Which is the healthier choice over the long term: boiled tap water or bottled water?
Looking at five samples each of three common bottled water brands, researchers found particle levels ranged from 110,000 to 400,000 microscopic plastic pieces per liter, averaging at around 240,000 according to a study in Proceedings of the National Academy of Sciences in 2024.
These tiny nanoplastics can enter the bloodstream through intestinal or lung cells, travel to organs such as the heart and brain, and even cross the placenta into a fetus.
Tap water isn't free from plastic either. Research analyzing 159 tap water samples from 14 countries found microplastics or nanoplastics in 129 of them — an 81.1% detection rate.
While the full health impact of microplastics is still being studied, evidence shows they can reduce absorption of micronutrients, trigger intestinal issues like diarrhea and cramps, and cause inflammation by irritating tissue.
Here's the good news: boiling water can significantly reduce microplastic intake. Letting boiled water sit and using a filter can help even more.
Besides drinking water, microplastics also enter our bodies through other common sources:
Food containers, especially from takeout meals.
Hot drinks like coffee or tea served in plastic cups or with plastic straws.
Seafood such as fish and shellfish, which can accumulate microplastics from polluted waters.