Asbestos exposure

Asbestos exposure occurs when an individual comes in contact with a naturally occurring fire-resistant mineral fiber, historically used in numerous, varied applications ranging from lamp wicks to brakes to roofing shingles, that consists of silica compounds. These compounds can irritate human tissue, which may result in disorders such as asbestosis as well as cancers of the lung, larynx, ovaries, or gastrointestinal system.

Causes and Symptoms

Asbestos is a naturally occurring mineral fiber whose fire-resistant properties have been known since antiquity. There are six different forms of asbestos. Some are more associated with illness and disease than others, particularly among workers in industries that use or encounter asbestos.

All shares a common characteristic: because asbestos consists of silica crystals, the fibers are inherently irritating to human tissue. On the surface of the skin, they can become embedded and lead to the formation of calluslike growths, termed “asbestos warts,” as the body attempts to encapsulate the irritating fibers.

Inhaled or ingested asbestos fibers are a more serious matter; though there is no definitive link between asbestos in drinking water and later illness, asbestos in airborne water particles, as in showers or humidified rooms, may be inhaled as well.

Asbestos exposure has been associated with cancers of the ovaries, larynx, stomach, liver, and other organs. But asbestosis and mesothelioma are the two most common asbestos-related health disorders.

Asbestosis, a lung disorder caused by fiber-related scarring of lung tissue, was one of the first disorders associated with asbestos exposure. It is now known that the fibers do not scar the directly; rather, they trigger the production of acid by the lung tissue as the body attempts to break down the silica crystals. Asbestosis is similar to disorders such as silicosis, “brown lung,” and “black lung” in that lung capacity is reduced as cumulative damage reduces the affected person’s ability to breathe.

Mesothelioma, a particularly invidious cancer, is also associated with asbestos exposure. With this form of cancer, the cells between the walls of the (the outer covering of the lungs that separates the lungs from the chest wall) or the (the sac containing the abdominal organs) form malignant growths.

Both asbestosis and mesothelioma may take many years to develop, with some affected people not developing mesothelioma until as many as forty years after the initial exposure. On the other hand, there have been cases of adolescents developing mesothelioma within only a few months of initial asbestos exposure.

Treatment and Therapy

Localized “asbestos warts” on the skin may be unattractive, but they are generally benign. The lung diseases associated with asbestos exposure, however, are progressive and ultimately fatal. In asbestosis, the scarred lung tissue becomes increasingly stiff, and the person becomes unable to take in sufficient oxygen.

Mesothelioma has a high rate, as it is rarely detected in its early stages. Symptoms such as shortness of breath are attributed to more common diseases such as asthma. As the cancer spreads, lung capacity is diminished, and the person eventually dies from the inability to take in sufficient oxygen, provided they have not already succumbed to other organs failing after the cancer metastasizes.

Perspective and Prospects

The ancient Romans, as well as other cultures throughout recorded history, mined asbestos for manufacturing fireproof mats and garments. Neolithic inhabitants of Scandinavia used asbestos in their pottery as well. During the nineteenth century, asbestos became a popular material for lamp wicks, as it could convey the lamp oil without being consumed by the flame itself. As industrialization progressed, asbestos became widely used in such applications as brake shoes for automobiles, oven linings in electric stoves, and building materials. Asbestos was impregnated into siding and for exterior walls and roofs, insulation for attics and walls, and ceiling and floor tiles. By the mid-twentieth century, asbestos had become ubiquitous in society, from the materials on which people walked to the roofs over their heads.

The dangerous nature of asbestos production has long been known. The Romans recognized that mining asbestos was effectively a death sentence, as enslaved people working in asbestos production quickly developed coughs and wasted away from lung diseases. As mining was generally a dusty and dangerous occupation, the special risks presented by asbestos were not well recognized, however. For centuries, many physicians assumed that all miners’ lung ailments were forms of consumption (tuberculosis), when in fact was an opportunistic infection that followed after a miner became weakened by disorders such as silicosis and asbestosis.

By the 1930s, researchers had established that asbestos presented especially high risks of causing lung diseases in miners, shipyard workers, and others who either manufactured or worked with materials incorporating asbestos, such as insulation. By the mid-twentieth century, it had become evident that extremely small amounts of asbestos exposure could lead to asbestos-related disorders. Miners’ spouses developed mesothelioma after being exposed to asbestos through doing laundry, for example, while children became victims through exposure to their parents’ work clothes in the home.

