The CitieS-Health project distributed 1000 strawberry plants in Barcelona to measure air pollution in collaboration with the Vigilantes del Aire initiative.
As strawberry leaves are biosensors that can collect pollutants, citizens put them in their balconies during a period of time, then sent the plants to a research laboratory and received an individual report about their exposition. This experiment helped to map and add evidence about air pollution in the city.
Here you can read the report: