Babies and children up to age four could be breathing in plasticizers and other chemicals from their mattresses while they sleep, a Canadian study suggests.
Federal regulations set limits on some phthalates or plasticizers, which are substances added to products to make them more flexible.
Miriam Diamond, an environmental chemist at the University of Toronto, and her team designed an experiment to estimate how much of the compounds are released into a child's sleeping area from 16 different mattresses.
In Tuesday's issue of the journal Environmental Science & Technology, the researchers reported that two of the mattresses tested did not comply with Canadian regulations for two phthalates and two plasticizers in consumer products.
The regulations are based on potential harm to human health and the environment. For instance, when babies are exposed to phthalates in house dust, studies suggest it is associated with higher risk of asthma.
Miriam Diamond cuts a sample of a mattress in the laboratory at University of Toronto. (Kemeisha McDonald/University of Toronto)Diamond said she was motivated to try to understand the impact of the chemicals on kids, given that babies sleep up to 18 hours a day.
"They're in intimate contact with their mattress in that sleeping environment," Diamond said in an interview. "Kids inhale 10 times more air than adults, so that gives the opportunity to be exposed to airborne chemicals a lot more than adults."
The study did not include brand names, but the researchers said mattresses were purchased for $50 to $105 from leading retail stores in Canada.
Diamond's lab has previously reported on how children can be exposed to phthalates and plasticizers by inhaling them, absorbing them through the skin, ingesting dust or by putting their hands, clothes and toys in their mouth.
The researchers said the chemicals found in mattresses are known to be associated with developmental and hormonal disorders.
Diamond suggested that parents wash bedding and pyjamas frequently, since they are protective barriers from mattresses, and cut back on the number of items on children's beds, like toys.
The researchers also suggested manufacturers improve the oversight of their products so they comply with regulations and their own product certifications. They should also improve manufacturing practices to minimize unintentional contamination, and to only use such chemicals when necessary.
Specifically, the researchers found one mattress contained high levels of tris(2-chloroethyl) phosphate, or TCEP, which has been prohibited from use in Canada since 2014 and is considered a carcinogen.
Chris Carlsten, a medicine professor at the University of British Columbia, has studied how phthalates can harm human airways.
"These are chemicals I think we all should justifiably not want to have in these mattresses of children," said Carlsten, who was not involved with the latest research.
He called the recommendation to use non-toxic bedding and clothing "wise," adding that holds for adults, as well.
Children are more susceptible given their developing bodies, Carlsten noted.
Health Canada said it is carefully reviewing the findings and other available information to identify any risks to human health or non-compliance with legislative or regulatory requirements, and that it will "take appropriate action to protect people in Canada."
Funding for the research was provided by a University of Toronto Fellowship and Ontario Graduate Scholarship and by the Natural Sciences and Engineering Research Council of Canada.\