism is not known. Using a CdS/AgS ion selective electrode to measure [Cd2+] in physiological saline solution at pH 7.4, we show that Fe2+ promotes Cd2+ binding to citrate thereby decreasing the availability of free Cd2+. This suggests the formation of high molecular weight Cd2+‐Fe2+‐citrate complexes. We confirm this suggestion by showing that 109Cd2+ is retained by 1 kDa cut off filters when present with total 50 μM Fe2+ plus 1 mM citrate but not when present with citrate alone. The formation of high molecular weight complexes may prevent Cd2+ absorption. As citrate is part of the diet, we suggest that these iron‐cadmium interactions may contribute to the protective effect of iron against cadmium toxicity.
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Martinez, R., Brassard, P., Mwanjewe, J. et al. Iron promotes cadmium binding to citrate. Mol Cell Biochem 225, 93–96 (2001). https://doi.org/10.1023/A:1012257802703
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DOI: https://doi.org/10.1023/A:1012257802703