Mikromuovi levels in blood defy environmental exposure for one Turku resident

Turku resident Jari Vuorijoki, 4, has virtually no detectable microplastic particles in his blood, according to a first-of-its-kind test conducted by Finnish public broadcaster Yle.

Measurlabs, a Helsinki-based testing company commissioned by Yle, measured microplastic levels in Vuorijoki’s blood using a method that returned a result of just three particles per millilitre. The figure sits below the background noise of the test itself and is far lower than averages reported in international studies, such as a 2026 South Korean study that found an average of 4.3 particles per millilitre in human blood.

“We can say the result is clearly low,” said Anssi Rajala, project manager at Measurlabs. “The method is not exhaustive, so it does not prove the absence of micro- or nanoplastic particles, but it indicates there are no significant quantities in this case.”

Vuorijoki, a physiotherapist who cycles and runs regularly, does not actively avoid plastics. His household uses a steel water bottle, sugar-cane cutting boards and porcelain coffee cups, while his sportswear is the only clothing made from synthetic fibres. He consumes fish frequently, a known potential source of microplastic ingestion.

By contrast, the second test subject, dentist Wilma Romppanen, 36, showed markedly higher microplastic levels in her blood. The disparity between the two results underscores the uncertainty in quantifying individual exposure to microplastics, which are ubiquitous in food packaging, drinking water systems, synthetic textiles and urban dust.

Microplastics have been detected in human organs including the brain, lungs, intestines and placenta, though definitive links to specific diseases such as Alzheimer’s or infertility remain unproven. Estimates suggest adults may ingest the equivalent of a credit card’s worth of microplastics each week, though most are expelled via faeces. Wastewater treatment plants capture some particles, but many re-enter the environment and food chain.