Road machine operators are operating engineers who specialize in road grading and road construction. Exposure to asbestos in this field is primarily due to asbestos naturally occurring in the roadbed gravel, or from asbestos intentionally added to road material to strengthen it.
Asbestos in Dirt Roads
While dirt and gravel roads in the eastern part of the United States are increasingly rare, in the western United States they are common. This can be a particular problem in dry areas where traffic can throw plumes of dust into the air. The dust can contain asbestos, which is then blown away from the road and creates a hazardous zone.
In 2005, California began the process of paving dirt roads as a result of recommendations of a study that found asbestos could be detected more than 200 feet from the road itself. Even when no obvious dust was being raised by traffic, the asbestos contamination was still detectable.
Serpentine, California's state rock, seems to be the cause of the contamination. The rock is found in 44 of 48 California counties and contains chrysotile asbestos. Whether incorporated into the gravel used for the road, or simply as part of the landscape that is graded for road building, asbestos is ejected into the air when road construction equipment - such as graders - or traffic passes over it.
Studies done for the State of California now show that there is a significant increase in the likelihood of developing asbestos-related cancer for any people regularly within 190 feet of a gravel or dirt road.
Even in the case of roads not naturally infused with serpentine, imported gravel can also contain asbestos. When excavating rock at a gravel pit, it is not uncommon to encounter seams of asbestos that are then included in the gravel. While this has been regulated in recent years and new gravel must be screened for asbestos, any construction or demolition of older roads will turn up traces, putting road machine operators at even greater risk.
Dangers at Work
It is widely understood that some occupations are more likely to result in workplace injuries than other ones. Even so, people in today's society expect worker safety to be an important priority of employers, overseen by government agencies. Unfortunately, even in recent history, this was not always the case in terms of asbestos exposure, and employees were placed in situations that places their health at risk.
Asbestos and Its Health Effects
There are two major types of asbestos. Chrysotile, sometimes called "white" asbestos, is the only member of the serpentine category and was the kind most commonly utilized. It is a relatively soft variety that is not normally associated with mesothelioma or asbestos cancer. Irritation to the interior surfaces of the lungs can happen if chrysotile fibers are inhaled, however. Asbestosis may then be the result when scar tissues accumulate in the lungs.
The second category is called amphibole asbestos; it is considered more dangerous. Lung cancer and pleural mesothelioma, an unusual but frequently fatal cancer affecting the mesothelium (the tissue that lies between the lungs and the chest cavity), are the most common cancers to result from being exposed to amphibole asbestos. More unusual types of mesothelioma include peritoneal and pericardial mesothelioma; these cancers are also caused by extensive contact with amphibole asbestos.
Why Asbestos Was Used
Asbestos was generally used to safeguard people's lives. When it comes to insulating against flames and temperature extremes, few things can equal asbestos, especially the serpentine form. Amphibole forms of asbestos had additional traits that made them useful in industrial situations. For instance, amosite, also known as "brown" asbestos, has a high iron content, making it resistant to caustic chemicals. "Blue" asbestos, or crocidolite, was commonly found on electrical equipment since it is highly resistant to electricity. ACMs (asbestos-containing materials) that could protect people and property against combustion, extreme temperatures, electrical contact and chemical burns could be formed by combining multiple types of fibers.
Asbestos did not pose a health hazard while it remained solid. However, as ACMs aged, they were prone to becoming friable (i.e., easily reduced to powder by hand pressure alone). When they are friable, asbestos particles are easily released into the air, where they can be easily inhaled or ingested and thereby cause health problems. Unless strict decontamination policies, such as using on-site uniforms and showers, were enforced, it was common for personnel to bring home asbestos dust on themselves or their clothing, exposing even more people to danger.
A Ticking Bomb
As opposed to many work-related injuries, which are easily observed and known about immediately following the causing incident, asbestos-related illnesses can take ten, twenty, or even thirty years to develop. The symptoms of asbestosis and mesothelioma - pain in the chest, dyspnea and chronic coughing - may easily be confused with the symptoms of other, less serious disorders. Especially with mesothelioma, the earlier the diagnosis, the higher the odds of surviving or at least of improved quality of life. Men and women who worked as road machine operators, and those who resided with them, should therefore notify their doctors about the chance of asbestos exposure. Even though mesothelioma survival rate is generally low, yet early diagnosis and treatments like mesothelioma radiation can improve the prognosis for this disease.Sources
Bowker, Michael. Fatal Deception: The Untold Story of Asbestos (New York: Touchstone, 2003)
California Environmental Protection Agency - Department Releases Garden Valley Study: Recommends Re-Surfacing of Asbestos Containing Roads
University of Wisconsin - Asbestos Containing Material (ACM) - Laboratories and Shops
University of Wisconsin - Asbestos Disposal