The Environmental Protection Agency (EPA) plans to regulate how phthalate chemicals are used in work settings, a decision made after the agency completed its risk evaluation under the Toxic Substances Control Act, EPA administrator Lee Zeldin said in a Dec. 31 post on X.

Phthalates, used mainly as plasticizers in PVC products, are utilized in many industrial and consumer products.

According to a Make American Healthy Again (MAHA) commission report, research has shown that certain phthalates can “trigger hormone dysregulation and reproductive and developmental problems for babies in-utero and infants.”

In his post, Zeldin said the EPA conducted “the most comprehensive” assessment of phthalates. “We are now announcing that, following gold standard science, promoting radical transparency of the research and data, and to Make America Healthy Again, we will regulate dozens of phthalate chemical uses after finding unreasonable risks to workers and the environment.”

The decision was made after evaluating available information on phthalates using the “most rigorous” scientific methods, including cutting-edge cumulative exposure analysis and independent expert peer reviews, Zeldin said.

In a Dec. 31 statement, the EPA announced its intent to regulate dozens of uses of five phthalate chemicals—butyl benzyl phthalate (BBP), dibutyl phthalate (DBP), dicyclohexyl phthalate (DCHP), diethylhexyl phthalate (DEHP), and diisobutyl phthalate (DIBP).

EPA said it was “seriously concerned” about health abnormalities that phthalates can potentially cause, including endocrine disruption and hormone deficiencies.

However, these health impacts “do not occur at all exposure levels,” it said. “The key factor in determining risk is whether people are exposed to amounts above levels that could cause health problems.”

For BBP, which is used in adhesives, floor coverings, and rubber products, the EPA identified that two types of uses of the chemical pose risks to workers while seven use cases pose environmental risks. For DEHP, used in paints, industrial polishes, and textiles, 10 types of uses were found to pose unreasonable risk to employees, and 20 uses were deemed to present risks to the environment. Similar assessments were made for DBP, DCHP, and DIBP.

The EPA said it will now develop rules to eliminate the identified risks.

“The agency will conduct extensive consultation with workers, businesses, labor groups, and communities to develop targeted, practical protections that ensure worker safety and environmental protection,” it said.

“Personal protective equipment, engineering controls, and alternative approaches will be carefully evaluated to create effective, implementable solutions that protect those most at risk.”

When determining whether a chemical poses unreasonable risks, the EPA said it takes into consideration factors such as health impacts, who gets exposed, and the severity and type of harm the chemicals can cause.

In another Dec. 31 statement, the EPA announced its intent to regulate almost a dozen uses of 1,3-butadiene—a colorless gas used to manufacture products such as car tires, paints, automotive care products, and adhesives and sealants.

The EPA said its review found potential unreasonable risks to workers who breathe in this chemical at their jobs in 11 industrial settings. However, no such risks were identified for the environment, customers, or the people living near facilities using the chemical.

Regular products only contain tiny amounts of 1,3-butadiene, typically less than 0.001 percent, which the EPA deemed to be safe.

However, “unreasonable risks are found in industrial settings where workers could be exposed to much higher levels that could lead to health risks which may include reduced birthweight pregnancies, anemia, leukemia, and bladder cancer.”

“The final rules will give companies clear regulatory certainty while providing workers with necessary protections,” the EPA said. “Our safeguards will be tough and practical. We will ensure the protections we put in place are workable, taking additional action if new science emerges or conditions change.”

According to the agency, the review process for the chemical took six years, with the EPA assessing around 20,000 scientific studies for 30 different use cases.