Manifestations of copper excess.

Although copper is an essential micronutrient normally subject to effective homeostatic control, excess dietary intakes can in some circumstances be toxic. Susceptibility to copper toxicosis depends, however, on many factors, including species, genetics, age, and diet. This appears to reflect not only variations in the efficiency of the absorption and excretion of copper but also differences in the intake of other hepatotoxic or protective factors, differences in the cellular distribution of copper, and differences in the expression of specific copper transport and storage proteins. Many of the toxic effects of copper, such as increased lipid peroxidation in cell membranes and DNA damage, are related to its role in the generation of oxygen free radicals.