The primary risk factor for mesothelioma is past asbestos exposure. Older men who worked in industries with asbestos have the highest risk of receiving a mesothelioma diagnosis. Other risk factors for mesothelioma include exposure to different minerals and genetic factors.
Risk Factors vs. Causes
When discussing risk factors for a disease like mesothelioma, it is important to understand the difference between risk factors and causes:
- A risk factor can be used to determine which populations are more likely to develop mesothelioma.
- Each risk factor may or may not be a contributing cause.
For example, being a man is not a cause of mesothelioma, but men are more likely to develop the disease. Being male is a risk factor for the disease.
Asbestos exposure, on the other hand, is a risk factor but may also be a cause. Tiny asbestos particles in the airways can actually cause later tumor growth.
What Is the Main Cause of Mesothelioma?
Asbestos exposure is the leading risk factor for mesothelioma.[1] More than any other population, regardless of factors like age and gender, people exposed to asbestos are more likely to develop mesothelioma.
Asbestos is also considered the leading cause of mesothelioma, but pinpointing the cause of any cancer is difficult. Not everyone exposed to asbestos gets mesothelioma, and some who have the diagnosis never encountered asbestos.[1]
What Are the Chances of Getting Mesothelioma from Asbestos Exposure?
Despite heavy asbestos use in the past, mesothelioma is a rare cancer. While it is the leading risk factor, most people exposed to asbestos never develop mesothelioma.[1]
Still, experts agree that there is no safe level of exposure. Asbestos can cause other health problems in addition to cancer. Avoid asbestos if possible, and talk to your doctor if you think you have been exposed.
How Much Asbestos Exposure Causes Mesothelioma?
There is no definite answer to this question, unfortunately. However, the risk of developing mesothelioma increases when exposed to asbestos early, in large amounts, or for prolonged periods. Although asbestos is a leading risk factor, it cannot be considered a definite cause, and it may not be the only factor.
Who Typically Gets Mesothelioma? Risk by Age, Gender, and Occupation
Other important risk factors for mesothelioma are likely related to asbestos. Being older, male, and working in certain occupations are all risk factors.
Older men are most often diagnosed with mesothelioma, probably because men more commonly work in industries that used asbestos. Age is a factor because mesothelioma takes decades to develop.[1]
Jobs and workplaces that put people at risk for mesothelioma include:
Asbestos was used in many aspects of construction, including insulation, roofing, flooring, plumbing, electricity, and many other applications. People who worked in construction with these materials or in factories that manufactured them risked developing mesothelioma.
Non-Occupational Asbestos Exposure
Some patients with mesothelioma seem to have no past asbestos exposure until non-occupational sources are considered. The workplace is not the only location where people encounter asbestos.
Secondhand Asbestos Exposure
Workers often carried asbestos fibers home on their clothes and skin. Family members could have been exposed to those fibers as a result. This often accounts for cases of mesothelioma in older women who did not work around asbestos.
Secondhand exposure has been proven in lawsuits. In 2022, a jury awarded Deanne Warren $43 million because she developed mesothelioma as a result of her husband’s jobs.
He worked as a carpenter and contractor during the 1970s and 1980s. Warren was exposed to asbestos fibers when she did his laundry.[2]
Environmental Asbestos Exposure
Environmental exposure is another way people can be exposed to asbestos. It exists naturally in the ground. Where there are deposits, construction and road projects can churn up asbestos fibers, exposing people who live in the area.
People who live near job sites that used asbestos could also have suffered exposure. An example of environmental asbestos exposure occurred in Libby, Montana.
W.R. Grace mined vermiculite in the area, which later was found to be contaminated with asbestos. Mine workers were most at risk of exposure, but the disturbed asbestos also harmed area residents.[3]
Smoking and General Health with Asbestos Exposure
Mesothelioma is not guaranteed to develop after asbestos exposure; however, other risk factors may increase the odds of developing the cancer. Smoking is a significant factor because it is also carcinogenic.
