Aluminium in infant cereal: total concentration and bioaccessible fraction

Enriched food with specific nutrients such as infant cereals has become an excellent alternative as a complementary food for children. They are usually produced from corn, rice, wheat and oat flour. This requires consideration of the correct nutrient balance (proteins, carbohydrates, fats, minerals and vitamins), quality of essential fatty acids, occurrence of potentially harmful substances and the correct introduction of potential allergic ingredients. High levels of inorganic contaminants, such as aluminium (Al), can be found in these foods, which could represent a risk to health. In terms of toxicology, Al can act as a potent neurotoxin that causes impaired mental development in the long term exposure and can also be incorporated into infant bones, resulting in a weakened bone structure. Infants have been reported to be highly vulnerable to Al exposure and have a narrow tolerance to this non-essential element. Therefore, based on the relevant concern about Al toxicity, the objectives of this work were: to determine the levels of Al in 9 different samples of infant cereals (rice flour composition) from 3 distinct batches and 3 different brands commercialized in Brazil, and study the bioaccessible fraction of Al. Total Al was determined by acid-microwave digestion and ICP OES, and an in vitro digestion method was employed to evaluate the bioaccessibility. Rice flour composition presented mean concentrations for total Al of 1.3 mg kg-1 for brand A, 3.8 mg kg-1 for brand B and 3.2 mg kg-1 for brand C. Regarding Al bioaccessible fraction, mean values of 8.1%, 6.7% and 6.2% were found for brand A, B and C, respectively. In general, despite high obtained values of total Al in cereal sample, its bioaccessible fraction is relatively low; moreover, further studies must be developed regarding Al bioaccessibility considering the ingredients contribution of this food matrix for infants’ diet.