Arizona Officials: Fish From Gila River Are Safe To Eat

Published: Wednesday, September 30, 2015 - 7:35pm
Updated: Thursday, October 1, 2015 - 10:30am
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(Image courtesy of the Arizona Department of Environmental Quality)
The map shows areas of the Gila River where pesticide levels were high, prompting officials to advise people not eat them. The advisory was lifted Wednesday after 24 years.
(Chart courtesy of the Arizona Department of Environmental Quality)
This chart lists all the places impacted by the lifting the consumption advisory.

For the first time in 24 years, the Arizona Department of Environmental Quality has said fish plucked from parts of the Gila River are safe to eat.  

Banned pesticides like DDT, chlordane and toxaphene led to a 1990s warning against eating fish from the river. Tests back then showed that fish contained pesticide levels about 160 times above what’s considered safe for human consumption.

But 2011 and 2012 test results revealed that pesticide levels had dropped 16 times below the threshold. That was somewhat surprising because pesticides can persist in the environment, said Jason Jones, supervisor of ADEQ's monitoring and assessment unit.  

“Since they were banned several decades ago, they probably just worked through the ecosystems,” Jones said. “After 20, 30 years a lot of those pesticides that weren’t being used are either washed out of the system or just degrade.”

The drop in pesticide levels shows a balancing of agricultural and wildlife interests, said Dr. Kevin Fitzsimmons, a professor of environmental science at the University of Arizona.

“It’s a really good example of how, with good regulations, the farmers have been able to protect their field crops and at the same time improve the environment,” Fitzsimmons said.

Impacted portions of the river and its tributaries lie in Phoenix, the West Valley and Gila Bend. They include parts of the Salt and Hassayampa rivers.

The Gila River was the only body of water in Arizona with a consumption advisory based on pesticide levels, and it the first time one has been lifted. Other consumption advisories exist because of mercury.

Science