Anvisa issues warnings over borax use in homemade slime

The Brazilian Health Regulatory Agency (Anvisa) has updated its list of prohibited substances in cosmetics and personal hygiene products, including boric acid, boric oxide, and various borates such as borax. This regulatory change, RDC 1.030/2026, aligns with Mercosul rules and international standards due to accumulated toxicological evidence regarding reproductive and developmental risks.

While borax is authorized for uses in fertilizers, cleaning products, and medicines, its use as an activator for homemade slime is not a regulated purpose. The Brazilian Society of Pediatrics warns that the manipulation of chemicals to produce slime is potentially dangerous and recommends that children avoid handling boron compounds.

Medical experts note that while skin absorption of boron derivatives is relatively limited during brief, occasional contact, risks increase significantly with frequent or prolonged exposure, high concentrations, or if the child has skin conditions such as dermatitis, fissures, or burns.