The non-partisan National Research Council has come out with a report concerning carbon monoxide (CO) pollution:

Once a far-reaching menace, carbon monoxide emissions from cars and pickups are now a stubborn problem mostly in the West, where weather and terrain tend to trap pollution, the National Research Council says. Federal air quality standards and tailpipe emissions controls over the past three decades have reduced concentrations of the gas, the council said in a new report.

This is great news. As a nation we have taken great strides to reduce harmful emissions which contribute to numerous pollution concerns.

THIS REGULATION “has been one of the greatest success stories in air pollution control, reducing the problem, once widespread, to a few difficult areas,” panel members wrote in their report to Congress.
When it persists in the air, the colorless, odorless, poisonous gas enters the bloodstream through the lungs. It comes mainly from incomplete burning of carbon in fuel and in other products such as cigarette smoke.
To illustrate the success, the council, which is part of the National Academy of Sciences, pointed to Denver and Fairbanks, Alaska. Denver has not violated the federal standards for carbon monoxide since 1995, but did so for as many as 200 days a year in the 1960s. Fairbanks has not violated the standard the past two years; it did more than 100 days a year in the 1970s.
By contrast, Anchorage, Alaska and the southern California cities of Lynwood and Calexico have persistent carbon monoxide problems usually due to severe atmospheric conditions in which temperatures rise with altitude, the academy said.

The reduction in Denver is significant as the region has seen a huge increase in people relocating there.

Ted Russell, an engineering professor at the Georgia Institute of Technology who was the study chairman, said more reductions in carbon monoxide pollution can be expected as a result of EPA rules taking effect next year to reduce pollutants that form ozone, a precursor of smog.
“The same controls that affect hydrocarbons also tend to impact carbon monoxide,” he said.

Frank O’Donnell, executive director of the Clean Air Trust, an environmental advocacy group, said the story of carbon monoxide shows the success of tough regulations — and enforcing them.

The Clean Air Trust is no fan of Republicans or Bush. You sure don't see many instances where they are given a shot to slam the administration and don't.
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