Huge math error corrected in black plastic study; authors say it doesn't matter

https://arstechnica.com/health/2024/12/huge-math-error-corrected-in-black-plastic-study-authors-say-it-doesnt-matter/

by ars • 2 years ago

173 112 2 years ago

isaacfrond• 2 years ago

I was actually seriously considering tossing my kitchenware. It was only me inertia that kept me from it. I wonder how long the afterlife of this one is going to be; reminds me of the autism causing vacines hoax

crazygringo2• 2 years ago

Well, the original post on HN was front page. This one is collecting... barely more than a point an hour.

So if HN doesn't even care...

marssaxman3• 2 years ago

The discussion of this topic five days ago received 128 points and 174 comments:

https://news.ycombinator.com/item?id=42400008

jkestner• 2 years ago

For sure. In the face of bigger systemic changes that feel out of our control (eating better, working less, affordable health care), we’ll try every “one weird trick”.

moron4hire• 2 years ago

It's not a hoax, though. Vaccines causing autism was. While the level of the carcinogen wasn't what they thought it was, it's still significantly higher than the 0 that it should be, because the only reason it's there at all is because the companies are recycling plastic from electronics. I think that the researchers saying it doesn't change their conclusion is reasonable.

If you had told me that Cocoa Krispies were 50% rat feces, but then came back and said you'd made a mistake and was off by an order of magnitude, it's only 5%, I think it would be pretty reasonable to not update your conclusion that Cocoa Krispies were significantly contaminated with rat feces.

pfdietz6• 2 years ago

the carcinogen

I love how threat inflation turns chemicals from innocuous to deadly in the absence of any strong evidence.

No, we cannot say this chemical is a carcinogen. Read the wikipedia page.

https://en.wikipedia.org/wiki/Decabromodiphenyl_ether

In 2004, ATSDR wrote "Nothing definite is known about the health effects of PBDEs in people. Practically all of the available information is from studies of laboratory animals. Animal studies indicate that commercial decaBDE mixtures are generally much less toxic than the products containing lower brominated PBDEs. DecaBDE is expected to have relatively little effect on the health of humans."

phoronixrly5• 2 years ago

Idk, plastic in contact with hot/acidic food/surfaces gets a no from me. Even before the apparently incorrect paper.

Really, you bought Tupperware? Even if you don't ask yourself whether any contaminants were released by it in your food, maybe the fact that it gets stained by pasta sauce to a point where it becomes an Internet meme makes it shitty kitchenware?

Even without exposure to food, plastic deteriorates with sunlight exposure or even just age... Why spend money on stuff like this? Buy a porcelain salad bowl instead, get a wooden spatula, put some oil on it so it endures washings.

Tomte• 2 years ago

I did. And today I wouldn‘t, but still, the silicone set is nicer than the hard plastic one. So I don‘t mind too much.

marssaxman3• 2 years ago

Likewise: after throwing out all of our cheap black plastic utensils, we replaced them with much nicer wood, metal, and silicone implements. It was a pleasant little upgrade, even if it wasn't strictly necessary; no regrets.

emilamlom• 2 years ago

They're $5 spatulas that melt and shed bits of plastic over time. Wood, silicon, or stainless steel are all better and not too much more expensive. Even if this was a hoax (which it's not), there's plenty of reason to upgrade anyways.

dfxm12• 2 years ago

As long as some famous nude model doesn't make it a personal crusade to spread disinfo, I don't think it'll quite reach "autism causing vaccines" levels.

croes5• 2 years ago

So you are ok with getting a dosis of 8% of the EPA limit when alternatives with much less toxicity exist?

