Are our bodies full of microplastics or not? There’s a way to resolve this debate, and scientists must hurry

Activists from the Ecological Observation and Wetlands Conservation and students protest about the impact of single-use plastic, Surabaya, Indonesia, 16 July 2025. Photograph: Juni Kriswanto/AFP/Getty Images

Are we being injured and killed by ubiquitous, teeny-tiny shards of toxic plastic? Or aren’t we? For many months, the Guardian has reported a series of worrying scientific results that our bodies are full of jagged microplastic particles that could be giving us everything from heart attacks to reproductive problems.

But on Tuesday, the Guardian revealed that a significant number of scientists think many of these studies showed no such thing. Or maybe they did. The methods are new and riddled with problems, so we can’t always reliably tell.