Efforts to ban the use of asbestos in the US began in the late twentieth century but met with stiff industry opposition. Nonetheless, by the late 1970s, the US Environmental Protection Agency (EPA) had banned most friable asbestos products and several major kinds of acoustical materials, spray-applied insulation, and fireproofing that contained asbestos. In 1989, the EPA banned most all asbestos applications and mandated an eight-year phaseout of asbestos in consumer products. However, in 1991, a federal court overturned this ruling and limited the ban.

More than three decades later, in 2023, the EPA required more detailed reporting on the types of legacy asbestos still used in manufacturing. The following year, it also banned use of the most common form, chrysotile asbestos, with phaseouts for the automotive parts and chlor-alkali industries, where it was still in use for brakes and chlorine production for water treatment. By then, asbestos exposure was responsible for an estimated forty thousand deaths a year in the US alone.

Despite those efforts, the widespread historical use of asbestos fibers in multiple applications means that exposure remains a concern in the twenty-first century. Although asbestos is no longer as widely used in industry, reducing the prevalence of workplace exposures, people can still risk asbestos exposure when engaging in home improvement projects as they rip out old flooring or replace ceiling tile, for example, or when asbestos-containing objects or structures are damaged.

Bibliography

“Asbestos.” MedlinePlus, 6 Feb. 2017, medlineplus.gov/asbestos.html. Accessed 24 Feb. 2017.

“Asbestos and Cancer Risk.” American Cancer Society, 3 Oct. 2023, www.cancer.org/cancer/cancer-causes/asbestos.html. Accessed 22 Mar. 2024.

“Asbestos in the Natural Environment: How Safe Are We?” UN Environment Programme, 21 June 2019, www.unep.org/news-and-stories/story/asbestos-natural-environment-how-safe-are-we. Accessed 22 Mar. 2024.

Bardelli, F., et al. “Closing the Knowledge Gap on the Composition of the Asbestos Bodies.” Environmental Geochemistry and Health, 14 Apr. 2023, link.springer.com/article/10.1007/s10653-023-01557-0. Accessed 1 Aug. 2023.

Bowker, Michael. Fatal Deception: The Terrifying True Story of How Asbestos Is Killing America. Touchstone, 2003.

“EPA Takes Another Step to Protect the Public from Asbestos Exposure by Finalizing Rule to Require Comprehensive Reporting.” United States Environmental Protection Agency, 6 July 2023, www.epa.gov/newsreleases/epa-takes-another-step-protect-public-asbestos-exposure-finalizing-rule-require. Accessed 1 Aug. 2023.

Frank, A. L. “Global Problems from Exposure to Asbestos.” Environmental Health Perspectives Supplements, vol. 101, no. 3, 1993, pp. 165–68.

Gorvett, Zaria. “Asbestos: The Strange Past of the ‘Magic Mineral.’” BBC Future, British Broadcasting Corporation, 7 Feb. 2024, www.bbc.com/future/article/20240207-asbestos-the-strange-past-of-the-magic-mineral. Accessed 22 Mar. 2024.

Hernandez, Joe. “The U.S. Bans Most Common Form of Asbestos, after Decades of Pushback from Industry.” NPR, 18 Mar. 2024, www.npr.org/2024/03/18/1239299448/the-u-s-bans-most-common-form-of-asbestos-after-decades-of-pushback-from-industr. Accessed 22 Mar. 2024.

Puko, Timothy. “EPA Struggles to Ban Asbestos, Other Chemicals Years after Congress Granted New Powers.” The Washington Post, 19 Feb. 2023, www.washingtonpost.com/climate-environment/2023/02/19/epa-struggles-ban-asbestos-other-chemicals-years-after-congress-granted-new-powers. Accessed 1 Aug. 2023.

National Heart, Lung, and Blood Institute. “What Are Interstitial Lung Diseases?” National Institutes of Health, 24 Mar. 2022, www.nhlbi.nih.gov/health/health-topics/topics/asb. Accessed 22 Mar. 2024.

Roggli, Victor L., et al. Pathology of Asbestos-Associated Diseases. 2nd ed., Springer, 2004.

Tucker, Danielle Torrent. “U.S. Asbestos Sites Made Risky by Some Remediation Strategies.” Stanford Doerr School of Sustainability, Stanford University, 23 Apr. 2021, sustainability.stanford.edu/news/us-asbestos-sites-made-risky-some-remediation-strategies. Accessed 22 Mar. 2024.