CINCINNATI, Oct. 8 (UPI) -- U.S. researchers warn ultra-fine air particles -- invisible but inhaled into the deepest parts of the lungs -- may be increasing firefighters' heart risk.
Researchers at the University of Cincinnati Academic Health Center say ultra-fine air particulates are harmful and predispose firefighters to heart disease -- the greatest killer of U.S. firefighters.
The study, reported in the Journal of Occupational and Environmental Medicine, finds more than 70 percent of particulates released during fires are "ultra-fine." The researchers -- who measured breathable particulates as emitted in every phases of fighting simulated house and automobile fires -- found levels highest in the "overhaul phase," when firefighters prevent ignition of partially burned material.
"Firefighters simply can't avoid inhaling these ultra-fine particles when they are not wearing their protective breathing apparatus and, unfortunately, they routinely remove it during overhaul," researcher Stuart Baxter at the University of Cincinnati says in a statement.
Baxter says firefighters typically shed the standard air tank, which only lasts about 20 minutes, and other heavy gear during "overhaul." He suggests ultra-fine exposure could be avoided through equipment improvements and more rigid safety protocols, such as having additional workers who could be rotated to reduce the burdens of the job.