Glass bottles found to contain more microplastics than plastic bottles
The researchers found an average of around 100 microplastic particles per liter in glass bottles of soft drinks, lemonade, iced tea and beer. That was five to 50 times higher than the rate detected in plastic bottles or metal cans.
"We expected the opposite result," Ph.D. student Iseline Chaib, who conducted the research, told AFP.
"We then noticed that in the glass, the particles emerging from the samples were the same shape, color and polymer composition—so therefore the same plastic—as the paint on the outside of the caps that seal the glass bottles," she said.
The paint on the caps also had "tiny scratches, invisible to the naked eye, probably due to friction between the caps when there were stored," the agency said in a statement.
This could then "release particles onto the surface of the caps," it added.
https://phys.org/news/2025-06-glass-bottles-microplastics-plastic.htmlOpen linkView original on lemmy.world
96 replies
So nothing coupled to the glass but rather the cap having a extra plastic layer on the wet side.
Sounds like we found the issue, now it's just a matter of producers improving the caps
Only if it doesn’t cut it to record profits
Only if it somehow increases profit. FTFY
Nah ill just spend $50 to have a Congress member introduce a bill to make regulating microplastics illegal
meanwhile in the EU we'll move back to cork
Don't worry the cork will still be filled with microplastics from the soil used to grow it to the adhesive used to bind it.
Ha! Good one.
Just use the plasticbottlecaps.
No, the paint on the outside.
Yes. So many people are misunderstanding this article... The microplastics are on the inside, in the drink, and they are bits of the paint from the exterior of bottle caps that stuck to the inside of other caps when the caps were all jumbled together in big bags before they were placed on the bottles.
That would be far more intuitive, but it's not that - it's the painted logo on the outside.
In a bizarre twist, plastic bottles have been found to contain alarming levels of microglass.
You mean sand?
I don't like microglass
Yea it's coarse and everywhere
https://youtu.be/2tLf1JO5bvE
jajaajajajajajajajjjaaj
Step 1: Invent plastic bottles
Step 2: Pocket the cash
Step 3: Things got bad? Outsource the clean-up to the end user in the form of recycling
Step 4: Increase prices to account for recycling
Step 5: Laugh as the idiots actually recycle your shit
Step 6: Throw the whole shebang in the ocean or in landfills
Step 7: Pocket some more cash
Step 8: Pat yourself on your shoulder. You've done some capitalism.
You forgot the step where they invent a logo that looks almost the same as the recyclable logo and stick it on all plastics but it doesnt mean its recyclable but instead just says what kind of plastic it is.
Lets go back to corks
As someone in a cork industry, you really don't want that.
What is this teasing? Elaborate.
It takes a lot of effort to soak the corks.
Its really hard to soak my own cork, so I just get my girlfriend to soak my cork instead.
I also get this guy's girlfriend to soak my cork
She does have a lot of experience soaking cork
We know
Care to expand on why? I've had corks dissolve and break if I didn't finish the drink quickly enough, just on liquor bottles that went unused for a year or so. Any other reason?
Slightly educated guess. True organic cork is produced by cutting the bark off specific trees. There are limited climates it grows. I would guess the scale with which we produce bottled drinks would require significantly more trees and labor that we currently have. And thus cork prices would skyrocket.
And you can't really close them again.
Why?
Corka Cola.
Man on the surface this reeks of inside payoffs. I guess the technicality is plastic caps on glass bottles?? Which seems weird and nothing I've ever seen. Unless they're referencing the seal on the inside of some metal caps on glass bottles? Either way, seems suspect. I'd assume that overall drinking from glass is safer, as with plastic on any timeline you're dealing with the plastic breaking down and leaching chemicals and micro plastics into the liquid, which wouldn't be an issue with glass.
Not plastic caps, plastic paint. The printing on bottlecaps is a polymer and it gets scuffed.
Odd. I would have thought that the paint, being on the exterior, wouldn't leak into the beverage contained inside the glass.
