Adsorbents and methods for removing cations of heavy metals from a medium are provided. The adsorbents comprise a porous media in which at least one oxygen-containing compound of iron, copper, aluminum, zirconium, titanium and combinations thereof is incorporated. The oxygen-containing compound may be incorporated into the porous media by impregnation or dispersion of a suitable precursor of such a compound. The precursor may be further treated to yield the oxygen-containing compound. Such adsorbents are particularly useful for removing lead and/or other metal cations from the environment and may be used in treating drinking water sources.