Selenium in agriculture, food, and nutrition*
M. Sager
Austrian Agency for Health and Food Safety, Competence Centre for Elements, Spargelfeldstrasse 191, A-1226 Vienna, Austria
Abstract: In the case of Se, the concentration range between essentiality and toxicity for terrestric animals and humans is rather narrow, while aquatic organisms are much less affected, and no essentiality to green plants and aquatic macrophytes has been established yet. This review focuses on the situation in Europe, where Se levels are generally low. Apart from industrial and mining activities, the main Se sources are the burning of coal and selenite additions to animal feedstuffs. Reduction processes in sediments, soils, and feedstuffs to yield elemental Se act as sinks for available Se forms. In soils and crops, Se levels get enhanced from recycling of manure, dung, and sewage sludge, which is beneficial for Europe. New data from Austria have been added to the detailed discussions. In human nutrition, Se is supplied via pork, liver and kidneys, seafood, and cereals, but main sources as well as blood Se levels vary between different countries and nutritional habits. Food processing, like boiling, baking, or grilling, results in Se losses.
Keywords: selenium; selenium supplementation; metabolic pathways; trace analytical methods; food.
*Paper based on a presentation at the 2nd International Symposium on Trace Elements in Food (TEF-2), Brussels, Belgium, 7-8 October 2004. Other presentations are published in this issue, pp. 65-143.