But apparently, they found that blowing air over the caps reduced the amount of detected contamination by 60 per cent. So it seems like an easy fix that manufacturers can implement inexpensively (literally just an electric fan)
There is a real reason that the caps are painted. Glass beverage bottles are usually stored in a crate and grabbed from the top, so the design on the lid is what restaurant or store employees used to distinguish what drink is contained within it. This allows employees to distinguish similar-coloured drinks (e.g. Coca-Cola vs Pepsi or two different brands of beer) just from looking down at the top of the bottle.
But there probably is a way to paint them without using plastics
Which is easier? Squatting down to count how many caps say "Coca-Cola" or counting the number of bottles with red caps?
Put a sticker on it after it's sealed.
The reason for paint is because the cheap, mild steel they use for bottle caps will begin to rust in minutes - literally minutes - if it is not protected from the oxygen in the air. The paint is necessary to keep the caps from oxidizing and leaving rust marks on everything they touch.
The color and logo on the caps are simply for marketing purposes.
Unfortunately, it's probably not going to be an electric fan, but compressed air. Even more unfortunately, compressed air turns out to be a major cost factor due to the cost of running compressors, which might prevent adoption.
The original paper mentions blowing the caps out with an "air bomb", which I'm pretty sure is a mistranslation stemming from the French term "Bombe d’Air Comprimé", i. e. an air duster, a can of compressed air. In an industrial setting, you'd use a compressor for this, naturally.
How exactly would that happen if the cap is ON the bottle?
You make a lot of them. They are flat. They get painted, they get punched out, (this is where the ‘magic’ happens) they get shuffled around to load into machines to put them on the bottles, they go through the machine and they get clamped to the bottles.
There! Instant plastics!
The paint itself on the outside of the bottle cap. The ultra thin layer of (apparently polymer a.k.a. plastic) paint that make the cap not just metal colored.
I thought they were talking about the seal.
For the people in the comments who either won't or seemingly can't read the article: The paint on the top of the caps is plastic-based and before they're put on the bottle they're stored in a big jumbled up pile where the paint chips off and coats the caps in tiny flakes. When the cap gets put on the bottle, the flakes on the bottom of the cap get washed off into your drink. Studies show that washing the caps first dramatically reduces the micro-plastic contamination.
Just pour it from the glass bottle to the plastic bottle. Problem solved
Title seems misleading.
As the micro plastics were found on the paint outside the bottle cap. It seems complicate that that ended on the drink itself. Unless you are licking the bottle cap it doesn't seem that relevant.
No, the microplastics were found in the content of the bottles. The cap thing is where they come from. As a reply to you explained, the microplastic from the top of a cap is scratched by another cap and ends up on the bottom of yet another cap.
Paint scratches off the outside, then sticks to the inside and makes it into the drink.
Landing on the outside surface though, how is it making it through the cap?
Caps aren't stored individually, they scratch each other all the way into the capping machine, see this cap feeder for example:
https://yewtu.be/watch?v=4717zbMCMHU
https://youtu.be/4717zbMCMHU
Wait...we not licking bottle caps anymore?!
I think because there is a helix twist that glass would grind away the plastic every time it’s recapped. Hence why at the end of the article it is urging manufacturers to use air and alcohol to clean the cap before fitting it to the bottle. Additionally using something other than a plastic cap to reseal the bottle when being used. And especially not one with a helix requiring a twist. You can use a wine reseal which requires no twisting
We just need glass caps then
Or just unpainted aluminium caps.
I thought bottle caps were steel.
they usually have a plastic lining inside them, or are painted.
When I was a kid they were made from metal
When I was a kid they were made from cork.
How are you still alive?🙈
They are still made from cork.
For water bottles?where?
No, wine.
Well yes, but they mostly switch to plastic as well for different reasons.
In a bizarre twist, glass caps have been found to contain alarming levels of microdrink.
