HealthDay News — Those continuously exposed formaldehyde, such as embalming fluid, are three times more likely to develop amyotrophic lateral sclerosis (ALS), compared to those never exposed to the chemical, according to a study published in the Journal of Neurology Neurosurgery & Psychiatry.
Previous animal studies have linked formaldehyde to the development of ALS, according to background information in the study. Using U.S. Census data gathered on almost 1.5 million adults, Andrea Roberts, PhD, MPH, a research associate at Harvard University’s T.H. Chan School of Public Health in Boston, and colleagues examined a possible link between ALS and occupational exposure to formaldehyde. When they were 25 or older, participants in this survey were asked about their current or most recent job. The research team estimated people’s on-the-job exposure to formaldehyde using criteria developed by the U.S. National Cancer Institute. They then used death records to track deaths caused by ALS.
The researchers found that men with a high probability of formaldehyde exposure were about three times as likely to die of ALS as those who had never been exposed to the chemical. That risk increased even more among men who likely were exposed to large quantities of formaldehyde very often. All men with high-probability, high-intensity exposure were funeral directors, according to the study.
Women with a high probability of exposure did not have an increased risk of ALS. Perhaps too few had jobs that exposed them to high levels of formaldehyde, making it difficult to calculate risk level, the researchers said.
The authors warned that this study does not show a cause-and-effect link between formaldehyde exposure and ALS risk, noting that funeral directors might have a higher risk because of other embalming chemicals or even bacteria or toxins carried on the bodies they prepare.