“Fast fashion” is an affordable way for parents to keep up with their kids’ growth spurts, but these cheaper duds might come with real health risks, a new study says.

The fabric in some fast-fashion shirts contains high levels of lead, researchers reported Monday at the spring meeting of the American Chemical Society in Atlanta.

Even briefly chewing these fabrics — as young children will do — can expose them to dangerous levels of lead, researchers said.

“Not only are children the most vulnerable to the effects of lead, but they’re also the population that is going to be putting their clothes in their mouths,” researcher Cristina Avello said in a news release. She’s a pre-medical student at Marian University in Indianapolis.

No level of lead exposure is safe for children, according to the U.S. Centers for Disease Control and Prevention (CDC). It can damage the brain and nervous system, leading to delayed development.

Previous studies have found high levels of lead in the metal parts of some children’s clothes, like zippers, buttons and snaps, researchers said.

But lead is also used in some textiles, as an inexpensive way to help dyes stick to materials and produce bright, long-lasting color, researchers said.

For the new study, researchers tested 11 shirts from four different retailers, including fast-fashion and discount companies. The shirts spanned the rainbow in red, pink, orange, yellow, gray and blue colors.

“The shirts we tested were all over the allowed limit for lead of 100 parts per million,” researcher Priscila Espinoza, another pre-medical student at Marian University, said in a news release.

No matter the brand, brightly colored textiles like red and yellow tended to have higher levels of lead than less flashy colors, researchers found.

To follow up, researchers simulated stomach digestion to calculate whether children could absorb lead from these fabrics.

The results suggest that exposure from mouthing behavior — sucking or chewing on fabric — would exceed the daily lead ingestion limit for children set by the U.S. Food and Drug Administration (FDA).

Frequent chewing over time could increase a child’s blood levels to the point where they need medical attention, researchers concluded.

The team plans to study more shirts and test how laundering affects the lead levels of clothing. They are concerned that washing lead-contaminated coating might spread the toxic metal to other garments or the wastewater discharged by washing machines.

Natural alternatives are available to help fix dyes to fabrics and keep them vibrant, “but if you want to change the clothing industry’s technology, that will cost a lot of money,” said senior researcher Kamila Deavers, an assistant professor of chemistry at Marian University.

Findings presented at scientific meetings should be considered preliminary until published in a peer-reviewed journal.