| Popis: |
The consumption of wheat bran, whole-wheat grains and other whole-wheat products has grown in recent years in Brazil. These foods are considered more nutritious than the refined ones and have been associated with a reduced risk of some major chronic diseases. On the other hand, other research, carried out in Brazil, has found different groups of fungi toxins, called mycotoxins, contaminating these wheat products. Among these mycotoxins, are the aflatoxins, a group of genotoxic and carcinogenic compounds produced by Aspergillus spp. This study aimed to determine the levels of aflatoxins B1, B2, G1 and G2 in samples of whole-wheat grains and derivatives, intended for human consumption, marketed in the metropolitan region of Rio de Janeiro, Brazil. One hundred and eight samples of whole-wheat grains (n=35), wheat bran (n=32), whole-wheat flour (n=26) and refined wheat flour (n=15) marketed in hypermarkets, supermarkets and health food stores were analyzed by High Performance Liquid Chromatography with fluorescence detection (HPLC-FL). Thirty-three samples (30.6%) were positive for at least one aflatoxin and the B1 form had the highest prevalence in the samples. The overall average was 0.69 µg/kg and the contamination was the highest in the grain samples, followed by bran, whole-flour and refined flour. Just one sample showed total aflatoxins levels (B1+B2+G1+G2) higher than the limit established by Brazilian legislation (5 µg/kg). The levels found in this study indicated that the presence of aflatoxins in wheat and wheat products consumed in Rio de Janeiro, Brazil, are not a hazard for public health. |
