Question: Can long-term exposure to carbon monoxide hurt me?
This is probably the most common question we get here at About.com First Aid. In most cases, people are concerned about appliances leaking carbon monoxide into the home over a long period of time. What kind of damage can occur and does it cause long-term effects?
Answer: Yes, exposure to carbon monoxide over a long period can make you sick -- or even kill you.
Carbon monoxide poisoning is the most common type of poisoning worldwide. Carbon monoxide is a gas that you cannot taste, smell or see. It comes from incompletely burning gas, wood, propane, or a number of other fuels. Carbon monoxide is present in smoke, motor exhaust and smog, just to name a few.
Carbon monoxide blocks oxygen from getting to the places it needs to get in the bloodstream. Red blood cells, which usually carry oxygen, consider carbon monoxide way more sexy than oxygen and are 210 times more attracted to it. Victims of carbon monoxide poisoning die from not getting enough oxygen to their hearts and brains.
How Do I Know If I'm Sick?
Carbon monoxide poisoning is hard to diagnose. The symptoms of carbon monoxide poisoning look a lot like the flu -- headache, body aches, fatigue, nausea -- but without a fever. This insidious gas affects each person a little differently, so unless healthcare providers suspect carbon monoxide poisoning, they're likely to overlook it.
Levels of carbon monoxide in the blood are easy to measure, but drop rapidly. Just a few hours after starting to breath fresh air, victims' blood levels of carbon monoxide can be quite low. The only way to diagnose carbon monoxide poisoning is to interview the victim; do a good physical assessment; and suspect it for some reason. It's easier to recognize carbon monoxide poisoning when more than one person in the home (or the school, the office, the car, etc.) also show symptoms.
Can I Still Be Sick and Not Look It?
In cases where the first sign of trouble is finding the presence of carbon monoxide before anyone shows symptoms of poisoning, it's natural to wonder what -- if any -- damage has been done. Unfortunately, there isn't really an answer to that question yet. I was unable to find any published studies that tried to identify symptoms in people who were exposed to carbon monoxide but didn't complain of anything. We know carbon monoxide affects heart and muscle function in high and low concentrations, but we don't know if there is any long-term damage from long exposure to low levels.
Let me state that again. Carbon monoxide exposures too low to cause symptoms may damage the body; we just don't know how much or in what way.
There is growing evidence that carbon monoxide poisoning bad enough to send you to the hospital leads to problems up to a year later. Currently, there are no specific treatments for the after effects of carbon monoxide poisoning. Physicians just try to treat the symptoms one by one until more research is done. Until then, paying attention to your mind and body is the best defense. Well, that and buying a carbon monoxide detector.
Adir, Y., et al."Effects of exposure to low concentrations of carbon monoxide on exercise performance and myocardial perfusion in young healthy men." Occupational and environmental medicine. Aug 1999 PMID: 10492650.
Annane, D., et al."Prognostic factors in unintentional mild carbon monoxide poisoning." Intensive care medicine. Nov 2001 PMID: 11810122.
Hardy, K.R., and S.R. Thom. "Pathophysiology and treatment of carbon monoxide poisoning." Journal of toxicology. Clinical toxicology. 1994 PMID: 7966524
Henry, C.R., et al."Myocardial injury and long-term mortality following moderate to severe carbon monoxide poisoning." JAMA. 25 Jan 2006 PMID: 16434630.
Jasper, B.W., et al."Affective outcome following carbon monoxide poisoning: a prospective longitudinal study." Cognitive and behavioral neurology. Jun 2005 PMID: 15970733.
Prockop, L.D., and R.I. Chichkova. "Carbon monoxide intoxication: an updated review." Journal of the neurological sciences. 15 Nov 2007 PMID: 17720201.