After the mayor of a small French village banned the pesticide gysophate from land near homes and businesses in his municipality, the government took him to court—and sparked a movement as 20 other mayors across the western European country joined in barring the pesticide from their towns and cities.

Daniel Cueff, the mayor of Langouët, a village in France's northwest with around 600 residents, made the decision to ban the pesticide earlier in the year after the chemical began showing up in high levels in the urine of town residents.

As The New York Times reported:

Tests on the people of Langouët showed levels of glyphosate—one of the most widely used herbicides and the active ingredient in RoundUp—in their urine up to 30 times the recommended limit. It was especially high in children.

While French President Emanuel Macron promised in 2017 to ban glyphosate around the country by 2020, he later amended that promise to say it was impossible.

Cueff said he decided to act after seeing that, in his view, the national government wasn't going to do enough for the people of his village.

"Isn't the mayor of a village called on to fill in for the state’s deficiencies?" said Cueff.

But the French government didn't react kindly to the mayor taking matters into his own hands, bringing Cueff to court where it argued he did not have the authority to enact such a ban. The judge struck down the village ordinance, as Reuters reported in August.

There's a inconsistency there, Cueff told the Times:

Mr. Cueff says he doesn't understand why, on the one hand, the state barred town governments in 2017 from using glyphosate, but still allowed its use on farms cheek by jowl with small towns. "This is a contradictory message," he said. "Here in Langouët there are no contradictory positions."

At least 40 municipalities have followed Cueff's lead. The mayor said that shows that change is coming.

"Twenty years ago we were a bit alone," said Cueff. "They thought we were exaggerating. Today it's the opposite. People come to me and ask if they can't do more."