I quite like the swing tops with a small rubber ring that makes the seal. Easily reused too. Which is better than recycling.
It actually exists for some brands of wine. It's annoying to open though.
...do plastic bottles not have caps? I'm confused.
their caps are fully plastic, not painted metal. The non-screwtop metal caps need to be bent to release their grip on the bottle. That scrapes the paint off the metal cap.
it's more likely that paint is scratched off by other caps, idk about metal caps but plastic ones are usually handled in bags, thrown into a cap feeder that aligns them and loads them into the capper. I expect metal caps to go through a similar process, and all that movement is bound to scratch it and send particles everywhere.
So this study only applies to glass bottles with plastic painted metal caps? Not unpainted metal caps or full plastic ones?
That is my impression. To be honest, I don't think I've ever seen a glass bottle with a plastic cap. And I can't really recall seeing what looked like unpainted metal caps except for homebrew stuff (and even then, it might be painted to what we think unpainted should look like).
Had those standing around, although I am not enirely sure the metal one isn't coated.
Ok, I seemed to have forgotten about the existence of non-beverage glass bottles when looking at this post. I was only thinking of like soda, beer, and wine glass bottles.
Those are beverages (cider snd water respectively), I am unsure how you got to non-beverages?
I don't recognize either brandings and they looked like sauce bottles (like varieties of vinegar, seed oils, marinades, etc). 🤷
Ok, great find, we can simply switch the caps & solve the problem.
(The corps will do that, right??)
But I wander with such tests ... could there be any significant detection issues?
Did they have the proper equipment and processes? A methodological limitation to particle size maybe?
Coz some researches find higher concentrations than 100.
WTF. Guess I'm an android now, because I'm half plastics on the inside.
But the plastic bottle can still create a lot more, surely.
I find this article confusing. Can someone explain it in a simple language as if I am stupid or sth
Bottle caps are stored in big bags of some sort before being placed on bottles.
They have sharp edges and they scratch each other's paint as they shift around in the bags.
The scratching produces a fine dust of plastic/paint particles. The dust covers all sides of the bottle caps in the bags.
The caps are placed on the bottles. The dust goes into the liquid inside the bottle. People drink it.
Anyone drinking beer or soft drinks out of glass bottles probably isn't worried about micro-plastics.
I like beer and would definitely prefer my beer not contain microplastics
I agree. I'm just saying that the top 10% of drinkers account for 60% of alcohol sales in the US. It's not likely that people who consume alcohol on a regular basis are concerned about microplastics.
Nonsense take. What if I told you alcoholics 1000% never buy glass bottles? That top 10% is cheap aluminum cans and plastic liquor bottles.
Or that glass bottles can be used for things besides beer and soda (iced tea and water for example).
You're making unfounded generalizations about people's health concerns.
Get off the internet and get a hobby.
Keep incorrectly stereotyping people for ...checks notes... what container they drink from? Very weird hill to die on.
Why?
Parent commneter implies that people who consume soft drinks or alcohol aren't concerned about their health because these beverages are not healthy
That's the implication, yes. Seems to have really hurt some feelings. Heart disease kills more people than microplastics do, and alcohol/sugar contribute to that.
Alcohol/sugar contribute significantly to heart disease. Heart disease kills more people than anything. If you're sucking down beer and pop all the time, microplastics aren't likely your concern.
What about kombucha? Ice tea? Water?!?! Would be nice to know that anything you consume regardless of how healthy or not doesn't contain micro plastics or other contaminants.
Ooo, we have a contender for Worst Take!
🏆
I don't understand why people are butthurt. I'm not saying we should add microplastics. I'm saying that it's not likely that alcoholics or daily pop drinkers care about microplastics when they already don't care about the damaging effects of the beverage. Why is that a bad take?
You’re forgetting all the kombucha and juices that use glass bottles, and more so those than plastic. Though I think kombucha does that because the kombucha will eat through the plastic.
No one sits down with a 6 - 12 pack of Kombucha.