“Gov. Romney does not think greenhouse gases are pollutants within the meaning of the Clean Air Act, and he does not believe that the EPA should be regulating them,” Romney spokeswoman Andrea Saul, who previously worked on global warming denier Carly Fiorina’s gubernatorial campaign, told Politico. “CO2 is a naturally occurring gas. Humans emit it every time they exhale.” Breathing, unlike the burning of fossil fuels, is carbon neutral. Most pollutants regulated by the EPA — including ozone, nitrogen oxide, particulate matter, and sulfur dioxide — are also naturally occuring, and are dangerous because of the huge quantities produced by industrial activity.