Exposure to an environmental toxicant as a risk factor in the development of amyotrophic
lateral sclerosis (ALS) was first hinted at (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 …