http://www.skepticalscience.com/breathi ... ioxide.htm http://www.skepticalscience.com/breathi ... ioxide.htm http://www.skepticalscience.com/breathi ... ioxide.htm http://www.skepticalscience.com/breathi ... ioxide.htm occasional http://www.skepticalscience.com/breathi ... ioxide.htm http://www.skepticalscience.com/breathi ... ioxide.htm "Breathing contributes to CO2 buildup" occasional carbon http://www.skepticalscience.com/breathi ... ioxide.htm http://www.skepticalscience.com/breathi ... ioxide.htm http://www.skepticalscience.com/breathi ... ioxide.htm occasional http://www.skepticalscience.com/breathi ... ioxide.htm http://www.skepticalscience.com/breathi ... ioxide.htm http://www.skepticalscience.com/breathi ... ioxide.htm http://www.skepticalscience.com/breathi ... ioxide.htm http://www.skepticalscience.com/breathi ... ioxide.htm stop breathing http://www.skepticalscience.com/breathi ... ioxide.htm http://www.skepticalscience.com/breathi ... ioxide.htm stop breathing http://www.skepticalscience.com/breathi ... ioxide.htm stop breathing http://www.skepticalscience.com/breathi ... ioxide.htm http://www.skepticalscience.com/breathi ... ioxide.htm http://www.skepticalscience.com/breathi ... ioxide.htm carbon http://www.skepticalscience.com/breathi ... ioxide.htm carbon carbon