[schobi]

Summary: dry contact with nearly any laboratory glove will lead to sample contamination and over estimation of microplastics. They found one type of clean room gloves that contaminate less.

Is there any indication on how bad this really is?

[martiuk]

Around 2000 to over 7000 false positives per mm^2 based on the type of glove. Essentially, regular lab gloves shed enough particles to swamp microplastic measurements to warrant switching to clean room gloves for this type of analysis.

[ginko]

Shouldn't any lab analysis have control samples to detect environment contamination like this?

[AlpinMouton]

It's difficult to avoid contamination, since everything (samples, containers, equipements, etc) will have been in contact with glove at least once, and good decontamination is very hard.

[nom]

Yes, exactly, that's why you use control samples to get the baseline.

[DangitBobby]

You see how it's a bit of a self-starting problem?

[ginko]

Let's say you want to determine the amount of microplastics in ocean water samples.

You'd create a control by creating saline solution with distilled water and sodium chloride. Then you treat both the control and your sample(s) the same way in the analysis.

Surely something should tick you off when the microplastic levels aren't much lower in your control compared to your actual sample?

[DangitBobby]

They are handling both the control and the sample with gloves. Which is the same way. They are contaminating both. It's useless to argue about how contamination could have theoretically been avoided in an alternate past in hindisght. You don't realize there's a potential contaminant until you do and then you mitigate it. I'm sure they are smart enough now that they realize they are systematically introducing contaminants, they will be able to figure out how to control for it.

[mrob]

Freshly cleaved mica has an extremely clean and flat surface.