Do plastic water bottles leach hormone-disrupting chemicals into drinking water?

What's actually in it

Most bottled water comes in PET plastic (polyethylene terephthalate). PET is considered food-safe by regulators, but that doesn't mean nothing leaches out. Chemicals called endocrine disruptors can mimic or block hormones in your body, even at very low levels. Common ones include bisphenols (like BPA and its replacements), phthalates, and nonylphenol.

Glass bottles exist as an alternative, but they cost more and break easily. Most people grab plastic off the shelf without thinking twice.

What the research says

A 2026 study in Anal Chim Acta used high-resolution mass spectrometry to test bottled water for multiple classes of endocrine disruptors at once. The researchers looked at how three factors affected contamination: the bottle material (plastic vs. glass), the water source (spring vs. purified), and the retail price.

Plastic bottles released more endocrine-disrupting chemicals than glass bottles. The bottle material had the biggest effect on contamination levels. Water source and price mattered less than you'd expect. A pricey brand in plastic still leached more than a cheap brand in glass.

Heat speeds things up. If a plastic bottle sits in a hot car or in direct sunlight, the leaching rate climbs. The chemicals move from the plastic into the water faster at higher temperatures.

These chemicals don't need to be present in large amounts to cause problems. Endocrine disruptors can affect your body at parts-per-trillion levels. That's why researchers are pushing for more sensitive testing methods, like the one used in this study.

If you drink bottled water regularly, glass or stainless steel bottles are the simplest way to cut your exposure. And never leave plastic water bottles in a hot car.