Millions of preterm births and thousands of infant deaths linked to plastic chemicals worldwide

Prematurity is on the rise in the United States and other nations, experts say. (Credit: Jennifer Brückner/picture alliance/Getty Images via CNN Newsource)

Two chemicals used to make plastic more flexible are linked to nearly two million premature births and the deaths of 74,000 newborns worldwide in 2018, according to a new study.

A baby is considered premature when it is born before the 37th week of pregnancy. About 1 in 10 infants in the U.S. was born premature in 2024, according to the 2025 March of Dimes Report Card.

“Babies who survive may have breathing problems, feeding difficulties, cerebral palsy, developmental delay, vision problems, and hearing problems,” according to the U.S. Centres for Disease Control and Prevention.

The two chemicals in the study — Di-2-ethylhexylphthalate, or DEHP, and its cousin diisononyl phthalate, or DiNP — are part of a family of synthetic chemicals called phthalates.

Phthalates are known to interfere with the body’s mechanism for hormone production, known as the endocrine system, and are “linked with developmental, reproductive, brain, immune, and other problems,” according to the National Institute of Environmental Health Sciences. Even small hormonal disruptions can cause “significant developmental and biological effects,” the institute says.

“This is a dangerous class of chemicals,” said Dr. Leonardo Trasande, senior author of the new study and the Jim G. Hendrick, M.D., Professor of Pediatrics at NYU Langone’s Grossman School of Medicine in New York City.

“In the context of all the efforts that we’re taking to have more babies born in the United States, we should also make sure that babies are born healthy,” said Trasande, who is also a professor of population health and director of the Division of Environmental Pediatrics and the Centre for the Investigation of Environmental Hazards at NYU Langone Health.

“These data further support efforts to negotiate a plastic treaty that limits chemicals of concern commonly used in plastics,” he said.

The American Chemistry Council’s High Phthalates Panel told CNN in an email that the U.S. Environmental Protection Agency conducted a comprehensive risk evaluation of uses of DiNP under the Toxic Substances Control Act and concluded that it does not pose “unreasonable risk of injury to human health for consumers, the general population, or the environment.”

The council, which represents the U.S. chemical, plastics and chlorine industries, provided no comment on di-2-ethylhexylphthalate, or DEHP.

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‘Everywhere’ chemicals

Phthalates are often called “everywhere” chemicals because they are used in so many consumer products. The chemicals provide flexibility in children’s toys, art supplies, food storage containers, vinyl flooring, shower curtains, garden hoses, medical devices and more.

Phthalates also help lubricate substances and carry fragrances in personal care products, including deodorants; nail polishes; perfumes; hair gels, sprays or shampoos; soaps; and body lotions.

“These are additives that are also used in the cling-type plastic wrapping plastic that is commonly used in food packaging,” Trasande said.

Research has linked phthalates with reproductive problems such as genital malformations and undescended testes in baby boys and lower sperm counts and testosterone levels in adult males. Studies have also linked phthalates to childhood obesity, asthma, cardiovascular issues and cancer.

A 2021 study coauthored by Trasande found that phthalates may contribute to 91,000 to 107,000 premature deaths a year among people ages 55 to 64 in the United States. People with the highest levels of phthalates had a higher risk of death from any cause, but especially from heart disease.

How might these chemicals contribute to preterm births and infant deaths? Although much more research needs to be done, scientists have some ideas.

“One pathway is the disruption of placental function which has been documented to be affected by phthalates and other endocrine disrupting chemicals,” said Jane Muncke, managing director and chief scientific officer at the Food Packaging Forum, a nonprofit foundation based in Zurich, Switzerland, that focuses on science communication and research on plastics and other chemicals used in industry.

“Ironically, babies born preterm will be exposed to even more plastics, as neonatal wards rely on plastic tubing,” said Muncke, who was not involved with the latest study. “This is also a big, pressing reminder that innovation into safer materials, especially for use in health care, is urgent and should be a high priority for policymakers and entrepreneurs.”

The placenta, which attaches to the uterine wall, provides oxygen, nutrients and immune support to the developing fetus. Placental insufficiency, in which the organ fails to develop or function properly, is a leading cause of spontaneous preterm birth, experts say.

“Inflammation isn’t very good for placental adhesion and may facilitate ruptured membranes,” Trasande said. “Ruptured membranes, a lack of adhesion to the uterine wall and a loss of key nutrients to the fetus may trigger uterine contractions. There’s no singular pathway.”

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An entire class of chemicals

The new study, published Tuesday in the journal eClinicalMedicine, examined the effects of DEHP and DiNP across 200 countries and territories in 2018. Data was pulled from large national surveys in the Canada, Europe and the United States as well as estimates from earlier investigations in regions of the world that do not collect their own data.

Africa, the Middle East and South Asia carried the brunt of the premature health burden. Some of those areas have rapidly growing plastics industries and high levels of global plastic waste, the study said.

The investigation was not designed to establish that DEHP and DiNP directly or alone cause preterm birth, nor did it analyze other types of phthalates, the authors said.

That makes sense, said Dr. Donghai Liang, an associate professor of environmental health at Emory University’s Rollins School of Public Health in Atlanta.

“Specifically, DEHP has been one of the most widely studied phthalates in relation to preterm birth, so there is a stronger epidemiologic basis for modeling its contribution,” Liang, who wasn’t involved in the research, said in an email. “DiNP was included because it is a common replacement for DEHP and is increasingly relevant as industries shift away from older phthalates.

“That said, I would not interpret this as meaning only these two phthalates matter,” he said. “The broader concern is really about phthalates as a class and focusing on one or two at a time may underestimate the overall risk.”

Manufacturers often search for replacements to chemicals that science has linked to health harms and that are being regulated by federal and state governments. For example, in 2008, the U.S. banned DEHP in concentrations greater than 0.1 per cent in children’s toys and child-care articles, and two states — California and North Carolina — are working to ban DEHP in IV solution bags.

“We are playing a dangerous game of Whac-A-Mole with hazardous chemicals,” Trasande said. “We have a situation in which concerns come up about one chemical, and industry simply replaces it with a chemical analog that may have the same, if not worse, effects.”

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How to avoid phthalates

The good news is that phthalates have a short half-life and leave the body within a few days, experts said. Therefore, careful planning to avoid plastics can have a significant impact.

“For mothers and expecting families looking to minimize exposure, there are some reasonable and practical steps that can help,” Liang said. “These include choosing personal care products labeled ‘phthalate-free.’ Check ingredient lists for terms like diethyl phthalate (DEP), dibutyl phthalate (DBP), and benzyl butyl phthalate (BBzP).”

However, product labels do not always list chemicals in a consistent way. For example, in personal care products, phthalates are often included under broader terms like “fragrance” or “parfum,” Liang said.

“Phthalates are important additives to make fragrances stay fragrant,” Trasande said. “Another key tip: As heat encourages chemicals like phthalates to leach from the plastic, avoid microwaving or machine dishwashing plastic.”

Use proper ventilation to improve indoor air quality and do regular vacuuming, since phthalates can accumulate in household dust, Liang added.

“That said, it is important to emphasize that these exposures are widespread and often difficult to fully avoid,” he said. “Meaningful protection cannot rely solely on individual behavior. The most effective solutions are upstream, including stronger regulations, safer product formulations, better labeling, and improved environmental management and regulatory oversight.”

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