Written By: Camryn Keeble

Asbestos Exposure in Chlor-Alkali Plants

The chlor-alkali industry is responsible for 80% of the world’s chlorine production. The chemicals are used in various manufacturing processes and require asbestos for their own production. However, asbestos is a cancer-causing mineral, and exposure in chlor-alkali plants can be dangerous for workers. The ban of chrysotile asbestos should eliminate the use of asbestos in this industry in a few years.

Retired LCDR Carl Jewett

Reviewed By

Retired LCDR Carl Jewett

VA-Accredited Claims Agent

Retired LCDR Carl Jewett

Reviewed By

Retired LCDR Carl Jewett

VA-Accredited Claims Agent


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Important Facts About Asbestos Exposure in Chlor-Alkali Plants

  • Chlor-alkali refers to chemicals manufactured through electrolysis, such as chlorine gas and caustic soda (sodium hydroxide). The chemicals are used in many basic applications, including bleach, detergents, paper, textiles and more.
  • Asbestos is in thick metal screens inside the chlor-alkali electrolysis diaphragms. The insulation of asbestos helps the diaphragm deal with the stress from high electric currents and keep the chemicals separated.
  • Any level of exposure to asbestos is dangerous and can result in serious illnesses, such as lung cancer, asbestosis (lung tissue scarring) or mesothelioma cancer.
  • There are still several active chlor-alkali plants in the U.S. using asbestos, despite the Environmental Protection Agency (EPA) banning the substance. These plants have up to five years to transition to an alternative for making diaphragms.

What is Chlor-Alkali?

Chlor-alkali is a chemical manufactured through electrolysis. In the chlor-alkali process, salt brine (a mixture of sodium chloride and water) is dissolved in water and then fed into an electrolytic cell for the production of chlorine gas and caustic soda (sodium hydroxide).

The cells are powered by electricity that splits the sodium chloride (salt) into its two primary components: chlorine and caustic soda. Chlorine gas is used to manufacture bleach and other chemical products. Caustic soda is an important chemical in making paper, soaps and detergents, textiles, and many other products.

Chlor-alkali chemicals are components of a variety of everyday manufacturing processes, from water purification and fertilizers to detergents and pharmaceuticals. In 1987 alone, there were 35 million tons of chlorine produced through the chlor-alkali industry.

Asbestos Use in Chlor-Alkali Plants

Contrary to popular belief, asbestos was not banned until 2024 in the United States, despite more than 60 countries around the world banning the cancer-causing mineral sooner. The EPA banned chrysotile asbestos, which is the type used for chlor-alkali diaphragms. Chlor-alkali plants have five years to transition away from using chrysotile asbestos.

The United States EPA has implemented strict regulations limiting or preventing the use of the other five types of asbestos in most industries.

Asbestos Risks in Chlorine Production

The chlor-alkali industry has been the main source of chlorine production since the 20th century. Chlor-alkali plants are responsible for the chemical processes required to make chlorine, hydrogen, and sodium hydroxide (caustic) solution. These chemicals are often used in making paper, soaps and detergents, textiles, and many other products.

The manufacturing of chlor-alkali involves complex scientific processes, such as electrolysis, a technique using direct electric currents to initiate a chemical reaction. The electric currents in electrolysis are generated by a cathode and anode, which convert salt water into chlorine and sodium hydroxide solutions and are separated by an asbestos diaphragm.

Asbestos was incorporated into thick metal screens used in the chlor-alkali electrolysis diaphragms for its durability and resistance to heat. The insulation properties of asbestos help the diaphragm sustain the impact of the electric currents and keep the explosive chemicals separated.

Asbestos risks in chlorine production come from the use and maintenance of chlor-alkali equipment, especially the asbestos screens in the diaphragms. They required routine replacement, which often led to dispersed asbestos fibers throughout the work environment. There are reports of asbestos dust blankets covering certain areas of chlor-alkali plants.

Due to the use of asbestos in chlor-alkali plants, workers are at risk of occupational asbestos exposure.

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Asbestos Risks for Chlor-alkali Plant Workers

There is no safe level of asbestos exposure. Anyone working directly with the substance or near it is at risk of an asbestos-related disease. The chlor-alkali industry is no exception.

Large chlor-alkali companies claimed to implement extreme safety protocols for employees who may be working near asbestos, leaving almost no possibility of exposure. However, there is evidence of current and former chlorine plant workers developing serious health conditions related to asbestos exposure, such as lung cancer, asbestosis, and mesothelioma, a very rare cancer.

