Bioplastics Leach Heavy Metals When You Digest Them

"Bio-based" plastics break down in your gut and release heavy metals into your bloodstream. So much for the safer alternative.

What Happens When You Swallow Bioplastic

A 2026 study in Environ Pollut tested three common bioplastics (PLA, PHB, and PHBV) using a model that simulates human digestion. They measured which metals get released as these microplastics move through your stomach and intestines.

The results: cadmium, cobalt, and antimony leached out at levels that pose non-carcinogenic health risks for both adults and children.

Cancer Risk From Chromium

Chromium released from PHB and PHBV bioplastics posed carcinogenic risk for both adults and children. The digestive process breaks down the plastic enough to free these metals, and your gut absorbs them into the bloodstream.

Each type of bioplastic behaved differently. They don't all release the same metals or the same amounts. But none of them were clean.

The "Green Plastic" Problem

Bioplastics are marketed as eco-friendly. They may biodegrade faster than petroleum-based plastic, but that breakdown happens inside your body too. And when it does, you get a dose of whatever metals were trapped in the material.

What You Can Do

Don't assume bioplastic is safe just because it's "plant-based." Use glass, stainless steel, or ceramic for food and drinks. And explore non-toxic kitchen alternatives to avoid microplastic exposure from any source.

Also see glass food containers for safer alternatives.

Source: Terán-Baamonde et al. (2026). Environ Pollut.