The Role of Environmental Mercury, Lead and Pesticide Exposure in Development of Amyotrophic Lateral Sclerosis.
Center for Integrative Toxicology and Neuroscience Program and Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI 48824, USA.
Exposure to an environmental toxicant as a risk factor in the development of amyotrophic lateral sclerosis (ALS) was first hinted (demonstrated) in the Chamorro indigenous people of Guam. During the 1950s and 1960s these indigenous people presented an extremely high incidence of ALS which was presumed to be associated with the consumption of flying fox and cycad seeds. No other strong association between ALS and environmental toxicants has since been reported, although circumstantial epidemiological evidence has implicated exposure to heavy metals such as lead and mercury, industrial solvents and exposure to pesticides especially organophosphates and certain occupations such as playing soccer. Given that only approximately 10% of all ALS diagnosis has a genetic basis, a gene-environmental interaction provides a plausible explanation for the other 90% of cases. This mini-review provides an overview of our current knowledge of environmental etiologies of ALS with emphasis on the effects of mercury, lead and pesticides as potential risk factors in developing ALS. Epidemiologic and experimental evidence from animal models investigating the possible association between exposure to environmental toxicant and ALS disease has proven inconclusive. Nonetheless, there are indications that there may be causal links, and a need for more research.
PMID: 19632272 [PubMed - as supplied by publisher]