Asbestos Exposure and Mesothelioma

The only cause of mesothelioma is asbestos exposure. When asbestos is disturbed, the microscopic, needle-like fibers break apart and enter the air. Anyone in the area is at risk of inhaling or swallowing the invisible asbestos particles. 

If asbestos fibers are inhaled, they can enter the thin linings of the lungs, called the pleura. Due to the sharpness of asbestos, the fibers can stick to the pleura. There are mesothelial cells within the pleura, which can be mutated into cancerous mesothelioma tumors by asbestos fibers. This causes pleural mesothelioma

Swallowing asbestos fibers can cause the tiny particles to enter the lining of the abdomen, called the peritoneum. The asbestos fibers can become lodged in the peritoneum, causing irritation and cell mutation for the healthy mesothelial cells within the lining. Mutated mesothelial cells in the abdomen become malignant mesothelioma tumors, which results in a peritoneal mesothelioma diagnosis.  

There are approximately 2,500 new cases of mesothelioma each year in the United States. The rarity of this cancer is likely due to the long latency period, which is the amount of time between asbestos exposure and diagnosis. It can often last multiple decades. This prevents most people from seeking medical help as they likely do not know they are sick. 

Symptoms of mesothelioma may also appear vague and mimic other common health conditions, which makes for a challenging diagnosis. When diagnosing mesothelioma, specialists will often use an approach known as the “differential diagnosis,” which means they compile a list of possible causes and diseases based on the symptoms to determine the diagnostic testing needed. 

Treatment for mesothelioma often involves surgery, chemotherapy or immunotherapy. MesotheliomaGuide has a registered nurse on staff to help connect you with top mesothelioma specialists and cancer centers to find you the best treatment possible. If you currently or formerly worked in a chlor-alkali plant and have been diagnosed with mesothelioma, connect with our patient advocate, Karen Ritter. She can help you discover your options for medical care or legal support. 

Active Chlor-Alkali Plants Still Using Asbestos

Chlor-alkali plants are the main consumers of asbestos in the United States. According to the Chlorine Institute, there are 44 active chlor-alkali plants in the United States. However, according to the EPA, only eight use asbestos diaphragms in their production process.

Plants still using asbestos diaphragms are owned by four companies: Occidental Chemical Corporation (OxyChem), Olin Corporation, SABIC, and Westlake Chemical Corporation. 

In 2021, the U.S. imported 100 metric tons of asbestos, which is a drop from the 300 metric tons imported in 2020. However, the U.S. imported 114 metric tons in just the first three months of 2022. By the end of 2022, the chlor-alkali industry played a significant role in the import of nearly 400 metric tons.

The chlor-alkali market was valued at $76.21 billion in 2022, even with chlorine production declining approximately 10% (1.2 million tons) in the United States in 2021. This decline is directly related to the closure of manufacturing facilities, such as the Niagara Falls OxyChem plant and three Olin Corporation plants.

OxyChem’s Asbestos-Covered Chlor-Alkali Plant

A group of men who used to work at OxyChem’s chlor-alkali plant in Niagara Falls, New York, shared their experience with ProPublica in 2022.

The group describes their daily working conditions, stating that asbestos dust – sometimes inches thick – could be seen in every corner of the plant. Workers reportedly were not provided any type of asbestos protective equipment and were expected to continue working through the hazardous conditions.

OxyChem’s plant workers inhaled and ingested asbestos dust all day long and carried the cancerous substance around on their overalls and boots. This is called occupational asbestos exposure. They likely brought the toxic dust home to their families as they were greeted at the front door after a long day’s work, or washed their work uniform with the rest of the family’s laundry, leading to secondary asbestos exposure for their loved ones at home. 

Workers Urged Supervisors to Improve Working Conditions

Men like Henry S., an OxyChem chlor-alkali plant worker for nearly three decades, told ProPublica that they knew the health risks associated with asbestos and knew that their working conditions should not be acceptable.

Henry, along with his coworkers, reportedly urged their superiors to address the unsafe asbestos working conditions, but ProPublica reported that nothing changed. The asbestos dust blanketed OxyChem’s plant until the day it shut down in late 2021.

They continued to work amid the asbestos dust, trying their best to provide for their families and not inhale or ingest the dangerous fibers. Henry knew how harmful asbestos could be, but he began to believe it had probably already entered his body.