EE84M3i• 2 years ago

Was this originally discovered by Adam Ragusea? He mentioned it in his video about it before all the press came out about the error, and said he emailed the authors.

thebetatester• 2 years ago

I wondered that as well. Shame they didn't give him credit if he truly was the first one to point it out.

savanaly• 2 years ago

I've never been too sure how closely he's reading those papers he refers to in his informational vids; if he actually discovered a flaw himself from reading one that is highly indicative he's doing a good job!

thaumasiotes3• 2 years ago

Obviously it doesn't matter. If it mattered, the paper might get retracted.

readthenotes12• 2 years ago

You forgot the sarcasm font there....

phoronixrly5• 2 years ago

It's not even sarcasm. The authors state that the correction does not alter the conclusion

coreyh14444• 2 years ago

Also see this from Ethan Mollock on Twitter: https://x.com/emollick/status/1868329599438037491 -- o1 was able to spot the error on the first try. It has now led to a whole initiative called the Black Spatula Project: https://amistrongeryet.substack.com/p/the-black-spatula-proj...

fnqi8ckfek2• 2 years ago

That's actually crazy. How does it do it? I thought that these machines only "predict the next word".

dartos2• 2 years ago

They are.

They’re just really really good at it.

That’s how ML is. “Prediction” is just another word for really really good guess.

oidar2• 2 years ago

People are missing the forest for the trees on this one. I agree with the author here - unfortunate error, but the conclusion should lead to the same actions.

jtc331• 2 years ago

At minimum it changes the urgency for individuals with existing cookware.

phoronixrly5• 2 years ago

We are talking about black plastic spatulas and spoons, right? Existing cookware? Non-plastic replacements' price is less than 5 euro at IKEA, possibly less at local kitchenware stores... What urgency would there be apart from 'oh I need to pick up a wooden spatula for eur 0.50 next time I go to IKEA'...

coldpie5• 2 years ago

So the main concept people are having a disagreement here is around the concept of risk versus hazard. A thing can be a hazard, without being a risk. The data you should use to decide to take action is the amount of risk, not the amount of hazard. In the specific scenario of humans ingesting potentially dangerous substances, usually risk is directly related to the amount of exposure to a hazard. In other words, you can think of it as "risk = hazard * exposure."

For example:

- If you're a smoker, your exposure to the hazardous substances in cigarette smoke is sky-high. The risk to your health of being a smoker is so high and so clear that societies spend millions of dollars to try to convince people of the risk.

- If you're living with a smoker, but not a smoker yourself, then your exposure is lower, but still high enough to be actionable. So we see indoor smoking bans and 2nd hand smoke information also included in anti-smoking campaigns.

- If you're walking down the sidewalk and pass by a smoker for three seconds, you're still encountering the exact same hazard, but your exposure is so low that the risk is not really actionable. It's not like we see big public campaigns about crossing the street to avoid the risk of 3 seconds of exposure to second hand smoke. That's because the risk isn't there.

- Someone smoking in their house 50 miles from you is obviously zero risk to you at all, even though the hazard still exists.

You can see the same kind of pattern everywhere: car exhaust is the same hazard everywhere, but whether it's a risk worth actioning depends on whether you live in a dense urban center, or next to a busy freeway, or out in the exurbs.

So back to the plastic stuff. The study authors were claiming that the level of risk was high enough to justify everyone in the world throwing their utensils away and buying brand new ones. When it came out that the exposure factor of their "risk = hazard * exposure" formula was actually off by a factor of 10, they... stuck with the exact same story? I don't know, man. The original claim was below the acceptable risk threshold, and now it's even ten times lower than that. Surely that has some impact on the level of risk? Does this drop the risk from "smoker" to "passing by a smoker for 3 seconds"?

The distinction matters when deciding how much effort mitigating this risk requires: should I throw everything out right now, or just buy something else when my current ones wear out, or is the risk actually so low that it really does not matter? If I replace them, what is the level of risk of the things I replace them with? Should society put in the effort to ban these chemicals? What are the pros/cons of that? Are the risks mitigated worth the costs?

The authors' refusal to acknowledge this really makes me doubt that their conclusion is not affected by some kind of bias. The jury's still out, sure, but I'm not yet sold on their risk claims.

oidar2• 2 years ago

I think the paper's authors contribution to common knowledge here isn't the risk/hazard/exposure calculation - it is that there is a risk at all.

