Asbestos: History, Types, and Health Risks of Mesothelioma

What Is Asbestos?

Asbestos is a naturally occurring mineral found in soil. It has tiny fibers, or strands, that stick and weave together. Asbestos is usually located in soil or attached to rocks. Asbestos fibers look like fragments of cloth.

Humans began using asbestos more than 5,000 years ago. Records depict ancient Egyptians blaming asbestos for a worker’s illness. Only in the last 40-50 years did the general public learn that asbestos was a health hazard.

The use of asbestos in the United States started during the 19th century. It spiked during World War II as industrial production increased. The use of asbestos reached a peak in the 1970s, which is around when scientists began alerting the public to the health risks caused by asbestos exposure.

History of Asbestos

Asbestos was first discovered during the Stone Age, when it was used to make pots. The naturally occurring mineral maintained relevancy for thousands of years, with records from 300 B.C. of Egyptians mining for asbestos. During the late 1800s and early 1900s, asbestos use started booming and reached a peak during the 1940s for World War II when it was used to build military ships and aircraft. The mineral, which was prized for durability and resistance to heat, became a central component of houses, offices and other buildings during the 1950s, 1960s and 1970s.

By the 1980s, the public became aware that asbestos was harmful when inhaled or ingested. Scientists directly tied asbestos exposure to deadly cancers such as mesothelioma and lung cancer. As manufacturing companies that profited for years off of asbestos began facing lawsuits, alternatives emerged and asbestos lost its footing as a popular part of American Industrialism. Mining for asbestos stopped at the beginning of the 21st century.

In 2024, the U.S. Environmental Protection Agency banned the use of chrysotile asbestos, which at the time was the only type still imported and used for select industries.

What Was Asbestos Used for?

Prior to the last couple decades in the 20th century, asbestos was a sacred part of industrial and commercial America. It’s cheap to purchase, remains durable for years, and can resist fire and heat damage.

Some often-discussed mesothelioma risk factors are still being researched. They include:

Asbestos can be found in many construction materials, such as spray-on insulation and roofing tiles. It’s also found around electrical wiring, switch boards and panels, automobile brakes, paint, floorboards, siding and more. This is why occupational exposure to asbestos is linked to the rise of mesothelioma cases.

Asbestos was a regular building component in the United States military. The substance is part of most, if not all, naval ships built between the 1930s and 1980s. The military’s use of asbestos is why many veterans develop mesothelioma.

Types of Asbestos

Asbestos falls into two mineral families: serpentine and amphibole. There is one type of serpentine asbestos and five types of amphibole asbestos.

Serpentine Asbestos vs. Amphibole Asbestos

Serpentine fibers are long, curly and layered. The only known type is chrysotile. According to the Penn Medicine website, “Chrysotile asbestos is the cause of most cases of mesothelioma.”

Amphibole fibers are short, straight and sharp, similar to a needle or pin. They’re structured in a chain-like formation. According to Penn Medicine, amphibole asbestos is easy to inhale.

According to an article by Mineral Direct, most hazardous fibers are shorter in length because they can travel easily through your body. This is why amphibole asbestos can be harmful. However, both types of asbestos can be dangerous.

Asbestos Subtypes

There are six different subtypes of asbestos used in products: tremolite, actinolite, anthophyllite, chrysotile, amosite and crocidolite. The two used most often are chrysotile and amosite. These asbestos subtypes can be found in construction materials and automobile parts.

Where Is Asbestos Found?

You can find asbestos in homes, schools, offices, automobiles and other vehicles and buildings. Despite the significant reduction in use, asbestos remains dangerous due to its presence in deteriorating buildings.

The United States imported around 100 metric tons in 2019. The amount rose — nearly doubled — in 2020. The following are home, automobile or office building components that may have asbestos:

Asbestos Found in Downtown Public Locations

Two reports revealed that asbestos can exist in downtown locations of major cities. In 2019, asbestos was found in a New York bus depot. According to the New York Daily News, there was a heavy amount of asbestos that put thousands of MTA employees in danger of exposure.

The depot is a storage location for the buses. Some vents at the depot pump air into each floor of the building. According to the report, most of the vents sending air into the first three floors “are lined with asbestos-laced cloth.” The fan room circulates air through the vents and into the rooms. The number of workers possibly exposed were:

• 700 bus operators
• 120 maintenance workers
• 50 dispatchers
• 100 office workers

The MTA also has internships for high school students.

Another instance was a pipe leak in downtown Boston that released asbestos dust into the air and on a road. In 2019, a steam pipe leak caused Boston city officials to close down several streets around Summer Street and Downtown Crossing.

Asbestos leaked through a manhole and caused dust to litter the street. A picture posted to the Boston Fire Department’s Twitter account shows a white substance covering the road and a parked car. It’s unknown how many residents were in the area at the time of the leak.

Mining and Importing Asbestos

Mining for asbestos in the United States started in the late 1800s. It continued the entirety of the 20th century. Mining occurred to meet high industrial demands for the mineral.

Asbestos mining involved an open-pit (an open area similar to a valley) method. When asbestos is first extracted, it looks like old wood. It is then turned into a fluffy fiber. The refined asbestos is added to other materials, like cement or insulation.

