By Zoe Kolenovsky
Researchers are finding more evidence that kids are likely exposed to toxic chemicals while they sleep, according to a recent pair of studies.
The main source of these chemicals is mattresses, which can contain harmful substances such as phthalates, flame retardants and the toxic “forever chemicals” known as PFAS.
Mattresses typically emit these chemicals, which are linked to a range of health harms. And it happens with many popular babies’ and children’s mattress brands. The chemicals release into the air from solids, creating an exposure risk for children and others in a household.
Children have a higher exposure risk than adults, since they spend over a third of their time in their beds. Before adolescence, they may sleep between nine and 14 hours each day. Babies can nap as much as 17 hours a day, typically in their cribs.
Kids are also particularly susceptible because of their still-developing bodies. Early life exposure to toxic substances, even in small amounts, can cause health issues like asthma and disrupt development of brain function.
For the first study, a team led by University of Toronto researchers tested bedroom air and mattresses for several kinds of harmful chemicals, including some phthalates and flame retardants. Bedrooms of 25 kids ages 6 months to 4 years made up the sample.
The researchers detected several chemicals in both air and mattresses. Levels of phthalates and flame retardants were higher in mattresses, indicating they were an important source of exposure.
Phthalates and flame retardants are semi-volatile organic compounds, or SVOCs. They’re found in a wide range of common household products, such as cleaning supplies and furniture. They then vaporize, or enter into the air, and can be easily breathed in or absorbed through the skin.
SVOCs measured in homes have been linked to poor health outcomes, including some respiratory conditions such as asthma and allergies, as well as harm to the nervous system, hormone disruption and increased risk of cancer.
In mattresses, phthalates are usually found in undisclosed “fragrances” added to filling and toppers to mask odors. Mattress covers can be made with vinyl chloride and polyvinyl chloride, better known as PVC, which also contains phthalates.
Flame retardants are used in some mattresses, as they’re designed to slow a fire’s spread. But there’s no clear evidence they really work. Some manufacturers have started to phase them out because of their health risks. Several can harm the reproductive, hormone and nervous systems. And because they are released over long periods of time, they can’t be aired out.
Organophosphate ester flame retardants, or OPEs, sometimes replace other flame retardants that have been banned. And they can also be harmful – they have been linked to premature birth, impaired thyroid function and other harms.
The researchers found kids were most likely exposed while sleeping, because the air near their beds contained the highest levels of phthalates and OPEs.
In a separate study, researchers – including several from the first study – analyzed whether mattresses were, in fact, the source of the chemicals.
They tested 16 children’s foam mattresses purchased from major North American retailers between 2021 and 2024. They reported the presence of SVOCs in all 16, in one case in an amount exceeding Canadian regulatory limits. Another had high levels of a flame retardant that Canada banned in 2014.
The study’s authors then conducted a simulation, reporting that chemicals present in mattresses do move into the air. They also found that warmth and higher body weight lead to the release of more chemicals.
The two studies were published recently, one in the Environmental Science & Technology Letters journal and the other in the Environmental Science & Technology journal.
What you can do
In general, it’s best to buy mattresses and mattress covers without PVC or vinyl and avoid fiberglass and polyurethane where possible. Check out EWG’s Healthy Living Home Guide on mattresses for more tips on how to find options to keep your family safe.
Cleaning mattresses and bedding regularly with a high-quality vacuum can help remove buildup of dust, which can contain particles containing toxic chemicals.
The studies’ authors recommend washing children’s bedding and clothing frequently, since they can act as a barrier to reduce chemical exposures. The authors also encourage limiting the number of toys and other items in the bed, since harmful substances can build up in them.