What Is Asbestos? A group of six minerals occurring naturally as masses of strong, flexible fibers that can be separated into thin threads and woven are known collectively as asbestos. These heat-resistant fibers were used 4,500 years ago. There is evidence to show that early Finland inhabitants used asbestos to strengthen their pots and cooking utensils and that the Egyptians used asbestos in 2000 BC to make burial shrouds. The first U.S. patent for asbestos was issued in the United States in 1828, and in 1858 Johns-Manville was founded.

The company was one of the first to manufacture products with asbestos and has fought claims for asbestos exposure for decades. The manufacturing company used asbestos to manufacture fire-resistant roofing, then later added asbestos heat insulation, asbestos automotive sheet cylinder packing, asbestos acoustical products, and asbestos cement to their roster of asbestos products. The company also provided many of the asbestos products used to insulate Navy war vessels in 1945, then later became a leading manufacturer of asbestos cement pipe, fiberglass, and PVC pipe.

What Was the Asbestos Cover-up by Johns-Manville? Johns-Manville buried data for decades regarding the dangers of asbestos. As an example, in 1933, Dr. Anthony Lanza who was a full-time employee at Metropolitan life advised a Manville company physician to avoid hanging warning posters in the workplace that informed employees of the health risks associated with asbestos exposure. This was after Lanza’s own research found that after 5-10 years of asbestos exposure, half of all textile workers showed asbestosis on their x-rays, and after 15 years, 87 percent suffered from lung disease. Metropolitan Life also discouraged government inspections of a Manville plant in an effort to conceal the harmful health effects of asbestos.

This cover-up became a way of life with Johns-Manville, and soon other companies that manufactured asbestos products followed suit. Manville’s company president even made it company policy to not inform sick workers about their asbestos-related illnesses, even as they became sicker.  Along the way, in 1918, insurance companies began refusing to sell insurance to asbestos workers, and in 1922, the U.S. Navy lists asbestos work as hazardous. As early as 1943, Dr. LeRoy Gardner called asbestos a “likely carcinogen,” and in 1964 industrial reps reported there was no safe amount of asbestos exposure.

What Are the Dangers of Asbestos? The danger of asbestos lies in the fact that microscopic asbestos particles float in the air, especially during the manufacturing process. These fibers can be inhaled or swallowed, leading to serious health issues. While mesothelioma cancer is the primary result of asbestos exposure, such exposure can also increase the risk of lung cancer, asbestosis, and other cancers such as kidney cancer and larynx cancer.

When the fibers are inhaled, they can lodge in the lining of the lung and chest walls. They inflame the surrounding tissues, eventually leading to mesothelioma cancer in the lungs. When these inhaled asbestos fibers are coughed up then swallowed, the fibers can lodge in the lining of the abdomen, causing peritoneal mesothelioma.  When the cells in the body are damaged by something like asbestos, the DNA of the cell is changed, causing cancerous cells to grow quickly.

Where is Asbestos Found? Until the 1970s, asbestos was widely used, particularly in the automotive industry, shipbuilding, and construction. The following items routinely contained asbestos prior to this time:

• Lab furniture
• Components for electric motors
• Chemical containers for corrosive substances
• Electrical wire conduits
• Transmission, brake, and clutch components
• Cement pipe
• Heating vessels and boilers
• Textiles, including curtains
• A wide variety of insulation products
• Coatings and sealants
• Roofing products
• Pipe coverings
• Paper products

Buildings, ships, and automobiles that were built prior to 1975 may still contain asbestos. Today, asbestos is used in the following products:

• Vinyl tiles
• Brake pads
• Roofing materials
• Cement pipe imported from other countries
• Corrugated sheeting
• Clutches for automobiles

Asbestos has also been found as a contaminant in vermiculite used in potting soils, and in vermiculite home insulation. Vermiculite contaminated with asbestos was still being produced in 1990 from a Libby, Montana mine, then processed at 245 sites around the United States. All vermiculite currently used in potting soil is claimed to be asbestos-free, yet many homes still have vermiculite insulation in their attics.

What is Mesothelioma? Mesothelioma is a relatively rare cancer that is both aggressive and deadly. The primary cause of mesothelioma is exposure to asbestos. At least 8 out of every 10 people diagnosed with mesothelioma have been exposed to asbestos, usually in their workplace or home. When asbestos fibers are breathed in, they travel to the ends of the small air passages, reaching the pleura where they lodge in the tissues, causing inflammation and scarring.

The mesothelium is the membrane that covers and protects most of the internal organs and is composed of two layers of cells: one layer surrounds the organs, the other forms a “sac” around it. The mesothelium produces a lubricating fluid between these two layers of cells, allowing the organ to easily “glide” inside the body. Asbestos fibers attack the mesothelium, primarily in the lungs, but also in the abdomen (when asbestos fibers are coughed up, then swallowed), the heart, and the testes.