Smoking alone is a significant risk factor for lung cancer. For those exposed to asbestos, smoking increases the risk of developing this disease. Other health factors may also contribute, such as being overweight, not exercising, or eating a poor diet.
What Causes Mesothelioma Other Than Asbestos?
Asbestos is the leading cause and risk factor for mesothelioma, but there are others. Experts know there must be other factors because some patients never encountered asbestos. Additional risk factors may include minerals other than asbestos, a virus, radiation, and genetics.
Zeolites and Erionite
Another group of minerals, called zeolites, have been implicated in mesothelioma. Epidemiological studies of people in a certain region of Turkey have found high rates of mesothelioma, yet no asbestos exposure.
What is abundant in the region are zeolites, including one type of zeolite called erionite.[1] Studies have found that laboratory animals exposed intentionally to the fibers of these minerals develop mesothelioma.[4]
The SV40 Virus
A controversial potential risk factor for mesothelioma is a virus called SV40. This virus, found naturally in monkeys, also contaminated a significant proportion of polio vaccines in the 1950s and 1960s.
Thousands of people were exposed to the virus through this vaccine, and there is some research evidence that it could contribute to mesothelioma.[1]
While some experts and most government health officials deny SV40 is a risk factor for mesothelioma, the evidence is compelling.
Many studies have found that the virus is present in tumor samples of patients with mesothelioma. How it may contribute to cancer formation is not understood, but it may be an important risk factor.
Genetic Factors
Finally, a genetic component may explain why some people develop mesothelioma without ever encountering asbestos. There may be certain genes that increase the risk of developing mesothelioma.
One recently discovered gene was named BAP1. A study of two families with a long history of mesothelioma and other cancers found that these individuals had a mutation in the BAP1 gene. The research also indicates people with this mutation, who are also exposed to asbestos, are at an even greater risk.[5]
Other gene mutations, including those in CDKN2A and NF2, have been implicated as risk factors for mesothelioma. These, along with BAP1, may play a role in cancer formation because they are tumor suppressor genes. A mutation interferes with the ability of the body to suppress or prevent tumor growth.[5]
Radiation Exposure
High-energy radiation damages DNA and is a known cause of cancer in general. Exposure to radiation could be a factor in developing mesothelioma.
Radiation therapy to the chest or abdomen for other cancers could trigger pleural or peritoneal mesothelioma.
The accumulation of radiation exposure through diagnostic X-rays might also play a role in mesothelioma. Of particular concern is a radioactive substance called thorium dioxide. While not used today, it was a component of X-rays used from the 1920s through the 1950s.[6]
How Can I Lower My Risk for Mesothelioma?
It is possible to lower your risk for mesothelioma by addressing and changing risk factors you can control, such as lifestyle habits. The most important way to reduce risk is by avoiding asbestos. If you live in an older home or work in an older building, find out if they contain asbestos.
Asbestos in your home can be abated or encapsulated by licensed professionals. If you have asbestos in your workplace, talk to your employer about the risks and what can be done to mitigate them. Contact the Occupational Safety and Health Administration (OSHA) if you believe your employer is violating asbestos safety standards.
What if I Have Risk Factors for Mesothelioma?
If you have risk factors, especially asbestos exposure, talk to your doctor. They can help you decide if you need a mesothelioma screening and refer you to an oncologist and other specialists.
The earlier you get a diagnosis of mesothelioma, the better the outcome. This is an aggressive cancer that gets more difficult to treat as it advances. Recognize risk factors, take steps to reduce them, and seek a diagnosis as soon as possible.
Risk factors are like guidelines. They are not causes of mesothelioma and cannot guarantee a person will develop the disease. They tell us that certain populations have an increased chance of developing the disease.
This is important because it improves regulations and advocacy for at-risk people. It is also important because it provides awareness for those with these risk factors. If you have risk factors for mesothelioma, be proactive and receive regular screening to increase the odds of early detection.
