Assessing the bio-availability of Aluminium and Manganese in food products

Abstract

The toxicity of a substance is largely defined by its bio-availability. Therefore, the FSA has investigated the bioavailability of aluminium and manganese depends on the foodstuffs they are in, since a food’s characteristics affects how it breaks down in the gut and how the chemicals are released. In order to determine the daily intake of a chemical compound, it is essential to understand the percentage of the aluminium that is accessible for uptake, apart from the amount of aluminium in a product. The percentage bioaccessibility differed between products for both aluminium and manganese, suggesting that for each element the matrix effect (e.g. pH, and facilitating substances) differed among food products. The study reports that with increasing concentrations of aluminium, there is a saturation level where no more absorption occurs. Substances such as citrate act as a facilitator for aluminium absorption. The absorption of manganese is consistently at very low levels, suggesting that its overall absorption is very low. Other findings are, loose leaf tea showed a higher aluminium bioavailability than instant tea (0.05% vs 0.46%). Peas, beetroot, spinach and raisins reported a manganese bioavailability of 0.2 to1.0%, However, these products all contain low levels of manganese.