An urban microbiome project will be conducted in Laval

A large-scale sampling campaign will be conducted in Laval over the next two years to provide a portrait of all the microorganisms present in urban environments and their genetic material.

It is hoped that the data collected on this “urban microbiome” will help identify developments that promote microbial biodiversity and best contribute to overall health, it was stated in a press release.

“What interests us when we examine the microbiome is understanding who is there, who does what, and what their function is in the environment,” explained project leader Professor Philippe Constant of the French National Institute for Scientific Research. “But also, the interaction with its environment, including humans. So it’s a really important dynamic because the microbiome is the basis of all our living systems on Earth.”

The aim of the project will therefore be “to understand a little how humans influence this balance in order to try to restore some of the damage we have done,” said Professor Constant.

“In urban environments, there are more microorganisms involved in greenhouse gas emissions,” he explained. “In a city, the microbiome tends to become homogeneous, so we lose the heterogeneity of life. But when you walk in a forest, every centimeter of soil has great diversity.”

Green infrastructure helps restore this diversity, which is becoming a little too homogeneous in urban areas, said Professor Constant.

Around 100 Laval residents will participate in the project from July 1, 2025, to June 30, 2027. Their mission will be to take samples from their environment, both indoors and outdoors, to better understand the microorganisms that live there, but also on their own skin.

The urban microbiome is composed of plant species, bacteria, and fungi present in urban environments, whether in the air, soil, water, buildings, public transportation, or even on the surfaces we touch daily. Each city thus has a unique microbial signature, influenced by its climate, geography, and human activities.

The project will take place in Carré Laval, which the municipality is presenting as a “future mixed-use eco-district dedicated to innovation and ecological and social transition.” The site will serve as a testing ground, with plans to directly apply the study’s findings to the design of green infrastructure.

“It’s a very degraded site and we need to restore it to health,” said Stéphanie Lord-Fontaine, vice-president of scientific affairs at Génome Québec, an organization that is funding this project to the tune of $150,000.

Genomics will be used to determine how “we can create our green spaces in a way that promotes overall health, that is, restore the site while ensuring a good quality environment, for humans, animals, and the microorganisms that make up the environmental microbial flora,” she added.

“Laval wants to stand out (…) and be sure to have the right way of creating green spaces in a city, since we know that poorly planned urban development obviously has an effect on the environment, but also on the health of human beings who live in the city,” said Lord-Fontaine.

When the urban microbiome goes haywire, she compared, “it’s a bit like when the human microbiome goes haywire: we don’t feel well.”

“This environmental data that we collect on our environment, on the organisms that live alongside us in our environments, will allow us to (…) create a living environment that will be conducive to overall health,” said Lord-Fontaine.

The benefits of green spaces for mental and physical health are well documented. These spaces also play a crucial role as reservoirs of biodiversity, but their precise impact on overall health remains poorly understood.

The research project therefore aims to fill this gap by studying the urban microbiome through environmental DNA (eDNA) “in order to guide the design of optimized green spaces by maximizing their benefits for human, animal and environmental health,” it was specified.

“We’re seeing environmental changes, and increasingly, we’re seeing impacts on humans,” said Professor Constant. “We know, for example, that a human exposed to green spaces tends to have greater microbial diversity on their skin or in their digestive system. These are links that have been demonstrated, but what we don’t yet fully understand is how we can modify the environment around us in urban settings to restore this loss of diversity in humans, but also in the environment.”

The project, Professor Constant concluded, will generate “evidence on how microbial diversity responds to urbanization.”

“It’s quite important because it will help many cities around the world make more informed decisions about their planning,” he said.

–This report by La Presse Canadienne was translated by CityNews