[LUM#6] Citizens and scientists
A participatory science project to measure air quality: when researchers and citizens join forces, science advances... and everyone wins.
September 2015: a collective of 23 associations in favor of streetcar line 5 knocked on the door of the world of research. This group of hundreds of citizens is asking a question: is the air cleaner on streetcar tracks than along roads? One of its members has heard of an English study on fine particles deposited on plants near roads. This is a new method of measuring air quality, not yet widely used, but apparently reliable. The equipment used was that of Pierre Camps, from the Geosciences laboratory. Without hesitation, the associations decided to call on the researcher.
Shared knowledge
" Air quality is not my usual field of research ," says this specialist in rock magnetism. In the end, he let himself be tempted by the adventure. But for this unfunded study, he needed the means. So he asked some sixty citizens to collaborate directly. An emblematic example of participatory science is born. In January 2016, each volunteer is individually trained... And the work can begin. For six months, volunteers gather leaves from eleagnus trees, holm oaks, ivy and oleanders. The trees and shrubs are clearly identified for each picker, for example near his or her work or in his or her garden. Samples pour into the lab from an area stretching from Cournonterral to Clapiers and Montferrier, via Montpellier. The scientists then analyze the leaves. But they want to be sure that the pickers respect the protocol. So they duplicated the measurements on their own, in a few sectors. Verdict: the leaves were collected in an impeccable manner. Everyone played the game perfectly.
" We obtained a thousand pieces of data in six months. We couldn't have done it without the volunteers. For a researcher, this cooperation is ideal ", says Pierre Camps. A great achievement, but also a sharing of knowledge. " We researchers get out of our own walls. It's very enriching. I've learned a lot from discussions with the volunteers, who are very well-informed and cultured, about fine particles and botany, for example. There's a lot of knowledge in society, and the researcher has a personal interest in the knowledge shared .
Constructive responses
What were the results of the study? There are not necessarily fewer fine particles in the vicinity of the streetcar(La Marseillaise, 2016). Just the opposite of what the public expected! The reason is undoubtedly the abrasion of the streetcar's wheels, brakes and rails. " A streetcar wheel loses 10% of its size over its lifetime. The wheel literally turns to dust; you can breathe it in, " explains Patrick Nicol, volunteer coordinator. The citizens involved were not disappointed, however... Above all, they wanted constructive answers.
On the theme of air quality, participatory science continues. A project is starting up in Saint-Aunès to study the impact of the doubling of the A9 motorway and the effect of plant walls. Although this type of collaboration with citizens is still rare in the earth sciences, Pierre Camps has plans. In his laboratory, he is helping to set up a new "geophysics and society" group. To continue enriching each other.
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