Concerns Over Microplastics in Water Bottles Left in Heat

Worried about microplastics? You might want to reconsider drinking that bottle of water that’s been baking in your car for a while.

Research on microplastics has ramped up recently, as awareness of their prevalence and health risks grows. These tiny contaminants might contribute to health issues ranging from liver damage to inflammation, and it seems we keep finding new sources. Just when you think you’ve evaded one, another pops up. One such source, however, is relatively easy to avoid: the plastic water bottle that’s been sitting in your car for who knows how long.

A 2023 study looked at how different temperatures and UV light impact four common types of plastics often found in bottles and packaging. The findings revealed that regardless of the type, they all released significant amounts of microplastic particles into the water, with billions of these tiny bits detected during testing. Meanwhile, bottles stored in cooler conditions barely released any at all.

This isn’t an isolated observation. Back in 2014, researchers at the University of Florida found similar outcomes when studying 16 brands of bottled water kept at 158°F for a month, labeling it a dire scenario for anyone consuming that water.

As Lena Ma, the lead researcher, pointed out then, leaving bottled water in a “hot garage for weeks or in your car all day during the summer” isn’t advisable.

In general, heat and plastic just don’t play well together. A previous study featured in Food & Wine highlighted that hot beverages are a significant source of microplastics. For example, hot tea contained about 60 microplastic particles per liter, while hot coffee had around 43. In contrast, iced versions showed much lower counts.

However, if you find yourself with that day-old bottle and no other options, don’t panic. Jaime Ross, a neuroscience professor, suggests it’s more about minimizing repeated exposure. It’s not only about ingesting microplastics; heat can also foster pathogen growth.

As for solutions, researchers from the 2022 study recommended that product labels should indicate the packaging materials and warn about the potential release of harmful substances like bisphenol A. In the meantime, taking matters into your own hands—like storing water in cool, dark places—and switching to reusable glass or metal bottles might be wise. And, don’t forget to follow some tips to lessen your microplastic exposure at home to avoid the ongoing battle against these contaminants.