Popular science research has shown that black plastic in common household items often contains harmful flame retardants. But now researchers say the findings contain a significant mathematical error.
The Canadian chemist first raised the alarm in an interview on December 11 National Post. In essence, exposure to the black plastic flame retardant appeared to be approaching the Environmental Protection Agency’s (EPA) limit for what the agency considered safe. However, the numbers dropped by a factor of 10 – the EPA’s safe exposure limit was higher than originally reported, meaning black plastic does not pose such an obvious threat to human health.
The original team of researchers published a correction in the journal Hemosphere December 15, taking readers through the error.
Even so, experts agreed that avoiding black plastic kitchenware, takeout containers, toys and other products is still a smart idea – especially if that plastic touches food.
“It does not change the general trust in newspapers.” “The point they made was a legitimate point: that these substances should not be in these items,” he said Joe Schwarz, Ph.Dprofessor of chemistry and director of the Office of Science and Society at McGill University, who found the error.
“However, when publishing a scientific paper, you have to be specific, especially when warning people about potential toxins,” he said. Health.
In the original study, the researchers wanted to investigate whether toxic flame retardants could enter household items through the recycling of electronic waste.
They tested 203 products – from plastic spatulas to children’s necklaces – for two types of flame retardants known to cause health problems: brominated flame retardants (BFRs) and organophosphate flame retardants (OPFRs).
Manufacturers put these flame retardants in the black plastic used in electronics to prevent fires. However, when these products are recycled, flame retardants can get into the new items without people or manufacturers knowing.
The researchers found that 85% of the products they tested contained flame retardant chemicals in general, and 65% contained a mixture of both classes of flame retardants. The highest amounts of flame retardants were found in sushi trays, toy cars and kitchen sinks.
Fourteen of the 203 products tested contained decabromodiphenyl ether (BDE-209), a flame retardant banned by the EPA and linked to cancer. This chemical was subject to correction.
The researchers’ error was unrelated to the presence or amount of BDE-209 in the items — instead, the researchers miscalculated the amount of the chemical that the EPA considers safe, called the reference dose.
For an adult weighing 60 kilograms (about 132 pounds), the EPA’s reference dose for oral exposure to BDE-209 is 420,000 nanograms per day. But the researchers happened to have that figure of 42,000 nanograms per day.
Because the data showed that people using black plastic could be exposed to 34,700 nanograms of BDE-209 per day, the researchers were alarmed. It appeared that people were dangerously close to the threshold of safe exposure to flame retardant. However, with the corrected figure, this exposure to BDE-290 does not approach the reference dose.
Despite the error, the study’s findings and recommendations still stand, said the study’s lead author Megan Liuscience and policy manager at Tokic-Free Future. BDE-209 was just one of 11 different flame retardant chemicals found in plastics, she said, and the fact that there are flame retardants in these products at all is a concern.
“We remain very concerned that highly dangerous toxic flame retardants – especially those that accumulate in humans or in the food chain – have been found in black plastic kitchen utensils, food containers, toys and hair accessories,” Liu said. Health. “They have no reason to be in these products to begin with and should be banned.”
In 2021, the EPA banned the production, processing or distribution of BDE-209 in the US The agency phased out the class of chemicals it belongs to — polybrominated diphenyl ethers (PBDEs) — more than a decade ago, calling PBDEs “persistent, bioaccumulative and toxic to both humans and the environment.” More recently, a study published in April found that participants with the highest blood levels of PBDEs were 300% more likely to die from cancer.
“Kitchen spatulas and things like that don’t need flame retardants,” Schwartz said.
In fact, using any type of plastic in the kitchen can be dangerous, regardless of whether it contains flame retardants, he said Jaime Ross, Ph.Dassistant professor of neuroscience at the University of Rhode Island.
“Even without flame retardants, I still wouldn’t use plastic for cooking because the heat can cause the plastic to degrade and allow the microplastics and nanoplastics to be consumed by the vector,” she said. Health. “We know heat and plastic don’t go well together.”
A report released earlier this year found that plastic contains more than 16,000 chemicals, with 4,200 of them linked to negative effects on human health or the environment.
“Plastic is a chemical,” Ross said. “Every time you ingest any type of plastic, you give it the potential to move around your body and enter deeper tissues, including the brain.”