Workers assumed the company they worked for and regulatory agencies would protect them from asbestos as they did for most other industries. The supervisors, the OxyChem executives and government officials failed them by ignoring the unacceptable working conditions.

Chlor-Alkali Industry No Longer Opposes Asbestos Ban

In 2022, almost 30 years after the official halt in asbestos use, the EPA proposed a ban on chrysotile asbestos, the last type of asbestos still imported to the United States. The EPA officially enacted the ban in March of 2024.

However, the chlor-alkali industry has loudly opposed this ban, claiming the substance is a key element in chlorine production and banning it would disrupt the industry tremendously.

As recently as April 2022, the CEO of Olin Corp., a major chlor-alkali company, stated “acceptable asbestos replacement alternatives do not exist.” However, a year later, the CEO changed his stance, and now the company supports a complete ban on the substance.

Olin Corp.’s CEO wrote a letter to the EPA stating the corporation would support the total ban on asbestos if its companies were given seven years to phase out asbestos materials currently in use. The EPA is allowing up to five years for the plants to find an alternate way to produce diaphragms.

Our patient advocates are available to answer any questions regarding your asbestos exposure and its effects on your health. Contact Carl Jewett, our VA-Accreditted Claims Agent or Karen Ritter, our registered nurse. Both have helped many mesothelioma victims get answers to their questions. Email either of our patient advocates — Karen Ritter, RN (karen@mesotheliomaguide.com) or Carl Jewett (cjewett@mesotheliomaguide.com) — to get more information.

Sources & Author

  1. Global Chlor Alkali Market to 2028: Increasing Chlorine Production Bolsters Growth. GloablNewsire. Retrieved from: https://www.globenewswire.com/news-release/2023/07/07/2700978/0/en/Global-Chlor-Alkali-Market-to-2028-Increasing-Chlorine-Production-Bolsters-Growth.html. Accessed: 07/07/2023.
  2. Status of Chlorine Product Availability and Pricing. United States Environmental Protection Agency. Retrieved from: https://www.epa.gov/waterutilityresponse/status-chlorine-product-availability-and-pricing. Accessed: 07/07/2023.
  3. Major Chemical Company Changes Tune on Asbestos, No Longer Opposes EPA Ban. ProPublica. Retrieved from: https://www.propublica.org/article/asbestos-olin-chemicals-cancer-epa-chlorine. Accessed: 07/07/2023.
  4. Chlor-alkali products make everyday life safer, healthier and more convenient. Oxy. Retrieved from: https://www.oxy.com/operations/essential-chemistry/chlor-alkali/. Accessed: 11/16/2022.
  5. They inhaled asbestos for decades on the job. Now, workers break their silence. Npr. Retrieved from: https://www.npr.org/sections/health-shots/2022/10/20/1129999511/asbestos-ban-us-workers-cancer-risk. Accessed: 11/02/22.
  6. Lawsuits: A Factory Blew Asbestos Into a Neighborhood; Decades Later, Residents Are Getting Sick and Dying. ProPublica. Retrieved from: https://www.propublica.org/article/lawsuits-say-oxychem-released-asbestos-north-tonawanda. Accessed: 11/08/2022.
  7. Chlor-alkali process. Britannica. Retrieved from: https://www.britannica.com/technology/chlor-alkali-process. Accessed: 11/03/22.
  8. ACC Urges EPA to Reconsider its Flawed Chlor-alkali Proposal. American Chemical Counsel. Retrieved from: https://www.americanchemistry.com/chemistry-in-america/news-trends/press-release/2022/acc-urges-epa-to-reconsider-its-flawed-chlor-alkali-proposal#:~:text=Chrysolite%20asbestos%20is%20used%20by,89%25%20of%20crop%20protection%20chemicals. Accessed: 11/04/22.
  9. ADAO Chlor-Alkali Industry Report. Asbestos Disease Awareness Organization. Retrieved from: chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://www.asbestosdiseaseawareness.org/wp-content/uploads/2019/08/ADAO-ChlorAlkali-Industry-Report.pdf. Accessed: 11/07/22.
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About the Writer, Camryn Keeble

Camryn Keeble is the senior content writer and editor for Mesothelioma Guide. She creates informative content to educate mesothelioma patients and their loved ones on news, treatments and more. She also works diligently to raise awareness of the dangers of asbestos exposure and the effects of mesothelioma.