SEATTLE (AP) - The Center for Biological Diversity filed a federal lawsuit against the Environmental Protection Agency on Wednesday over the threat it says ocean acidification poses to oysters and other sea life off the coasts of Oregon and Washington.
It's the second time in four years the environmental nonprofit has sued the EPA over ocean acidification. The previous lawsuit filed in 2009 was settled out of court in 2010 after the EPA agreed that ocean acidification should be addressed through the federal Clean Water Act.
A spokeswoman for the Center for Biological Diversity said scientific research since that decision has broadened understanding about the impact of rising acidity in oceans, and the Tucson-based environmental group still doesn't think the EPA is doing enough to protect the ocean ecosystem.
"They haven't taken action. We're really concerned," said Miyoko Sakashita. "Now it's the oysters, but it really affects the entire ecosystem, from the smallest plankton to the biggest whale."
Acidification is caused when oceans absorb human-generated carbon dioxide, mostly from the atmosphere and also from nutrient runoff and other sources.
Studies have shown that corrosive water has a dramatic effect on oysters, clams and corals, and it could potentially affect the broader marine food web.
In early 2012, scientists from Oregon State University reported ocean acidification caused oyster larvae to die in 2005 at Whiskey Creek Shellfish Hatchery in Netarts Bay. Other research has chronicled the impact of ocean acidification on other sea life up and down the food chain.
Fast action by the EPA could turn things around, Sakashita said.
"If we stand by and wait for things to get worse, it'll be too late," she added.
Sakashita commended the state governments for doing more than the federal government on this environmental issue.
The lawsuit asks the judge to declare that the EPA violated its duties under the Clean Water Act and acted in a manner that is arbitrary, capricious or unlawful.
A request to the EPA for comment on the lawsuit wasn't immediately answered Wednesday.
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