PHOENIX - Friday was another high-pollution day in Maricopa County, the Arizona Department of Environmental Quality warned.

Ozone levels were at dangerously high levels, prompting the state and county to warn people to stay indoors, and either telecommute or carpool to try to reduce pollution.

But ADEQ admits that while the number of high pollution advisory days may have gone up, it doesn't necessarily mean the air quality in the Valley is getting worse.

"The more stringent standard is why we're seeing more health watches and high pollution advisories, said ADEQ Air Quality Director Timothy Franquist. 

In 2005, the Environmental Protection Agency lowered the level that ozone must reach to trigger an advisory. 

Air quality officials told 12 News that they estimate more than half the pollution in Arizona air comes from Asia, so there's little they can do to combat the pollution in the air. Combine that with more cars on the road, and more sunlight in the West that interacts with compounds to form ozone, and Arizona gets more pollution advisories.

But the EPA's own numbers show the number of high ozone days has declined since 2000.

Arizona even sued the EPA, along with four other states, over the new ozone standards, saying they're unrealistic and punish the state for pollution that's out of it's control. That lawsuit, officials said, is still pending. 

So, we can verify that the alerts are legitimate, even as we can verify that the Valley's air quality is not getting worse.