Public health scientists are raising concerns that people using off-road vehicles (ORVs) across the country may be exposing themselves to naturally occurring asbestos fibers, according to a recent study.
ORVs, which include all-terrain vehicles, four-wheel-drive vehicles and off-road motorcycles, are made for rugged riding, and they often churn up clouds of dust.
That dust can be deadly if it contains toxic erionite or asbestos fibers.
“ORV use in geographic regions with naturally occurring asbestos may result in the liberation of these minerals from underlying rocks and soil, which may put ORV participants at risk to potentially hazardous inhalation exposures,” the study concluded. “Public health measures are recommended to communicate the possible dangers.”
In their study, scientists found that almost 80 percent of the trails used by ORVs in California, Arizona, Colorado, Nevada and Utah, were within 20 miles of substantial asbestos deposits. Almost one-third of the trails are within a mile of those deposits.
The study was published recently in the International Journal of Hygiene and Environmental Health.
“This puts riders — particularly children — at risk of inhalation exposure,” lead author Dr. Chris Wolfe, an epidemiologist at Cincinnati Children’s Hospital Medical Center, said in a press release.
The research included material from 15 previous studies that involved ORV trails and deposits of these potentially dangerous fibers.
The inhalation or ingestion of microscopic asbestos fibers can lead to serious health issues, including mesothelioma cancer.
An earlier study estimated that 44 million Americans had engaged in recreational activities involving ORVs within the previous year.
Public health awareness and past epidemiologic studies involving ORVs often focused on injuries and deaths sustained from their use, not the dangers of inhaling dust.
This study did not detail the number of ORV users who have experienced negative health outcomes. It did call for further study to determine prevalence of asbestos-related disease among ORV users.
“Off-roading in areas with NOA (naturally occurring asbestos) or NOE (naturally occurring erionite) presents a nontraditional route of exposure that has not been sufficiently explored,” Wolfe wrote. “Public health initiatives should concentrate on increasing awareness of these risks.”
Most asbestos exposure in the U.S. is work related. Occupational exposure is the primary cause of mesothelioma cancer and other asbestos diseases. There are documented cases, though, of secondary and environmental exposure.
Libby, Montana, for example, is the best-known case of nonoccupational exposure. Asbestos dust that traveled several miles from the nearby vermiculite mines has killed or sickened hundreds of people who never worked there but lived nearby.
In the past, regulatory agencies have shown concern with the potential problem for ORVs in certain areas. The U.S. Bureau of Land Management in 2008 ordered an emergency closure of parts of the Clear Creek Recreation Area in California, popular among ORV users, because of the region’s large asbestos deposits.
Congress is moving to lift that closure.
Most of the large asbestos deposits within the U.S. are along the Appalachian Mountains (spread across 18 eastern and southern states) and various mountain ranges in the west and southwest parts of the country.
Researchers identified 655 mineral fiber occurrences in the five-state area of highest asbestos concentration. Of those occurrences, 241 were located within a five-mile radius of an ORV trail, and 150 were within a mile of a trail, according to the study.
In total, researchers identified 3,745 miles of trails within range of an asbestos deposit.
Researchers also believed that children are at higher risk of serious problems because their breathing zone is closer to the ground where asbestos exists, and their lungs are not yet fully developed.
The long latency period between exposure and diagnosis of asbestos disease (10-50 years) also makes children more likely to experience problems during their lifetime.
Researchers also raised the issue of secondhand exposure, which is when riders inadvertently carry the mineral fibers trapped on their clothes, hair, shoes and vehicles to their homes, potentially exposing others who were not using the ORVs.