If there’s one thing that’s everywhere, it’s plastic. Its ubiquity — in everything from food containers to flooring and lotion bottles — may contribute to tens of thousands of premature births each year, a new study finds.

The issue is phthalates, the synthetic chemicals in plastic, per the research, which was published this week in Lancet Planetary Health. Phthalates are known to be hormone disruptors.

CNN notes that phthalates are sometimes referred to as “everywhere chemicals” because they are used in so many things.

The chemicals could be tied to more than 56,000 preterm births in the U.S. in a year, leading to lifetime medical costs that could range from $1.6 billion to $8.1 billion over those children’s lifetimes, according to a news release from NYU Grossman School of Medicine, which led the study.

The release said phthalates “have been shown to interfere with the function of certain hormones, signaling compounds that circulate in the blood and guide much of the body’s processes. Exposure to these toxins, which is believed to occur as consumer products break down and are ingested, has been linked to obesity, cancer and fertility issues, among many other health concerns.”

The study of phthalate exposure in more than 5,000 U.S. moms found an association with greater risk of low birth weight and prematurity, two factors already known to at least slightly increase the risk of infant death, lower academic performance, and possibly promote heart disease and diabetes.

The Centers for Disease Control and Prevention reports that phthalates are a group of chemicals used to improve plastic durability, and are found in everything from vinyl flooring and personal-care products to lubricating oils. They make plastic flexible and shiny, too.

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“Our findings uncover the tremendous medical and financial burden of preterm births we believe are connected to phthalates, adding to the vast body of evidence that these chemicals present a serious danger to human health,” said study lead author Dr. Leonardo Trasande, professor of pediatrics at NYU Langone Health, in a prepared statement. “There is a clear opportunity here to lessen these risks by either using safer plastic materials or by reducing the use of plastic altogether whenever possible.”

Looking for links to prematurity

The prospective analysis used data from the National Institutes of Health’s Influences on Child Health Outcomes Program from 1998 to 2022 to see how 20 phthalate metabolites were associated with gestational age (the length of time from conception to birth), birth weight, birth length and other factors. Researchers also calculated the cost of adverse birth outcomes. The dataset included information on access to food, the impact of social inequality on toxin exposures and more. They were able to control for demographic factors and concentrate on the phthalates.

Three times during the pregnancy, researchers measured levels of 20 different metabolites in urine. Metabolites are what substances break down into. Then they checked their findings on metabolites against preterm births. And finally, they estimated the costs of intensive care unit stays and other medical bills resulting from preterm birth, as well as time lost from work over a lifetime.

They found that phthalate exposure was associated with lower gestational age “in a large and diverse sample” that was generally nationally representative, they wrote, noting particular concern because some of the chemicals are being used in food packaging.

When the researchers homed in on certain phthalates, they found that the 10% of women with the greater exposure to di-2-ethylhexyl phthalate (DEHP) had a 50% increased risk of giving birth prematurely, compared to those with the lowest 10% in terms of levels. And risk doubled for women exposed to the highest quantities of three other phthalates that are “alternatives” to DEHP: di-isodecyl phthalate (DIDP), di-n-octyl phthalate (DnOP), and diisononyl phthalate (DiNP).

“These results demonstrate the need to regulate phthalates as a class rather than trying to address them one at a time,” Trasande said. “Otherwise, investigators are likely going to find the same study results in another few years about the next group of chemicals used as replacements.”

A fix that might not work

USA Today notes that chemical companies have been replacing chemicals known to pose risk, like DEHP, but that won’t help if the study’s correct that the replacements are just as problematic.

Per the article, “It’s important to note that the new study is observational and doesn’t necessarily prove causal effect of plastics on preterm birth. However, scientists unaffiliated with the study said it builds on established evidence, and it yields new findings about chemical substitutes they said avert regulations.”

Trasande said people should skip packaged goods when possible. And food should be stored in glass or stainless steel, he added.