In a new study released by Harvard, researchers suggest that truck drivers and others who work closely with diesel fumes on a regular basis are at greater risk for developing amyotrophic lateral sclerosis. Drivers Could Be at Risk Even Years Later The increased risk could be as high 40 percent when compared against men with no such exposure, said study author Aisha Dickerson. She’s a postdoctoral research fellow with the Harvard T.H. Chan School of Public Health in Boston. “The strongest association we saw was for occupations that were held at least for 10 years prior to their ALS diagnosis,” Dickerson said. “Someone could have been exposed years earlier, before they showed any symptoms of ALS, but the damage would have been done long ago.” Jobs with a lot of diesel exhaust exposure include truck drivers, police officers, shipyard hands, construction workers, farm laborers and tool operators, as well as many people who work in an industrial setting, Dickerson said. What is ALS? ALS, also known as Lou Gehrig’s disease, is a neurodegenerative condition in which the nerve cells responsible for controlling muscle movement wither and die. Patients eventually lose their strength and their ability to walk, move, speak, eat and even breathe. There is no cure, according to the U.S. National Institutes of Health. Prior studies have suggested a higher risk of ALS in specific jobs that are commonly exposed to diesel fumes, such as truck and bus drivers, construction workers and military personnel, Dickerson said. The recent ice bucket challenge was done to help fund research for an ALS cure.
Early Symptoms Early symptoms of ALS usually include muscle weakness or stiffness. Gradually all muscles under voluntary control are affected, and individuals lose their strength and the ability to speak, eat, move, and even breathe. Most people with ALS die from respiratory failure, usually within 3 to 5 years from when the symptoms first appear. However, about 10 percent of people with ALS survive for 10 or more years. Toxins and Genetics It’s possible that the toxins in diesel fuel are affecting people’s genetics in ways that spur on ALS, said Dr. Anthony Geraci, director of the neuromuscular center at Northwell Health in Manhasset, N.Y. But at least 20 genes have been linked to ALS, and “this clearly is a genetic disorder in a large percentage of individuals with ALS,” Geraci added. “Perhaps those jobs and diesel exhaust and whatever might be in the diesel is hastening a disease that already may be genetically programmed in the individual,” Geraci said. Study Limited To Men This risk increase was only seen in men, however, and the study did not prove that diesel exhaust caused ALS. Diesel exhaust contains a variety of toxic compounds, including carbon dioxide, carbon monoxide, nitrogen oxides, sulfur compounds, formaldehyde, benzene and methanol, the NIH says. Further Research Needed Further research is needed to more definitively link diesel fumes and ALS, Dickerson said.