CO can only be detected with a CO detector
2) Produced from incomplete combustion:
CO comes from burning any fuel containing carbon, including natural gas, oil, kerosene, gasoline, coal, wood, tobacco, and even incense.
Most outdoor exposure comes from vehicle exhaust (gasoline engines with cold or defective catalytic converters produce 10,000-40,000 parts per million (ppm), but under 200ppm when hot and working properly).
Most indoor exposure comes from gas appliances, especially unvented ovens and ranges, and backdrafting water heaters.
3) The largest component of air pollution:
More tons of CO are released annually in USA from human sources than from all other EPA criteria air pollutants and hazardous toxic chemicals combined.
4) A dangerous and deadly poison:
CO is the #1 cause of unintentional toxic deaths and poisonings in USA every year. While exposure to high levels is fatal within minutes, chronic exposure to low levels has been shown to both cause and exacerbate many serious medical conditions, including strokes, heart attacks and asthma attacks.
Most at risk are fetuses and newborn infants, whose risk of low birth weight, birth defects, and respiratory mortality increases significantly with each 1ppm increase in ambient CO exposure during critical time periods in pregnancy and early life.
5) Vital to human life:
CO is produced continuously in all mammals from the routine breakdown of heme proteins (hemoglobin, myoglobin, neuroglobin, etc) by heme oxygenase and bioactive in over 100 critical pathways, including as a sensory neurotransmitter.
Humans quickly make more CO in response to stress of any kind--including sensory, physical, infectious, and even mental stress--and this CO can be easily measured in exhaled breath. Women also make 3 to 5 times more CO during the premenstrual phase of their cycle,