A recent scientific study had raised concerns about black plastic in everyday items containing harmful flame retardants. However, researchers have now identified a significant mathematical error in their findings. This issue was first noted by a Canadian chemist in a December interview with the National Post.
Initially, it seemed like exposure to a flame retardant from black plastic was nearing the safety limit set by the Environmental Protection Agency (EPA). But it turns out the calculations were off by a factor of 10. This means that the EPA’s actual safe exposure limit was much higher than reported, suggesting that black plastic isn’t as much of a health threat as was initially thought.
The research team corrected their mistake in the journal Chemosphere, explaining how they arrived at the error. Despite the correction, experts still recommend avoiding black plastic kitchen utensils, takeout containers, toys, and other items, especially when these products come in contact with food. Joe Schwarcz, a professor of chemistry, emphasized that the core warning of the paper remains valid—such compounds shouldn’t be in these products. He also pointed out the necessity for precision in scientific publications, especially when public health is concerned.
The original study aimed to see if toxic flame retardants from recycled electronic waste could end up in household items. They tested 203 products, including plastic spatulas and toy necklaces, for brominated flame retardants (BFRs) and organophosphate flame retardants (OPFRs), which are known to cause health issues. The team discovered that 85% of the products contained flame retardants, and 65% included a mix of both types. The highest concentrations were found in a sushi tray, a toy car, and a kitchen peeler.
Fourteen products tested contained decabromodiphenyl ether (BDE-209), a flame retardant banned by the EPA due to its link to cancer. The team’s error was in calculating the EPA’s reference dose for safe exposure to BDE-209. For someone weighing about 132 pounds, the correct reference dose is 420,000 nanograms per day, but researchers mistakenly stated it as 42,000 nanograms. This led to a mistaken impression that exposure levels from black plastic were dangerously high. With the corrected figure, actual exposure levels are not nearing the unsafe zone.
Lead study author Megan Liu still finds the presence of various flame retardants in household products worrisome. She remains concerned about these hazardous chemicals, especially those that accumulate in living beings or the food chain, showing up in black plastic kitchen utensils, food containers, toys, and hair accessories. Liu argues they should be eliminated from such products altogether.
In 2021, the EPA banned the use of BDE-209 in the U.S. and had already phased out polybrominated diphenyl ethers (PBDEs) over a decade ago due to their persistent, bioaccumulative, and toxic nature. A recent study revealed that high levels of PBDEs in blood significantly increase cancer mortality risk.
Joe Schwarcz believes kitchen utensils don’t need flame retardants, and Jaime Ross, a neuroscience professor, cautions against using any plastic for cooking. Heating plastic can lead to degradation, allowing microplastics and nanoplastics to be consumed. Plastics themselves contain more than 16,000 chemicals, with over 4,200 linked to negative health or environmental effects. Ross emphasizes that ingesting plastic can lead to it spreading through the body, reaching deeper tissues, including the brain.
