The U.S. Environmental Protection Agency has announced a final rule to prohibit the ongoing use of a certain type of asbestos that is currently used in the chlor-alkali industry in the production of chlorine.

According to some critics of the ruling, the ban could have serious consequences for the supply and price of chlorine.

The final rule was announced on March 18 and provides from five to 12 years to phase out the use of asbestos in the production of chlorine, a critical use of which is disinfecting water.

At present, asbestos diaphragms are used to make one third of the chlorine that is produced in the United States. The path to arriving at the EPA’s final rule has been controversial. Industry representatives have argued that banning asbestos will result in significant disruptions of the chlorine supply.

There are three major chloralkali companies — Occidental Chemical Corporation (OxyChem), Olin Corporation, and Westlake Chemical Corporation — that continue to use asbestos diaphragms in the production of chlorine. Only one of these companies, Oxychem, continues to import asbestos from Brazil and China. Westlake and Olin stopped importing asbestos in 2016 and 2021 but continue to use it from their stockpiles.

In its original 2022 proposal, the EPA suggested a 2-year phaseout period for banning asbestos diaphragms. In response, the American Chemistry Council (ACC), the Chlorine Institute, Oxychem, Westlake, and others stated that a 15-year phase-out was needed to convert to non-asbestos diaphragms or membrane technology.

In comments solicited by the EPA, the ACC, which represents OxyChem, stated that a rapid phaseout of asbestos would result in “critical” shortages of chlorine for water treatment and “substantial” price increases that would “harm countless Americans who benefit from the disinfection and industrial uses of chlorine.”

But Olin, the largest of the chloralkali companies, supports the EPA’s rule and has stated that a 2-to-7-year phase-out is reasonable and that the ACC does not represent overall chloralkali industry interests.

Scott Sutton, CEO of Olin, said: “Olin supports an immediate ban on asbestos imports into the United States, which will protect those who may be exposed to this material along the supply chain. Olin will also purge the existing asbestos from our assets within seven years, which is necessary to carry out the extensive work of modifying thousands of individual diaphragm components with new material and to prevent any shortages of critical chlorine in the meantime. Any suggestion by other industry groups or companies that this timeframe is unachievable is simply untrue — Olin has the largest asbestos diaphragm capacity of any producer in the world, and we are confident that this timeline is achievable.”

Compared to the EPA’s initial plan, which suggested a 2-year asbestos phase-out, the final rule is a compromise, outlining a 5-year transition for six of the eight chloralkali plants that are still using asbestos diaphragms in the United States.

The remaining have up to 12 years to convert the last of their facilities to non-asbestos technologies.

Some critics of the asbestos rule have said it’s an unnecessary and costly measure.

In a comment posted to the EPA’s initial proposal, the Dow Chemical Company wrote, “Asbestos diaphragms are fully enclosed, therefore there is no exposure, and as such, no risk for humans and the environment.”

But workers at a now-shuttered New York OxyChem plant told a different story. More than a dozen former workers of the facility reported dangerous and unacceptable working conditions that went unchecked by plant management and government overseers for years.

Workers said that they implored the plant’s managers to address the conditions, but the dangers remained until the plant closed.

An article in ProPublica described the conditions: “Asbestos dust hung in the air, collected on the beams and light fixtures, and built up until it was inches thick. Workers tramped in and out of it all day, often without protective suits or masks, and carried it around on their coveralls and boots.”

Asbestos is a known cancercausing substance with no known safe exposure level. By one estimate, more than 40,000 Americans die each year from asbestos-caused cancers, including lung cancer, mesothelioma, and cancers of the larynx and ovaries. Formerly used in insulation and in fire prevention, its use began to be banned in the U.S. in the 1970s to prevent human exposure. The latest rule prohibits the use of chrysotile asbestos, the only known form of asbestos currently used in or imported to the United States.

According to the EPA, “The action marks a major milestone for chemical safety after more than three decades of inadequate protections.”