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0 pointsars2y ago0 comments

The PFAS sticks to glass, but doesn't absorb into the glass. Meaning the PFAS isn't coming from the straw manufacture, but rather later - perhaps during washing.

Meaning they are not being careful to distinguish between PFAS as included by the manufacturer, and PFAS that comes later.

So all the PFAS they found - is that just PFAS from the local water supply? If so the entire research is called into question.

(I highly doubt glass straws are being marketed as easy clean - the coating doesn't stay, you have to reapply it, so I doubt they would bother spending that money on straws for something temporary.)

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blamazon2y ago· 2 in thread

Points taken on methodology, don't have enough knowledge to speak much further on it constructively but I would say my intuition is that "stuck to" is not that much different to "absorbs into the outermost layers of" although I would like to know more about what's going on molecularly, and will look into it. I'm also not sure the distinction between PFAS introduction in manufacturing vs washing/distribution is that important to this study - does that distinction matter to the end user of the straw who is looking to reduce PFAS intake?

On coatings: If you're a glass factory who has been pumping out say, PFAS coated glass beakers for years and then you decide to get into the straw game, why not coat those too if your beaker customers like the coating? Doesn't seem like much additional cost at 'shipping container scale' if you're running the coating shop anyway. And, I believe polymeric glass coatings can be attached 'for life' these days. Again I'm not an expert but I believe they are applied to smart phones, solar panels, exteriors of buildings, etc.

Cynically, a coating doesn't even have to stick around to be important enough to spend money on. Maybe it falls off immediately but just keeps the straws smudge free during packing with 20% less time on washing or something. Given the social understanding to wash new food grade stuff before use, I don't believe is a situation out of the ordinary.

I'd like to know more about all this as someone who uses glassware for ingested items - will do more research.

arsOP2y ago

> I'm also not sure the distinction between PFAS introduction in manufacturing vs washing/distribution is that important to this study

Because one applies to everyone, and the other only to those people who live in the same place as where the test was performed.

Controlling for contaminants is like rule one of this kind of study.

> If you're a glass factory who has been pumping out say, PFAS coated glass beakers for years

You're not. Those are not common things, they are specialty items. And most likely applied elsewhere, not as part of a glass factory anyway.

> And, I believe polymeric glass coatings can be attached 'for life' these days.

If that were true then the PFAS isn't leaving the glass to go into the human, which just calls the study even more into question. But I doubt there are any coatings in the first place (on glass), the PFAS came from elsewhere. (On the paper straws though, I totally believe the PFAS was applied deliberately - but this study is not where I'm learning that.)

swishycoconut2y ago

This patent seems to suggest that hydrophobic coatings on reusable drinking straws are a thing. They apply it to make the straws easier to clean for reuse. https://patents.google.com/patent/EP3738479B1/en

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