So it's not safe to breathe air containing trace amounts of carbon dioxide?

ARB chairman tells U.S. Senate committee Clean Air Act is powerful tool to fight global warming

Washington, D.C. Sep. 23, 2008 - Mary Nichols, chairman of the California Air Resources Board, today told a Senate Committee in Washington D.C. that Congressional action is urgently needed to set a firm and ambitious cap on greenhouse gas emissions.

The ARB chairman addressed the Senate Committee on the Environment and Public Works, chaired by Senator Boxer.

"California, and other states are already seeing the effects of global warming," said Nichols. "We need action now. Addressing climate change with tough federal legislation must be the first item in the new President's inbox."

In April, 2007, the U.S. Supreme Court ruled that carbon dioxide is a pollutant and ordered the EPA to examine the impacts of global warming and how it could regulate greenhouse gases. Instead, the EPA only described the harm, but declined to make a definitive statement.

"We cannot wait another minute to begin to reverse the neglect of the past eight years and start to reduce greenhouse gas emissions," she said. "The Clean Air Act is a powerful tool that is ready to be put to use starting on day one of the next administration."
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While in Washington D.C., Nichols also met with representatives of the American Lung Association to discuss the growing body of evidence about the impacts of global warming on public health, particularly respiratory and other diseases.