Formaldehyde Exposure Boosts ALS Risk

Exposure to formaldehyde may increase the risk of developing amyotrophic lateral sclerosis (ALS) or Lou Gehrig’s disease (because in 1941 it killed the New York Yankees baseball player), a study released on Wednesday concluded.

According to the ALS Association, abut 5,600 people in the United States are diagnosed with ALS each year.

ALS is a progressive neurodegenerative disease that affects nerve cells in the brain and the spinal cord. The degeneration of the motor neurons in ALS eventually leads to death. When the neurons die, the ability of the brain to initiate and control muscle movement is lost, resulting in paralysis.

Researchers from Harvard School of Public Health, led by Marc Weisskopf, PhD, examined the link between ALS and 12 types of chemicals. Their study initially focused on the effect of pesticides and herbicides, but later they discovered that formaldehyde increased the risk for developing the disease.

Formaldehyde is a reactive chemical that has been recognized as a human carcinogen. The chemical is found in building materials, smoking, household products, and the use of un-vented, fuel-burning appliances, like gas stoves or kerosene space heaters. At levels above 0.1 parts per million, the exposure causes a burning sensation in the eyes, nose and throat; nausea; coughing; chest tightness; wheezing; and skin rashes.

The study, spreading between 1982 and 1997, analyzed over one million people participating in the Cancer Prevention Study II of the American Cancer Society for their exposure to 12 types of chemicals including formaldehyde. The participants were questioned about the levels of formaldehyde exposure. Those regularly exposed to the chemical were 34 percent more likely to develop ALS compared to those exposed to other chemicals.

“Although this finding could well be a chance observation, it merits further investigation, particularly because people with longer exposure to formaldehyde had a greater risk of developing ALS than those with shorter exposures. People who reported 10 or more years of exposure were almost four times as likely to develop ALS as those with no exposure,” said Dr. Weisskopf.

During the 15-year follow-up, a total 617 men and 539 women died from ALS.

The findings were presented at the American Academy of Neurology 60th Anniversary Annual Meeting in Chicago, last week.