People all over France woke up Monday to a lot of green, specifically in the water: 12 rivers had been dyed the bright color, in a move that environmentalists hope will bring awareness to pollution in the country. 

Le Figaro reports that the environmentalists struck ahead of a conference in Paris, and that up to 12 departments, or regions, of France were hit with dye. 

The environmentalists, who were also protesting a diminishing amount of state money devoted to environmental causes, claim that the dye, a type of fluorescein, is harmless. (This may not be true.)

Harmless or not, the dye is different than what Chicago uses to famously turn the Chicago River green every St. Patrick’s Day. The formula for Chicago’s dye is top secret.