IshKebab2• 2 years ago

Why? The risk is much much lower than they stated.

ternnoburn5• 2 years ago

Because risk is still high. It's not astronomically high, but it's still quite high.

And it's trivial to replace with materials that don't have that risk. For a couple bucks you can remove fire retardants from your food. Why wouldn't you?

JoshGG2• 2 years ago

What amount of fire retardants would you like in your food? How about zero? I would like zero.

These have already been banned in CA from furniture because it creates household exposure. Why would it be ok in cooking utensils?

BTW the chemicals don’t actually prevent house fires it’s basically an industry scam to put them into products.

infecto3• 2 years ago

Your information is incorrect.

Flame retardants were introduced into everything because of CA and Federal laws requiring items to smolder and not catch fire. While I don't believe flame retardants should be as prevalent as they are today, I also think its unfair to say they don't prevent house fires. They absolutely have done some saving but I don't think across the entire population its a net positive. These rules were originally put into place because of a number of high profile cases where kids died, the biggest vector were beds, people smoked and dropped the butt on their mattress and poof.

That rule in CA is in the right direction, glad they are helping right some of the wrong they did but it is still in everything. I think its more helpful to paint the accurate historical picture as opposed to yours which is using hyperbole to generate a reaction.

JoshGG2• 2 years ago

“”” Flame retardants were widely adopted in the 1970s, when in-home smoking was more prevalent and electronics frequently overheated. New research, however, shows that flame retardants are not very effective at slowing or preventing fires. “””

https://www.sfenvironment.org/how-can-i-avoid-flame-retardan...

IshKebab2• 2 years ago

Zero is an impractical goal. I would like zero cars on the road. Zero litter. Zero CO2 emission. Zero idiots on the internet.

Sadly we both live in the real world. "A small fraction of the recommended limit" is perfectly acceptable.

ternnoburn5• 2 years ago

Is 8% a small fraction? I don't think it is... sure it's not 80%, but it's definitely not 0.08% either.

exabrial• 2 years ago

it’s basically an industry scam to put them into products.

This assertion cannot possibly be correct, regardless of the study

OJFord4• 2 years ago

Ars has reached out to the lead author, Megan Liu, but has not received a response. Liu works for the environmental health advocacy group Toxic-Free Future, which led the study.

Clearly the authors had their conclusion even before doing the study, so of course the error doesn't affect it.

phoronixrly5• 2 years ago

No. The authors state that their conclusion is not altered by the change in calculations. As per TFA:

"This calculation error does not affect the overall conclusion of the paper," the correction reads. The corrected study still ends by saying that the flame retardants "significantly contaminate" the plastic products, which have "high exposure potential."

ajkjk2• 2 years ago

How is that clear? Perhaps they are a group that exists to do studies like that.

kevin_thibedeau• 2 years ago

Groups that exist to do studies like that can be biased toward gainful employment and suppress anything that threatens the revenue stream.

OJFord4• 2 years ago

That is pretty much my point, yes.

ternnoburn5• 2 years ago

80% of maximum fire retardants entering food or 8% of maximum fire retardants entering food are both "too much fire retardants entering food".

Seems like the conclusion very obviously still holds, so I'd agree with the study authors here, that error doesn't alter the conclusion.

coldpie5• 2 years ago

80% of maximum fire retardants entering food or 8% of maximum fire retardants entering food are both "too much fire retardants entering food".

OK, but that's not what this study was about, right? The original claim by the authors was that these utensils brushed up against safe limits. When that turned out to be false, the claim has shifted to the safe limits are too high. But that's a different study. You need to do a safety analysis of exposures to the substance. That's not what their study did.

croes5• 2 years ago

So instead of 80% toxic limit it’s „only“ 8%.