Mining of asbestos in the United States ended in 2002 when a chrysotile deposit in California closed. In 2018 the country brought in 750 metric tons:

From 2006-2014, the U.S. imported more than 8 million pounds of asbestos. Most of the asbestos came from Brazil. The port bringing in the largest amount of asbestos was New Orleans, Louisiana. The following ports in the United States are known for receiving large shipments of asbestos:

Where in the United States Was Asbestos Mined?

The most famous asbestos mine was the vermiculite mine in Libby, Montana. The mine included amphibole asbestos. It shut down in 1990 and is responsible for many mesothelioma cases.

The Agency for Toxic Substances and Disease Registry lists 27 processing sites for Libby’s vermiculite mine. One of them is Libby, and the other 26 locations are:

Asbestos was once mined in nearly half of the states in the country. The U.S. Department of Interior reported 27 former asbestos mines in North Carolina and 17 in Georgia. Other states are:

Who Faces the Highest Risk of Asbestos Exposure?

People who worked directly with asbestos materials have the highest risk of developing asbestos-related cancers. Most mesothelioma cases are due to occupational asbestos exposure. Construction workers (such as carpenters), insulation workers, electricians, pipefitters and others:

• Handled asbestos products directly
• Applied asbestos to building components
• Were exposed to asbestos when fixing or repairing a building

According to the Agency for Toxic Substances and Disease Registry, “In the United States, an estimated 27 million workers were exposed to aerosolized asbestos fibers between 1940 and 1979.”

Occupational exposure isn’t in the past, either. Workers are still subjected to asbestos when working on 20th century buildings. Occupational exposure occurs during:

• Repairs
• Renovations
• Asbestos removal
• Maintenance

Based on research from the American Thoracic Society, as of today, “1.3 million construction workers as well as workers in building and equipment maintenance” are exposed to asbestos.

Is Asbestos Banned in the United States?

The U.S. Environmental Protection Agency (EPA) officially banned the sale, use, and import of chrysotile asbestos on March 18, 2024. Chrysotile asbestos was reportedly the only of the six types still imported and used in the U.S., primarily for the chlor-alkali industry.

Chrysotile asbestos is the most common type of the mineral. It’s also the type most often causing mesothelioma cancer.

Chrysotile asbestos has been used for decades to strengthen construction materials, textiles and cement, along with gaskets, clutches and brake pads for automobiles. The EPA reports chrysotile asbestos is found in asbestos diaphragms, sheet gaskets, oilfield brake blocks, aftermarket automobile brakes and linings, vehicle friction products and other gaskets.

Prior to this ban, there were strict regulations in place, which limited the use of asbestos in the United States. Other types of asbestos are not formally banned but have strict regulations in place and have not been reported recently as an imported good.

History of Asbestos Ban Attempts

More than 60 countries had banned asbestos, but the U.S. wasn’t one of them. As of 2023, The Ban Asbestos Now Act was in both the House of Representatives and Senate for a significant period of time. The goal was to outlaw all commercial mining, production, and sale of asbestos within one year of passage. Activists were hopeful for its passing, but it remained just a bill with promise until the final passing of the chrysotile asbestos ban in 2024.

In 1989 the Environmental Protection Agency (EPA) attempted to ban asbestos. Unfortunately, the result was banning only new uses of the carcinogen. Uses of asbestos prior to 1989 remained legal.

The U.S. Consumer Product Safety Commision in the 1970s banned the use of asbestos in wallboard patching and gas fireplaces. Around this same time, asbestos was removed from electric hair dryers.

In the early 2000s, crayon manufacturers refined their recipes when asbestos was discovered in their crayons. During this timespan, the EPA also expressed concern about asbestos contamination in gardening products containing vermiculite. Recently, traces of asbestos have been found in talc cosmetic products (baby powder, makeup and blush).

In April 2019, the EPA established new regulations for asbestos. The agency must approve any company’s use on a case-by-case basis rather than listing specific uses that are permitted and those that are banned. These regulations still apply to all types aside from chrysotile asbestos, which is banned. Critics of the EPA’s new rules say the agency could be lenient, allowing for previously banned implementations of the substance.

How Asbestos Causes Mesothelioma

When fibers are stuck together and form a large piece of asbestos, they’re harmless. However, they’re flaky and sensitive. The slightest touch or breath from a person can loosen one or many of these fibers, which is how asbestos can cause cancer.

A single strand’s weightless composition allows wayward fibers to float in the air, and they are too small for people to detect without a microscope. Anyone near loose, airborne asbestos fibers can inhale or swallow them without even realizing.

The fibers can travel through the body and reach the lung cavity or the abdominal cavity. The lung cavity is protected by a thin layer of tissue called the pleura. The abdominal cavity includes a similar layer, called the peritoneum.

When asbestos fibers reach either of these two layers, it can aggravate mesothelial cells by lodging into the tissue lining with its sharp edges. This irritation causes the cells to change genetically, which leads to mutation and eventually the cancer known as mesothelioma.

If you have this disease, we can provide more information and evidence about how asbestos is the cause. Our free Complete Mesothelioma Guide book is full of data and statistics regarding asbestos, its use in the United States, and what you can do if you have mesothelioma.