Comment by Mordisquitos
1 day ago
I'm amazed that wasn't taken into account! Many years ago, in the final year of my Biology degree, I did a paid summer internship at an Evolutionary Biology lab here in Spain, assisting in a project where they were researching relationships between metal ion accumulation (mostly zinc) and certain SNPs (≈"gene varieties"). A lot of my work was in slicing tiny fragments of deep-frozen human livers and kidneys in a biosafety cabinet over dry ice.
The reason I bring this up is because the researchers had taken the essential precaution of providing me with a ceramic knife to do the cutting (and platic pliers), to eliminate the risk of contaminating the samples with metal from ordinary cutting implements.
That some research on microplatics did not take into account the absolutely mental amount of single-use plastic that is involved in biological research, particularly gloves of all things, boggles the mind.
> single-use plastic that is involved in biological research
The samples were not contaminated by plastic in the gloves. Latex gloves don't contain plastic, they're made from natural rubber. Nitrile gloves also don't contain plastic, although they're very similar to plastic.
The contamination that this study found wasn't microplastic contamination. The gloves weren't adding microplastics. The gloves were adding stearates, which aren't plastic, but look like microplastic in many of the methods for measuring microplastics.
>> I'm amazed that wasn't taken into account!
This was taken into account: https://news.ycombinator.com/item?id=47563392
You found a paper saying that contamination is possible. That doesn’t mean that most of these plastic studies are doing the necessary controls, let alone the (almost impossible) task of preventing the contamination in a laboratory setting where nanomolar detection levels are used to make broad claims.
Are more “controls” what is necessary here? The problem wasn’t plastic contamination, it was the presence of stearates. Distinguishing between stearates and microplastics sounds like a classification problem, not a control problem.
There is practically universal recognition among microplastics researchers that contamination is possible and that strong quality controls are needed, and to be transparent and reproducible, they have a habit of documenting their methodology. Many papers and discussions suggest avoiding all plastics as part of the methodology, e.g. “Do’s and don’ts of microplastic research: a comprehensive guide” https://www.oaepublish.com/articles/wecn.2023.61
Another thing to consider is that papers generally compare against baseline/control samples, and overestimating microplastics in baseline samples may lead to a lower ratio of reported microplastics in the test samples, not higher.
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Luckily HN software developers, the foremost authority on literally every subject imaginable, are here to bless the world with their insights.
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Not OP, but:
> "You found a paper"
johnbarron didn't find it. The authors cited it as foundational to their own work. it's ref. 38 in the paper under discussion. From the paper: "this finding had not been reported in the MP literature until 2020, when Witzig et al. reported that laboratory gloves submerged in water leached residues that were misidentified as polyethylene."[1]
> "most of these plastic studies are [not] doing the necessary controls"
which studies? The paper they linked surveys 26 QA/QC review articles[1]. Seems well understood.
> "a laboratory setting where nanomolar detection levels are used to make broad claims"
This is like saying "miles per gallon" when discussing weight. "nanomolar detection levels"...microplastics are individual particles identified by spectroscopy, reported as particles per mm^2. "Nanomolar" is a dissolved-species concentration unit. It has nothing to do with particle counting. (I, and other laymen, understand what you mean but you go on later in the thread to justify your unsourced and unjustified claims here via your subject-matter expertise.)
> "(almost impossible) task of preventing the contamination"
The paper provides open-access spectral libraries and conformal prediction workflows to identify and subtract stearate false positives from existing datasets[1]. Prevention isn't the strategy. Correction is. That's the entire point of the paper they linked and the follow-up in [2]
[1] https://pubs.rsc.org/en/content/articlehtml/2026/ay/d5ay0180...
[2] https://news.umich.edu/nitrile-and-latex-gloves-may-cause-ov...
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>> That doesn’t mean that most of these plastic studies are doing the necessary controls
That was never my argument. Read it again.
> I'm amazed that wasn't taken into account!
Agreed. While I didn’t anticipate this myself, nor would have likely figured it out myself, I also don’t expect my claims to influence global policy.
The scientists who failed to realize this do expect that, so the standards we expect from them need to be higher in accordance with that.
>>That some research on microplatics did not take into account the absolutely mental amount of single-use plastic that is involved in biological research, particularly gloves of all things, boggles the mind
What boggles the mind is you commenting on an article you clearly did not read...stating something that is not there...
The article starts with this:
"Nitrile and latex gloves that scientists wear while they are measuring microplastics may lead to a potential overestimation of the tiny pollutants, according to a University of Michigan study."