For decades, many of the foam products children touch and use every day – from changing pads and nursing pillows to play mats and mattresses – contained toxic fire retardant chemicals.

But recent changes in fire standards have made it possible for makers of children’s goods to manufacture these products without the chemical additives. There’s just one notable exception: car seats.

Federal law requires children’s car seats to be fire-resistant and to comply with the federal motor vehicle flammability standard FMVSS 302, set by the National Highway Traffic Safety Administration in 1991.

This regulation requires car seats to meet the same flammability standards as the rest of the car interior. To accomplish this, manufacturers add fire retardants chemicals to the polyurethane foam that pads the seats.

The Michigan-based Ecology Center tests car seats every year for these chemicals. Last year, every single seat the center tested contained some amount of fire retardants. Fully 73 percent contained halogenated fire retardants, which use chlorine or bromine and are especially toxic. Read more about the study.

The Ecology Center ranked Britax and Clek as the car seats that exposed children to the lowest concentrations of chemicals. Both companies are implementing policies to reduce hazardous fire retardant use.

Graco car seats ranked worst for chemical exposure, according to the Ecology Center. Click here to learn more about specific car seat brands.

Environmental health advocates are urging the National Highway Transportation Safety Administration to change its flammability standards either to exempt car seats from current regulations or permit the use of less toxic methods of protecting children from car fires.

The standard – which lawmakers created to prevent car fires, particularly those caused by cigarettes or matches – is increasingly outdated. Fewer Americans smoke in their cars. And a car seat is a very unlikely place for a fire to originate.

As parents demand safer car seats for their children, some companies are struggling to keep up. Popular car seat maker Orbit Baby has advertised its products as free of TDCPP, a fire retardant chemical on California’s Proposition 65 list of chemicals known to cause cancer, birth defects or reproductive harm. But tests show that the product did contain these chemicals. What’s more, the company had settled out of court for violating Prop 65 without disclosing this fact to parents who had purchased its products.

Scientists agree that fire retardants can harm our health, especially the health of children. Studies link exposure to these substances to developmental challenges, infertility, hormone disruption and more; some fire retardants are suspected to cause cancer. A 2014 study by EWG and Duke University found that every mother and child tested had been exposed to a toxic fire retardant; on average, the children had five times the exposure of their mothers.

There are safer ways to meet flammability standards than lacing car seats with these harmful chemicals. Manufacturers can replace polyurethane foam with less flammable materials, such as “expanded polypropylene foam,” or they can encase the foam with a fire-resistant fabric. There are also fire retardant chemicals that pose lower health concerns. The U.S. Environmental Protection Agency identified two supposedly safer chemicals in a recent report. We encourage the agency and independent scientists to investigate the safety of these chemicals and urge manufacturers to find alternatives to chemical fire retardants wherever possible.

In the meantime, parents should visit car seat manufacturers’ websites, call them and research products online to learn more about what chemicals they do or do not use. Be aware that the information may not be available. The Ecology Center study is a helpful resource. Purchasing car seats from companies that promote healthier fire safety policies will help transform the marketplace.

Outside the car, while most new children’s products are made without fire retardant chemicals, foam products that families purchased more than one or two years ago likely contain them. For tips on how to reduce your family’s exposure to the chemicals, visit Healthy Child Healthy World’s Guide to Fire Retardants in Children’s Products.