Microplastics in Microbreweries

Contamination Where You’d Least Expect It

Perhaps you would expect microplastics in the ocean, maybe even in bottled water — but in your favorite small-batch craft beer? That might catch you off guard.

Recent testing shows microplastics are found in microbrews. In fact, a 2025 study found that 95% of U.S. beers — from national brands to neighborhood breweries — contained measurable plastic particles. The surprise isn’t in the beer itself, it’s in the water they use.

The Hidden Source Was Right in Their Face

Microbreweries typical pride themselves on sourcing local ingredients — fresh hops, clean malt, and pure water. But that “pure” water isn’t, well, "pure". Microplastics, defined as plastic fragments smaller than 5 millimeters all the way down to the nano scale, have now been detected in tap and groundwater almost everywhere on Earth! So no wonder that stuff made it into beer, and probably soda, and just about any liquid that used water that wasn't carefully filtered.

These plastics come from synthetic fabrics, packaging, tires, and even household plumbing. That's right, just doing your laundry, driving your car, or watering your lawn could be putting microplastics into the environment. And once released, they move invisibly through rivers, aquifers, and city pipes — right into the water used to cook, clean and even brew beer.

A brewer can do everything right and still start with contaminated water.

How Tiny Plastics Slip Through

Municipal treatment plants aren’t designed to stop particles this small. Even a good sediment or carbon filter only captures down to about one micron (blood cells are about 8 microns). Some microplastics measure a tenth of that or less (that's nano scale).

That’s why even carefully filtered brewing water can still carry microscopic plastic fragments. They survive boiling and fermentation, and they don’t evaporate away. They just get passed along, quietly into the finished product and then into you!

Why It Matters

I might lose half my readers with this next statement. The concern isn’t really about beer (or is it). If microplastics are turning up in handcrafted beverages made from local water, they’re probably everywhere else too — in coffee, soup, pasta water, baby formula. Anywhere tap water goes, they go. The concern is what those microplastics do once they are in our bodies.

Microplastics can carry chemical "hitchhikers" such as those nasty forever chemicals, phthalates, and heavy metals. Research indicates that these substances can indeed attach to microplastics and may contribute to various health issues, including oxidative stress, hormone disruption, and inflammation. (Science of The Total Environment.)

Microplastics themselves, apart from their ability to carry harmful chemicals, have been documented to cause various adverse effects, including: physical damage to marine organisms through ingestion, leading to internal injuries or blockages, accumulation in the food chain, potentially affecting larger organisms and humans who consume seafood.

Studies have shown that microplastics can provoke inflammatory responses in organisms, which may lead to chronic health issues. (10.1098/rspb.2016.0163)

An Opportunity for Brewers

For breweries that already emphasize sustainability, this is a chance to lead the way. Many breweries are now adding reverse osmosis (RO) systems to their filtration line and if done right, it doesn't be replumbing everything. It’s not just about purity; it’s about transparency. Showing that you care about what’s in your water speaks volumes about the care you put into what comes out of your taps at both the bar and the kitchen sink.

What You Can Do at Home

Microplastics don’t stop at the brewery door. They flow into homes, restaurants, and coffee shops too. A home reverse-osmosis system or high-grade whole-house filter can dramatically reduce exposure. Remember, they are not just in what you drink, but also in what you cook and wash with every day.

Bottom Line

Microplastics in microbreweries aren’t a scandal; they’re a signal. Even in places built around craft and care, contamination has become unavoidable.

But it’s not hopeless. The same technologies that protect water for brewing can protect it in your kitchen. It's time to act. Get clean water.