Brazil's water utilities have asked the courts for a temporary suspension, initially for 90 days, of the obligation to add fluoride to the public water supply. The request was filed by Aesbe, the Brazilian Association of State Sanitation Companies, which sees a risk of running out of fluosilicic acid in the coming months, according to a Folha de S.Paulo report published on Wednesday (26). The cause was a supply halt by fertilizer maker Mosaic, hit by soaring sulfur prices amid the Middle East conflict and the closure of the Strait of Hormuz.
Fluosilicic acid is a byproduct of phosphate fertilizer production, a process that relies on sulfur as a raw material. As sulfur prices climbed, Mosaic stopped supplying the input to water companies. Folha reported that Aesbe is studying imports as an alternative. Water fluoridation has been mandatory in Brazil since a 1974 federal law (law 6.050), and any suspension requires a court order.
Aesbe's members include Sabesp (São Paulo), Cagece (Ceará), Cagepa (Paraíba), Cesan (Espírito Santo), Sanepar (Paraná) and BRK. What is confirmed so far is the court request and Mosaic's supply halt. It remains unclear how many systems would actually run out of the input, or how long a suspension might last if granted. The case was also reported by the newspapers O TEMPO and Jornal de Brasília.
Impact depends on duration
From an oral health standpoint, the effect would be gradual. According to Thiago Lucena, a dentist with a master's degree in dentistry from the Federal University of Rio de Janeiro (UFRJ), fluoride dissolved in tap water protects teeth against acids produced by bacteria and helps remineralize enamel. The association presented no study quantifying the expected rise in cavities; the concern grows with the length of time the population goes without fluoridation.
"A temporary suspension of fluoridation does not mean people will develop cavities immediately, but it removes an important layer of collective protection," Lucena said.
The most exposed groups are children, the elderly and people in situations of socioeconomic vulnerability, for whom fluoridated tap water is often the main source of regular contact with the mineral. Until courts decide and while utility stocks last, the practical advice remains the usual one: brush teeth at least twice a day, a habit that by itself already prevents cavities and gum disease, as the report notes. If the suspension is confirmed in your city, paying closer attention to how children and older adults brush is the simplest protective step.