The latest mine disasters have focused attention once again on the perils of coal mining--especially the risk of carbon monoxide (CO) poisoning.
But carbon monoxide is a concern for all of us. The odorless, colorless gas can be found at low levels in most homes that have fuel-burning furnaces or water heaters, gas dryers or attached garages. It's a product of the incomplete combustion of carbon-based fuels and is present in the exhaust of all internal-combustion engines. According to the Centers for Disease Control, carbon monoxide poisoning contributes each year to an average of 1,091 unintentional deaths and 2,385 suicides in the U.S., where it's the most common type of accidental poisoning, leading to roughly 40,000 emergency- room visits annually.
When people show up at the ER with CO poisoning, their primary symptoms are usually dizziness, nausea, headaches and sometimes unconsciousness--warning signs that the molecule has blocked oxygen from reaching the brain. So the first concern of doctors is usually whether there has been brain damage or other neurological effects.
But carbon monoxide can also damage the heart. A new study in the Journal of the American Medical Association shows that even moderate exposure to CO can put survivors at greater risk of heart disease. Researchers from the Minneapolis Heart Institute Foundation followed 230 patients admitted to the hospital for carbon monoxide poisoning. More than one-third of them suffered heart-muscle injury, and of those, nearly 40% were dead within eight years. "We were surprised that so many of the patients died," says Dr. Timothy Henry, one of the study's authors. "That's three times as high as the normal population."
Luckily, it's not hard to protect yourself and your family from carbon monoxide poisoning. The first step is to install CO monitors in or near every bedroom in your home. Remember also to have your fuel-burning appliances inspected regularly by a qualified technician (once a year if you have an older model). Check fireplaces before you use them to make sure the flue is unobstructed, and don't use charcoal burners indoors. Finally, never start a car in a closed garage or other enclosed space.
Taking a few precautionary steps can mean a safer home--and a healthier heart.
Sanjay Gupta is a neurosurgeon and CNN medical correspondent