Metal toxicity
Toxic metals sometimes imitate the action of an essential element, interfering with the metabolic processes resulting in illness.
Ligands can range from water in metal aquo complexes to methyl groups as in tetraethyl lead.
Toxic metal complexes can be detoxified by conversion to insoluble derivatives or (ii) by encasing in rigid molecular environments using chelating agents.
[4] An aspirational method of decontamination of heavy metals is phytoremediation or bioremediation, but these approaches have solved few real world problems.
This is particularly notable with radioactive heavy metals such as radium, which imitates calcium to the point of being incorporated into human bone, although similar health implications are found in lead or mercury poisoning.
[7][8] One lead-containing pigments is lead chromate (the yellow-orange of U.S. school buses), but this material is so stable and so insoluble that little evidence exists for its toxicity.
In the case of the lanthanides, the definition of an essential nutrient as being indispensable and irreplaceable is not completely applicable due to their extreme similarity.
Complexation prevents the metal ions from reacting with molecules in the body, and enable them to be dissolved in blood and eliminated in urine.
[35] It is difficult to differentiate the effects of low level metal poisoning from the environment with other kinds of environmental harms, including nonmetal pollution.
