organs of their toxicity, especially at low doses present in the environment,
are rather sparse and inconclusive. Research on
mechanisms of joint toxicity of Pb and Cd are in progress and the
available studies provide evidence of synergistic or antagonistic
interactions depending on duration, dose of exposure and type of
investigated organ. Hence, studies on toxicity of mixtures, not only
of these two metals but also on mixtures of other metals and mixtures
of metals with other toxic agents, continue to be one of the
greatest challenges of contemporary toxicology