Texas A&M researchers have started a $1.5 million dollar study to understand arsenic and other heavy metals in Valley drinking water. The Valley made the top of the list after complaints and state-documented hotspots convinced the study organizers to focus on this area.

At the center of those complaints are homes served by Military Highway Water Supply Corporation. Residents have complained about tainted, colored water for years. Records also show arsenic levels spiked those taps four times in the last two years.

"Looks like coffee," said Herardo Jimenez, a customer who lives in the area of Santa Maria. He recently replaced his washing machine because the previous one was stained red with mineral deposits.

Multiple residents complained their clothes were regularly stained from the water. Others say they've developed health issues.

"Both of them had rashes over the body," said Araceli Palomino. "My daughter specifically was having a lot of stomach pain."

Arsenic is linked to cancer by multiple health organizations. Long-term exposure increases the severity of symptoms.

"We are talking about risk for cardiovascular disease, cancer risk, kidney disease, neurological outcomes, skin diseases," said Dr. Ana Navas-Nacien, a professor of Environmental Health Sciences at Columbia University.

"Communities should be bringing that arsenic as close to zero as possible," she said.

In January, the university announced the start of a partnership with Methodist Healthcare Ministries and, with $1.5 million in funding, they started looking into those hotspots that the TCEQ identified.

"I believe this project will show a clear picture of arsenic exposure among residents in the Rio Grande Valley," said Dr. Taehyun Roh, a professor of Epidemiology and Bio Statistics at Texas A&M.

This June, they started sampling water at 30 homes and biomonitoring residents, checking their hair and nail samples.

The Military Highway Water Supply Corporation refused to speak on the issue and referred to their legal counsel attorneys at O'Hanlon Dermath and Castillo, who also did not reply to several requests for comment and information.

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