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Published on: December 17, 2018
Methylated metal(loid) species in humans
Alfred V Hirner1, Albert W Rettenmeier
1Instituto de Ciencia de Materiales de Aragón, CSIC-Universidad de Zaragoza, Departamento de Física de la Materia Condensada, 50009, Zaragoza, Spain. evange@unizar.es
Metal Ions in Life Sciences
|September 30, 2010
Summary
Methylation of toxic metal(loid)s like arsenic and selenium in the body increases their mobility, potentially impacting human health. This review compiles data on methylated metal(loid)s and their health effects.
Area of Science:
- Environmental Science
- Toxicology
- Human Health
Background:
- Certain metal(loid)s (arsenic, bismuth, selenium, tellurium) are known to be enzymatically methylated in the human body.
- Biomethylation of other metal(loid)s (antimony, cadmium, germanium, indium, lead, mercury, thallium, tin) occurs in the environment but is not yet demonstrated in humans.
- Methylated metal(loid) species exhibit enhanced mobility and can more easily cross biological membranes, including the blood-brain and placental barriers.
Purpose of the Study:
- To compile and discuss existing literature on the biomethylation of metal(loid)s.
- To evaluate the assumed and proven health effects associated with methylated metal(loid) species in humans.
- To highlight the implications of metal(loid) methylation on human health and toxicokinetics.
Main Methods:
- Literature review and synthesis of relevant scientific data.
- Compilation of studies demonstrating or suggesting metal(loid) methylation in biological systems.
- Analysis of toxicological data concerning alkylated metal(loid) species.
Main Results:
- Confirmed enzymatic methylation in vivo for arsenic, bismuth, and selenium.
- Identified environmental biomethylation for antimony, cadmium, germanium, indium, lead, mercury, thallium, and tin.
- Documented increased mobility and membrane permeability of methylated metal(loid)s.
Conclusions:
- Methylation significantly alters metal(loid) behavior and distribution within the human body.
- The potential for methylated metal(loid)s to affect human health, particularly via crossing critical biological barriers, warrants further investigation.
- Understanding metal(loid) methylation is crucial for assessing toxicological risks and developing effective health strategies.
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