As stated in an article on Discovery News Online, recently the USA supreme court has come to a conclusion:

“that greenhouse gases contribute to air pollution that may endanger public health or welfare”

Original link: http://dsc.discovery.com/news/2009/04/17/co2-health-epa.html

EPA Deems CO2 a Health Risk

April 17, 2009 — The U.S. Environmental Protection Agency shifted course and deemed carbon dioxide a health risk on Friday, in a turnabout important to global warming-related regulation.

“After a thorough scientific review ordered in 2007 by the U.S. Supreme Court, the Environmental Protection Agency issued a proposed finding … that greenhouse gases contribute to air pollution that may endanger public health or welfare,” an EPA statement posted on the agency website read.

“This finding confirms that greenhouse gas pollution is a serious problem now and for future generations. Fortunately, it follows President (Barack) Obama’s call for a low carbon economy and strong leadership in Congress on clean energy and climate legislation,” Administrator Lisa Jackson said.

“This pollution problem has a solution — one that will create millions of green jobs and end our country’s dependence on foreign oil.

“As the proposed endangerment finding states, ‘In both magnitude and probability, climate change is an enormous problem. The greenhouse gases that are responsible for it endanger public health and welfare within the meaning of the Clean Air Act,'” she added.

Five out of the nine Supreme Court justices ruled in April 2007 that carbon dioxide was a pollutant under the Clean Air Act.

They ordered the EPA to decide if the greenhouse gas endangered public health and welfare and said that if a so-called endangerment finding was made, the agency must draft rules to reduce vehicle emissions of carbon dioxide.

In December 2007, the EPA sent a draft finding to the Bush White House, presenting evidence that CO2 did endanger public welfare.

But the administration of president George W. Bush failed to acknowledge the report and spent the remainder of its tenure resisting the Supreme Court decision.

Many environmental groups have been appalled that the Bush administration refused for eight years to take action over the crisis and in their view manipulated or ignored science to pursue inaction, at any cost.

John Walke, a senior attorney at the National Resources Defense Council, said last month that such an EPA shift would “make findings that greenhouse gas emissions not only endanger public welfare — ecosystems, the environment and the planet at large — but also make the important link between global warming emissions and how they will affect smog pollution, malaria and other public health problems.”