A 36-year-old piano teacher can no longer get through concertos and etudes memorized years ago.
A young mother and office manager finds herself struggling with simple math, and she's forgotten to pick up kids in her carpool.
And a Maryland fire official wakes up exhausted every morning, his head aching. He blames job stress.
FOR THE RECORD - The maximum level of carbon monoxide permitted in the workplace by the Occupational Safety and Health Administration was misstated in a Page 1A article Monday. The correct current limit is 50 parts per million, averaged over eight hours.
The Sun regrets the error.
All three, it turns out, were the victims of chronic exposures to low levels of carbon monoxide.
Long feared as a quick and stealthy killer, carbon monoxide - in long exposures, and in concentrations once thought too low for concern - is now suspected as the cause of significant, even permanent injury to the brain and heart.
Its victims can be anywhere. In the suburbs of Maryland and across the country, carbon monoxide seeps into new tract homes when commuters warm up their cars in the garage, or is drawn back into the house from the furnace flue when someone flips on a bathroom exhaust fan.
And it is seen as a particular threat in cities like Baltimore, where financially strapped families may rely on a neglected furnace for heat or turn on the gas stove for warmth when the oil tank is drained.
"There is no question there are a sizable number - probably tens of thousands of dwellings - in the city that have potentially dangerous heating systems," says Baltimore Heath Commissioner Peter L. Beilenson.
David G. Penney, a physiologist and carbon monoxide researcher at Wayne State University in Detroit, says, "There probably is no lower limit for the safe effects of carbon monoxide."
Penney and a growing number of researchers suspect that this "occult," or hidden car bon monoxide poisoning, may underlie many complaints of persistent asthma, depression, chronic fatigue and chest pain. Behavioral and mood changes, or learning, memory and concentration problems may also be caused by carbon monoxide. Studies have also linked it to low birth weights and heart failure.
The health threats from these chronic, low-level exposures remain an unsettled area of research. Scientists working on the question agree that more studies are needed. But they're confident they're on to something.
"I feel it is a much larger public health problem than anyone has any concept of at present," says pharmacologist Mary A. McCormick, director of the Connecticut Poison Control Center.
Insidious poison
Lloyd Ceccato certainly had no idea his health was at risk from a gas he could neither see nor smell. But he knew something was wrong.
