Fumonisin B(1) (FB(1)) and fumonisin B(2) (FB(2)) are mycotoxins mainly produced by Fusarium verticillioides, and Fusarium proliferatum, fungi species most commonly isolated from maize. The natural occurrence of FB(1) and FB(2) in broa, typical Portuguese maize bread, was evaluated in 30 samples. Twenty five were found positive with levels ranging from 142 to 550 microg kg(-1). The limit established by the European regulations was exceeded by 27% of the samples. The tolerable daily intake for fumonisin B(1), and B(2), alone or in combination, for all of the analysed samples, was lower than 2 microg kg(-1) body weight per day established by the European Commission.