The role of environmental mercury, lead and pesticide exposure in development of amyotrophic lateral sclerosis

Abstract

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 ~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.

Progress toward the clinical application of patient-specific pluripotent stem cells

“…The etiology of such forms of these diseases is unclear, but it is thought that they arise from complex interactions between genetic and environmental factors (82). Environmental factors, including toxic pesticides and metals, general lifestyle, and dietary habits have been associated with increased risk of disease (83,84) and are likely to be mirrored in epigenetic alterations. During the reprogramming process, the epigenetic landscape of cells is redrawn, as a terminally differentiated cell is transformed into a pluripotent one.…”

Shannon Entropy in a European Seabass (Dicentrarchus labrax) System during the Initial Recovery Period after a Short-Term Exposure to Methylmercury

“…MeHg is a neurotoxic substance and chronic exposure to it induces, among others, symptoms similar to those observed in amyotrophic lateral sclerosis, such as the early onset of hind limb weakness in humans [12,13]. The active swimming in salmon is affected by MeHg [13].…”

An Unusual Case of Neurogenic Sexual Dysfunction Due to Lead Exposure

“…Lead is present in water [17], paint [18], brass plumbing fixtures [19], ayurvedic medicine [20,21], aphrodisiacs [22], alternative medications [23], etc. Lead is toxic to numerous organ systems, which include bone marrow, muscles, kidneys, endocrine glands, joints, and nervous system [24][25][26][27]. Low-level blood lead levels may be causative factors in cognitive dysfunction, neurobehavioral disorders, neurological damage, hypertension, cardiac dysfunction and renal impairment [28].…”