A third of French brands resort to prohibited purification, Le Monde and Radio France report. Government source refuting any “health risk” Nestlé Waters revealed Monday that it had used banned ultraviolet treatments and activated carbon filters on some of its mineral waters.

Alma group, which produces around thirty brands of bottled water in France, has confirmed that it is the subject of “legal proceedings” relating “to old and isolated facts specific to certain production sites” Like Nestlé, Alma rules out any health risk for consumers.