Microplastics come from plastic.

Stay with me. Microplastics come from plastic, so why are there headlines going around about finding them in beverages in glass bottles?

And specifically more microplastics in glass bottles compared to plastic. Like, a lot more. You would think that you could  go for the glass-bottled soda to avoid having more microplastics in your life, but no, apparently the darn things are everywhere.

But while this is a real  finding scientists have made, there are plenty of caveats,  and it’s too early to panic. So let’s unpack this scary headline. [♪INTRO] Microplastics are, as the name  suggests, tiny pieces of plastic. The biggest ones are about five millimeters, which is roughly the size of a standard lego stud.

The smallest ones are just one nanometer across. That’s about a hundred thousand times smaller than the width of a human hair. Several studies have found  microplastics inside human bodies.

They’re in our blood, our  lungs, and even our brains, although those studies can have their own flaws. One of the most common ways that microplastics get into our bodies is through our food and drink. We don’t know too much about whether or how these tiny particles can  actually affect our health.

But it’s important to find out  as much as we can about what and how much people are consuming so we can start to make those connections. In 2025, a group of French scientists measured the amount of microplastics in a bunch  of different drinks, including water, beer, wine, and soft  drinks such as soda and lemonade. This is the European version of  lemonade, so it’s fizzy, by the way.

The scientists also studied  how the packaging might affect the amount of microplastics in a drink. They tested beverages in glass  bottles, plastic bottles, cans, and a couple of types of big plastic jugs. Overall, the amount of microplastics  in each drink varied pretty widely.

But both the wine and the water  they tested contained notably few microplastic particles, regardless of  the type of container they came in. But even with the variability,  one odd trend stood out. With the exception of wine,  most drinks contained more microplastics when they were  packaged in glass bottles than when they were in  plastic bottles.

Weird, right? The amount of extra plastic depended on the drink. Water in glass bottles contained almost three times more microplastics than  water in plastic bottles.

But lemonade in glass bottles had more than 70 times more microplastics  than it did in plastic bottles. That’s… kind of bizarre. After all, they’re microPLAStics,  not microGLASStics.

So where were all these  extra particles coming from? We’ll answer that question after we keep the lights on with this quick ad break. Thanks to Manta Sleep for  supporting this SciShow video!

Manta Sleep makes sleep  masks and sleep accessories so you have the energy to live your best life. To get 15% off their products, you can head to the link in the description. Instead of fighting the afternoon slump when you feel low on energy,  focus, strength, and clarity, you can lean in and refocus after a nice nap.

You can nap even when the sun’s out thanks to their adjustable silk sleep mask or any one of their selection of sleep masks and accessories. For 15% off your Manta Sleep masks and accessories and a free holiday recharge kit, check out the link in the  description and use the code SCISHOW. To track down the source of  the unexpected microplastics, the researchers collected as many  of the particles as they could from the glass-bottled drinks.  And they spotted some clues: Most of the particles were the same color and composition as the paint  on the metal bottlecaps.

They also found scratches on the  outsides of the caps themselves, along with tiny pieces of paint  on the insides of the caps. The scientists thought the caps  might scratch each other if they were stored all jumbled together  before going onto the bottles. Taken together, this means that the caps are the most likely culprit behind  the mystery microplastics – and yes, in this case paint counts as plastic.

This could also explain why the wine they tested didn’t contain many microplastics. Wine bottles usually have corks, not caps. So there’s no paint to flake off.

The researchers also investigated ways to limit the amount of microplastics  the caps shed into drinks. Blowing air onto the caps and  rinsing them with water and ethanol reduced the number of  microplastic particles that found their way into bottled water, but  it didn’t eliminate them entirely. Even though the study pointed to a  probable source of microplastics, it still has some limits.

For one  thing, the scientists only tested a handful of brands for each type of drink. And they only tested brands  that were available in France. The team tested six samples of each combination of drink and container.

But each set of samples came from the same batch of drinks prepared by the manufacturer. This makes it tough to know for sure if the results would be the same in a different batch. Which, look.

It’s easy to make  fun of small sample sizes, but somebody had to dump out  a load of drinks by hand, filter them, and run the  results through an instrument over and over again – it was a  pretty labor-intensive thing! They also only looked at larger microplastics — ones bigger than twenty microns across. That’s about a fifth as wide  as a strand of human hair.

The instruments they used couldn’t  pick out smaller particles. So we don’t know if there’s  a difference in how many of these smaller particles end up  in each drink or bottle type. It’s also hard to compare different studies on microplastics to one another.

There are some papers that back up this study. A few have found that caps are a  source of microplastics in drinks. And some have found microplastic contents pretty similar to the amounts in this paper.

But some other studies report wildly different amounts of microplastics in drinks. And there could be a whole bunch  of different reasons for that. It could be due to the scientific  techniques the researchers were using, the types and sizes of the  microplastics they were looking for, the kinds of drinks they studied,  and even where the study took place.

So with all that in mind, what do we do about it? The short answer is… we don’t know. You don’t necessarily have to stop  drinking out of glass bottles.

Microplastics were present in nearly all the drinks they tested in this study. So switching to plastic bottles or cans won’t completely cut plastic out of your diet. And again, different studies have found different amounts of microplastics in each kind of drink.

If you wanted to be extra cautious, you could avoid drinking from  bottles with painted caps. And if you’re a beverage manufacturer and you happen to be watching this… do those caps need paint, really? But even then, we just don’t  know if it actually matters.

We simply don’t know what amount of microplastics it’s safe to consume. The dose makes the poison, as  they say, but we don’t have enough information to know if or  when microplastics turn toxic. You probably intuitively  don’t want to eat plastic, and I’m with you on that one.

Research like this is starting to help build up that body of data, but we don’t have it yet. Without further studies, it’s  tough to make any concrete recommendations to help you  make an informed decision. So support your local toxicologist,  and we’ll get there eventually. [♪OUTRO]