Methodology of health risk assessment for urban gardens

Several cities in France are promoting the sustainable development of gardening activities in response to growing social demand for urban vegetable gardens (collective or family), and because of the ecosystem services provided by these activities: participation in a food transition towards a more sustainable system (local production, agro-ecological practices, social ties, landscapes) and in the circular economy. . In 2018, there were around a hundred garden sites in Paris, and in Toulouse the number of sites tripled between 2006 and 2016. But available urban space is scarce and frequently polluted especially when they are old and densely populated. However, certain pollutants are persistent in the environment: metallic elements (metals and metalloids), organic compounds including total hydrocarbons (TCHs), polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). It is therefore crucial for city managers who make urban vegetable garden sites available to citizens to have a methodology for assessing and managing potential environmental and health risks for users of these sites.

What's more, citizens are generally very attached to the collective or allotment (peri-)urban garden sites where they've been meeting and gardening for years; that's why when pollution is discovered users want to continue their gardening activities and ask the mayor to find solutions.

For example, studies carried out by the Direction régionale et interdépartementale de l'alimentation, de l'agriculture et de la forêt d'Ile-de-France (DRIAAF) in 2008 on the urban gardens of the city of Montreuil showed that the soil and plants were contaminated by metals (lead, cadmium, copper, mercury and zinc), with lead levels...