Metallothioneins (MTs) were discovered in 1957 when Margoshes and Vallee searched for
a tissue component responsible for the natural accumulation of cadmium in mammalian
kidney. Metallothioneins are still the only biological compounds known to contain this metal.
However, as documented already in the earliest reports, cadmium is but one of several
optional metallic components, the others being most commonly zinc and copper. 2-4 In fact,
in subsequent studies zinc 5 and/or copper were often found to be the sole constituents …