‘Lost faith’: Viral study on chemicals in cookware found to have overestimated health impacts
Demonising ‘the old plastic spatula’, an American study has had to walk back its findings after falsely claiming dangerously high levels of contamination in plastic cookware.
A study showing the health risks of plastic household items has greatly overstated the dangers of everyday cookware, rattling the credibility of its publisher and drawing the value of peer-review practices into question.
In October the article – “From e-waste to living space: Flame retardants contaminating household items add to concern about plastic recycling”, published in peer-reviewed journal Chemosphere – drew global headlines after finding traces of a flame retardant used in electronics within common kitchen utensils at levels that bordered on dangerous.
Their research was soon crippled after an independent scientist found their calculations were off by a whole order of magnitude, meaning it overestimated the presence of the brominated flame retardants by a factor of 10.
For many the correction came too late, with the mistake passing unscrutinised through three layers of academic oversight before it was cited in respected publications internationally for months, including in this masthead.
While one of the study’s co-authors, Megan Liu, argued manufacturers were likely not adding flame retardants intentionally, their study indicated the black plastic from electronics were inadvertently being mixed into everyday household products through improper recycling.
The authors clarified their error on December 15, while arguing the “calculation error does not affect the overall conclusion of the paper”.
Environmental microbiology Professor Andy Ball, who leads the ARC Training Centre for the Transformation of Australia’s Biosolids Resource, was disappointed with the correction.
“I disagree with the authors. I believe that it does change the main message, and it would certainly change the potential for that paper to be published in the first place,” he said.
“I really do think that if I was in those shoes, I would be holding my hand up and saying I take full responsibility for this mistake.” RMIT Chemistry Professor Oliver Jones said it was an indictment on peer reviewers and editors, along with the original researchers.
“It’s a bit concerning that they got their maths wrong in some regard, but they missed a zero. It’s something that anyone could do accidentally, everyone’s human,” Professor Jones said.
“What concerns me is they didn’t catch it, the peer reviewers didn’t catch it, and the editor didn’t catch it. It took somebody on Reddit or something to spot the mistake.
“The science did self-correct eventually, but the problem is by the time they got that correction out there … it had already done all the news headlines.”
He argued the study had broader implications for how the scholarly peer-reviewing process was “not fit for purpose”.
“Journals are trying to, in my personal experience, push very fast peer reviews. They’ll ask for it returned within seven or 10 days, and that’s on top of your normal job,” he said. “You just don’t have time to read the thing in depth.
“It’s very easy for mistakes to slip through these days.”
Professor Jones said the study’s independence was rocked by a number of factors, namely “potential subconscious bias” due to the authors’ association with environmental advocacy body Toxic-Free Future, and incentives through the scientific community to generate research that pulls the attention of mainstream media.
“If you’re a scientist and you work in environmental pollution then you’ve got an incentive, theoretically, to find pollution. That’s where you get your research funding from, and it’s where you get your media engagement from,” he said. “You just have to have a bit of perspective on things.”
The original study tested 203 household items that are common in the US, including toys and cookware, for the fire retardant chemical Decabromodiphenyl ether, dubbed BDE-209.
BDE-209 was found in 85 per cent of the items, a figure which remains undisputed despite the concentration being far lower than first indicated.
The plastics study is the culmination of a string of high-profile errors by Chemosphere, which has reportedly retracted eight articles and offered more than 60 expressions of concern over its own works since April.
