When residents of San Diego de la Unión turn on the tap, they risk exposure to arsenic and fluoride levels that violate health standards, prompting their mayor to demand urgent regional action.
Michelle Betz reports for Mexico News Daily.
In short:
- Groundwater testing in San Diego de la Unión found 20 of 23 rural wells unsafe, with arsenic or fluoride levels above legal limits, affecting 59 out of 71 communities.
- Mayor Juan Carlos Castillo Cantero called the situation a “ticking time bomb” and urged collective action from neighboring municipalities and higher levels of government.
- In response, over 490 rainwater harvesting systems have been installed since 2021, with grassroots and nonprofit partnerships leading community-based solutions.
Key quote:
“This isn’t just about water. It’s about systemic health deterioration — kidney failure, dental and crippling skeletal fluorosis, cognitive issues in children. And it’s all invisible until it’s too late.”
— Dylan Terrell, executive director of the NGO Caminos de Agua
Why this matters:
In many parts of Mexico and beyond, rural communities rely on groundwater that may appear clean but hides dangerous contaminants. Arsenic and fluoride, both naturally occurring and made worse by industrial and agricultural practices, can cause irreversible damage with long-term exposure — including cancer, organ failure, and developmental issues in children. These contaminants are odorless and tasteless, making them especially dangerous in places with little water quality monitoring. San Diego de la Unión’s case is a window into a broader crisis: communities unknowingly drinking poisoned water while infrastructure and funding gaps leave them exposed. As populations grow and aquifers are drained, the need for collective water stewardship — and public awareness — becomes urgent. Similar risks exist across Latin America and the southwestern United States.
Related: Mexico’s new president faces major water crisis challenge
