Summary - Al
Aluminium is the third most abundant element in the earth's crust and is therefore a natural component of drinking water and foodstuffs and is a component of many manufactured materials. Exposure of humans to Al is mainly from food, water, airborne dust, antiperspirants, immunizations, allergy injections and antacids (1). Food additives provide a significant percentage of the daily intake. Aluminum is used as a direct food additive- as a firming agent, carrier, colouring agent, anti caking agent, buffer, neutralizing agent, dough strenghtener, emulsifying agent, stabilizer, thickener, leavening agent, curing agent and texturizer. These additives are used in milk, processed cheese, yogurt, preserves, jams and jellies, baking soda, sugars, cereals, flours, grains and powdered or crystalline desert products.
Table 1. Allowed Al-containing additives for use in foodstuffs by the European Parliament and Council Directives (Directives 94/36/EC, 95/2/EC, 96/85/EC, 98/72/EC and 2001/5/EC http://ec.europa.eu/food/fs/sfp/flav_index_en.html)
- Aluminum metal (E 173) is authorized for the external coating of sugar confectionary
and for the decoration of cakes and pastries.
- E520 Aluminum sulfate, firming agent
- E521 Aluminum sodium sulfate, firming agent
- E522 Aluminum potassium sulfate, acidity regulator
- E523 Aluminum ammonium sulfate, acidity regulator
(Aluminum sulfates (E 520-523) are permitted to be used in egg white up to 30 mg/kg;
and candied, crystallized glacé fruit and vegetables, up to 200 mg/kg individually or in
combination, expressed as aluminum
- E541 Sodium aluminum phosphate, acidic is permitted to be used in fine bakery
wares (scones and sponge wares only) up to 1 g/kg expressed as aluminum.
[Sodium aluminum phosphate, basic is not authorized in the EU as a food additive]
- E554 Sodium aluminum silicate, anticaking agent
- E555 Potassium aluminum silicate, anticaking agent
- E556 Calcium aluminum silicate, anticaking agent
- E558 Bentonite (hydrated aluminum silicate), carrier in food colors, maximum 5%
- E559 Aluminum silicate (kaolin, anticaking agent)
- E554-E559 are permitted to be used in dried powdered foodstuffs (including sugars);
salt and its substitutes; sliced or grated hard, semi-hard and processed cheese and
sliced or grated cheese analogues and processed cheese analogues, up to 10 g/kg;
chewing gum; rice; sausages as a surface treatment only; seasonings up to 30 g/kg;
confectionery excluding chocolate as a surface treatment only; tin-greasing products
up to 30 g/kg
- E1452 Starch aluminum octenylsuccinate, permitted encapsulated in vitamin
preparations in food supplements in food supplements up to 35 g/kg
- FD&C Red 40 aluminum lake (E 129)
Food is unquestionably the main source of aluminium intake, whereby the source is considered either primary or secondary. The primary content is the natural content of food caused by uptake from the geologic surrounding during growth and is for all practical purposes unavoidable. The secondary content is the primary content plus any possible contamination from aluminium articles that come into contact with food and additives as well as veterinary drugs, fertilisers and the air. The joint FAO/WHO Expert Committee on Food Additives reduced the tolerable weekly intake value for aluminium to 1 mg/kg body weight/week.
In a recent study (2), aluminium concentrations in over 1400 samples of food and beverages was analysed. Al concentration ranged between 0.4 and 737 mg/kg or mg/l. Cocoa powder and chocolate count amongst those foods that showed the highest aluminium concentrations found in this study. High levels are naturally present in tea leaves, along with cereal crops and cereal based foods such as breads and certain cakes and pastries.
Additional contamination can occur through articles (aluminium trays, aluminium baking trays and aluminium cans for beverages) that come into contact with food and that contain aluminium since aluminium is unstable in the presence of acids and bases if the protective transparent oxide film is damaged, e.g. by fine fissures.
According to the results of in this study, the aluminium contents of foods in aluminium packaging (beverages, cakes and various ready-to-serve meals) are so small that one must draw the conclusion that migration of aluminium from the packaging into the food can be ignored.
Al is known to induce a broad range of physiological, biochemical and behavioural dysfunctions in laboratory animals and humans (3).