Do you think glass bottles are the cleaner, safer option? Think again. A surprising new study by French government scientists has revealed that glass-bottled beverages may contain up to 50 times more microplastics than their plastic counterparts.
Researchers at France’s food safety agency (ANSES) tested a variety of drinks—lemonade, iced tea, soda, and beer—and found that glass bottles contained an average of 100 microplastic particles per liter. In comparison, plastic bottles had as few as 2 particles per liter.
So, where are the plastic particles in glass bottles coming from? Not the bottle itself—but from the paint on the bottle caps, says lead researcher and PhD student Iseline Chaib. “We expected the opposite result,” she told AFP. “But the particles matched the polymer composition of the painted caps.”
In terms of drinks, sparkling and flat water had the least contamination (as low as 1.6 particles/liter in plastic), while sweetened drinks like soda and lemonade bottled in glass showed much higher levels, up to 40 particles per liter.
Even more confusing, wine in capped glass bottles had almost no microplastics, while other alcohols showed far higher counts. Scientists admit they still don’t fully understand why.
The good news? ANSES found a simple trick to reduce contamination: blowing air on bottle caps and cleaning them with water and alcohol cut the plastic particles by as much as 60%.
Bottom line: Glass might not always mean cleaner. If you’re concerned about microplastics, pay attention to the packaging and consider giving the cap a quick wipe before you sip.
