Contaminants in California Drinking Water Linked to Autism and Health Risks.
Water in California's Central Valley contains high levels of manganese, which can cause cognitive disabilities and motor control issues in children, and Parkinson's-like symptoms in adults. The highest concentrations of manganese are found in private, untreated well water systems, but it is also present in public water systems at higher concentrations than what studies have shown can have adverse health effects. Nearly half of all domestic well water users in the Central Valley live in disadvantaged communities, and nearly 89% of them have a high likelihood of accessing water that is highly contaminated with manganese.