Independent research & data-organization project

California's Forgotten Past

The Arsenic Cattle-Dipping Era

An independent investigation into California's state-mandated arsenical cattle-tick dipping program (1907 to 1912), and the South Orange County communities later built on that former ranch land.

Read the report → Download PDF · 103 pp Video script
Priority areas: Ladera Ranch · Bell Canyon / Coto de Caza 19 sections · 109 graded sources
This is an independent research and data-organization project. It does not provide medical advice and does not establish that any pesticide, property, organization, school, water provider, agency, or other party caused any illness. Publicly reported health events may not have been independently medically verified. Geographic and temporal overlap does not establish exposure or causation. No soil has been tested and no contamination is asserted for any community named here.
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