This Is What Happens When 1,000 People Bury Their Underwear for Science

Soil health can now be assessed by an unconventional method: burying underwear.

Ecologists from the University of Zurich conducted a study published in the journal Plants, People, Planet, involving over 1,000 citizen scientists—half of them farmers—to evaluate soil vitality across Switzerland. Participants were provided with two pairs of clean underwear, 12 teabags, and materials for soil sampling. Instructions guided them to bury the underwear and teabags in designated locations for either 30 or 60 days before retrieving and submitting them for analysis.

The study measured soil activity based on the decomposition of the underwear and teabags. Results indicated that private gardens, rich in organic matter, exhibited the highest decomposition rates, with an average of 58% of the cotton underwear breaking down after two months. Lawns showed lower decomposition, averaging 40%, while fields and meadows fell in between. Land use and nutrient levels were key factors influencing decomposition rates.

Marcel van der Heijden, a co-leader of the study, emphasized the importance of biologically active soil for fertility, nutrient cycling, and ecosystem services. The researchers proposed the "underwear index" as an accessible and engaging tool for assessing soil health.

Following analysis, the decommissioned underwear was repurposed creatively, with some transformed into a dress, symbolizing the intersection of science and art.

The study highlights the potential of citizen science in environmental research and offers a novel approach to understanding soil ecosystems.