Sorry but I don’t want any toxic material in the tools I use for food.

tbrownaw3• 2 years ago

Fun fact: oxygen is toxic in high enough concentrations.

OJFord4• 2 years ago

It's not 'toxic material', it has a toxic dose. Too much water and you die. You do want some percentage of that level of water, though.

jcranmer2• 2 years ago

On the most charitable level, the "huge math error" occurred in the calculation of the FDA's limits on exposure, so if the group feels that the FDA set its limits too high and the amount of chemicals being leached is worrying, then the math error really doesn't affect their conclusion at all.

But digging into the study, it becomes clear that the authors are really reaching in their methodology--subjecting utensils to rather implausible scenarios (when was the last time you microwaved your sushi tray?)--to try to get some samples that would exceed the limit. The hyperbolic media coverage of "ditch all your black plastics" isn't really sustained when the research finds that just a few specimens, when subjected to unusually high heat stresses, managed to just barely cross the incorrectly-calculated FDA threshold (itself likely set at a factor of a tenth to a hundredth of the lowest threshold observed to cause issues in previous studies!). That the authors aren't willing to disavow that media coverage is more telling then their unwillingness to adjust their conclusions in response to their math error.

tivert3• 2 years ago

subjecting utensils to rather implausible scenarios (when was the last time you microwaved your sushi tray?)

That's not implausible. Sushi actually tastes better a little warm than chilled.

Also I think it would make sense to test all food trays the same way, as some of those do get heated quite a bit (e.g. I've microwaved take-out noodles in plastic trays very similar to a take-out sushi trays). It's not like it's plausible that there's some special sushi-tray supply chain where they've carefully determined they can safely get away with using e-waste plastic. It's almost certain that industry consists of many takeout tray companies that each make a whole line of takeout trays for different uses using the same raw materials (e.g. the sushi cart at my employer sold sushi and hot noodle soup in black plastic trays, which plausibly could come form the same manufacturer).

EasyMark3• 2 years ago

In general with all the microplastics floating around, I found it not a large investment to divest of 95% of the plastic in my kitchen (there was a lot), including the black variety, and only cook in stainless/carbon steel, ceramic enameled cookware, and glass with wood or stainless steel utensils and only drink filtered water. It's not hard to get most of the plastic out of your kitchen at least, but there are tons of other sources; clothes, furniture, devices, etc. I'm working on minimizing some of that as well. One of the most frustrating things is you can't find a drip coffee maker with an all metal full path for the water to grounds path. Everything I looked at had a ton of plastic unless it was $700+, so I live with the ritual of the french press for now

itsdrewmiller• 2 years ago

Basically a dupe of https://news.ycombinator.com/item?id=42400008

animanoir• 2 years ago

Click bait article.

EasyMark3• 2 years ago

I would say it's a factor of 10 times less clickbaity than the click-bait of the original article if 80% to 8% is indeed correct.

spacemark• 2 years ago

Maybe it's just too early or there are other posts, but I find it an interesting insight into human behavior - supposedly intelligent human behavior - that there were hundreds of comments on the posting of the original study here at HN, the vast majority of which accepted the study's conclusion, yet there are much fewer comments on the "adjustment" to the study's conclusion.

I shouldn't be too cynical, but it's a reminder to be skeptical, always.

marssaxman3• 2 years ago

There was a discussion of this retraction last week which received many more comments: https://news.ycombinator.com/item?id=42400008

theshaper• 2 years ago

Update: "Journal that published faulty black plastic study removed from science index"

https://arstechnica.com/health/2024/12/journal-that-publishe...

syndicatedjelly• 2 years ago

On the one hand, making mistakes in basic math is reasonable cause for retraction; on the other hand, why are people defending the use of something with only 8% of the daily limit of a carcinogen? Is there some hidden benefit to using melty plastic utensils on a hot iron pan versus, say, wood or metal, both of which contribute closer to 0%?

Huge math error corrected in black plastic study; authors say it doesn't matter

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