The Center for Environmental Health says lab tests show Disney, Marvel, and Nickolodeon character-themed children’s chairs contain chemicals linked to major health problems.

Many common children’s chairs sold at major retailers across the U.S. and Canada contain flame-retardant chemicals linked to cancer, hormone disruption, and infertility, according to a report released Wednesday from the Center for Environmental Health (CEH).

Caroline Cox, CEH’s research director and a co-author of the report “Playing on Poisons: Harmful Flame Retardants in Children’s Furniture,” said the flame retardants—applied to the polyurethane foam in the chairs’ cushions—aren’t relevant to the way fires ignite because the fabric covers don’t have the same fire protection.

“That’s why we figure there’s no fire safety benefit to treating the foam,” she told Healthline. “If there’s no fire safety benefit and these chemicals are toxic, it doesn’t look like there’s much benefit to using them.”

Learn More About Common Household Toxins »

Researchers purchased 42 items of children’s furniture in 13 different states and parts of Canada. The furniture can be purchased at Babies “R” Us, Toys “R” Us, Walmart, Kmart, Target, buybuy BABY, and other stores.

The furniture was then sent to the laboratory of Heather Stapleton, an environmental chemistry professor at Duke University. Stapleton’s testing found four flame retardant chemicals in 38 of the 42 samples. The chemicals found include Firemaster 550, TCPP, TDCPP, and butylated triphenyl phosphate. Ninety percent of the samples purchased at Toys “R” Us contained one or more of these chemicals.

These flame retardants have been linked to numerous health concerns, including disrupting the body’s hormone functioning, genetic damage, reproductive harm, and cancer.

Researchers say children are especially susceptible to the effects of these chemicals because of their developing minds and bodies, as well as how they interact with their surroundings, namely crawling and putting things in their mouths.

Researchers at the University of California, Berkeley’s Center for Children’s Environmental Research recently found that children, on average, have more than three times the levels of flame retardants in their bodies as their mothers.

The same research facility discovered that exposure to flame retardant chemicals is linked with poorer attention, decreased fine motor coordination, and lower IQ in school-aged children.

Read On: Flame Retardants Affect Children’s IQ, Firefighter’s Safety »

The chairs are often appealing to parents because they’re inexpensive and feature a number of children’s favorite characters, including Dora the Explorer, Spider-Man, and characters from Disney and Sesame Street.

Cox said there are other options that may be safer for children because they don’t contain flame retardant chemicals. These include furniture that are made of wood, polyester, canvas, or wicker.

“If you want to get your kid a chair, there are options that don’t have polyurethane foam in it. The foam is what has the chemicals in them,” she said. “If your holiday shopping list includes a small child’s chair, there are options out there.”

The CEH has an open letter on their website calling for Toys “R” Us to end the sale of products containing these flame retardants.

Representatives of Toys “R” Us could not be reached for comment.

Want to Clear the Air? Try These Air-Purifying Plants »