Fundação de Amparo à Pesquisa do Estado de São Paulo Nov 27 2024 A study by researchers working in Brazil shows that antimicrobial photodynamic therapy in which blue light targets annatto colorant is a feasible and effective option for treatment of halitosis in mouth-breathing children.  Annatto is an orange-reddish pigment derived from the seeds of  Bixa orellana  (achiote or urucum), a shrub native to tropical parts of the Americas.  Mouth breathing dries up the saliva, reducing its