What Are the Different Types of Mesothelioma? As noted above, there are four types of mesothelioma. Pleural (lung) mesothelioma makes up at least 75 percent of all mesothelioma cases. Peritoneal (abdominal) mesothelioma is the next most common type of mesothelioma, followed by pericardial (heart) and testicular (testes). As many as 10 percent of all those individuals that have had heavy, prolonged exposure to asbestos will develop pleural mesothelioma. Symptoms of mesothelioma may not manifest until 20-40 years following the asbestos exposure after the tumors have grown and spread.

What Are the Risk Factors for Mesothelioma? Exposure to asbestos is by and large the leading cause of mesothelioma. In about 80 percent of all cases of mesothelioma, there is a history of asbestos exposure at work. A history of smoking along with asbestos exposure does not appear to increase the risk of mesothelioma but does significantly increase a person’s risk of developing lung cancer.

There have been a few published reports of mesothelioma cancers developing as a result of high doses of radiation to the chest or abdomen as a treatment for another type of cancer. A few small studies have raised the question as to whether the simian virus 40 (SV40) could potentially increase the risk of developing mesothelioma, but most experts agree we simply do not have enough research to determine whether this is true.

Age is a factor, but largely because it can take 40 years for asbestos exposure to result in symptoms that lead to a mesothelioma diagnosis. While mesothelioma is more common among men, this is likely due to the fact that many more men work in high-risk industries. For reasons not well understood, mesothelioma tends to strike white and Hispanic individuals more often than Asian American or African American individuals.

How Common is Mesothelioma? Mesothelioma is relatively rare, with about 3,000 people being diagnosed each year. The number of people who are diagnosed each year with mesothelioma across the United States has begun to decrease slightly (as opposed to consistently increasing throughout the past four decades).

Who Gets Mesothelioma? The “typical” mesothelioma patient is male, over the age of 65 (the average age is 72), with a military background or a blue-collar background. Occupations such as manufacturing, firefighting, construction, ship building, military service, power generation, and chemical refining all increase the likelihood of a person developing mesothelioma.

What Are the Typical Symptoms of Mesothelioma? Symptoms of mesothelioma will vary depending on where the mesothelioma is located (lungs, heart, abdomen, or testes). For pleural (lung) mesothelioma, patients may experience loss of appetite, anemia, abdominal swelling or tenderness, chest pain, fatigue, difficulty breathing, pain, night sweats, lumps under the skin of the chest or the skin of the abdomen, chills, cough, coughing up blood, fever, fluid buildup, wheezing, weight loss, vomiting, and shortness of breath.

Abdominal mesothelioma has many of the same symptoms with additional symptoms of bowel obstruction, a constant feeling of fullness, and hernias. Pericardial mesothelioma can additionally have the following symptoms: heart murmur, pressure of the heart, irregular heartbeat, and heart failure.

How is Mesothelioma Diagnosed? Because the symptoms of mesothelioma are so similar to a number of other conditions, diagnosing the illness can be difficult. The patient’s medical history is reviewed, particularly any history of asbestos exposure. Lung function tests and chest or abdomen x-rays, along with a CT scan or MRI may be helpful to diagnose mesothelioma. A biopsy will be necessary to confirm a diagnosis of mesothelioma.

If the mesothelioma cancer is in the chest, the doctor may perform a thoracoscopy which allows the physician to look inside the chest and obtain tissue samples. If the cancer is believed to be in the abdomen, a peritoneoscopy may be done. The doctor will stage the mesothelioma cancer after the diagnosis to determine how advanced it is, and whether it has spread beyond the membrane surface to other parts of the body.

What Are the Survival Rates of Mesothelioma? The five-year survival rate for mesothelioma is about ten percent, meaning that ten percent of all those diagnosed with mesothelioma will live at least five years following their diagnosis. If the mesothelioma cancer is found early and is localized, that number increases to eighteen percent. If the cancer is found late and has spread to distant parts of the body, the five-year survival rate is only about 7 percent. A person’s age at diagnosis makes a difference in the survival rate, and those who are able to receive surgery usually have a higher rate of survival. Mesothelioma is a complex cancer with few physicians trained and experienced enough to treat the disease.

What Are the Most Common Treatments for Mesothelioma? More than 80 percent of mesothelioma patients will receive chemotherapy for their illness—a 2016 study showed chemotherapy tripled the survival rate of those diagnosed with pleural or peritoneal mesothelioma. Surgery and radiation therapy may also be treatments for mesothelioma, although less than 20 percent of pleural mesothelioma patients will qualify for aggressive, tumor-removing surgery. Improved survival rates have been seen when two or more treatments are combined.