Selenium is an essential element for human health. Recent trials have shown that by applying just a few grams of selenium via selenium enriched fertilizer at the right time to crops, it is possible to produce bread that could restore the average dietary selenium intakes to recommended levels.
According to the UK Food Standards Agency, "Selenium plays an important role in our immune system's function, in thyroid hormone metabolism and in reproduction. It is also part of the body's antioxidant defence system, preventing damage to cells and tissues".
Selenium intakes in the UK, however, have fallen over the past 30 years. Martin Broadley, BAGELS Project Leader , explains, "This is mainly because we no longer import high-selenium wheat used for milling from North America. We now grow most (>80%) of our own milling wheat here in the UK, where soils are naturally low in selenium. So, whilst the amount of selenium we should consume (the Reference Nutrient Intake) is 60 µg/day for women and 75 µg/day for men, the average daily intake in the UK is estimated to be only 34 µg/day. Of this amount, at present, we obtain only 6 µg /day of selenium on average from bread."
BAGELS (Biofortification through Agronomy and Genotypes to Elevate Levels of Selenium) is a 'farm to fork' project (2005 to 2009) sponsored by Defra (Department for the Environment, Food and Rural Affairs) through the Sustainable Arable LINK Programme. Instigated to determine if selenium levels of UK-grown wheat could be increased safely by using selenium-containing fertilizers (i.e. agronomic biofortification), without causing harm to the environment, its partners span the entire food chain – from research bodies to manufacturers and retailers – and consist of The University of Nottingham, SCRI, The Institute of Food Research, The University of East Anglia, Rothamsted Research, Carr's Fertilisers, Marks and Spencer plc, Nickerson-Advanta Ltd, Velcourt Ltd and Yara (UK) Ltd.
The fate of the soil-applied selenium was monitored in the crop and soil in trials conducted at sites at The University of Nottingham, Rothamsted Research and Velcourt. Soils treated with selenium were analysed by Rothamsted Research, with results showing no residual build up of selenium that could pose an environmental risk. Analysis of the crop has revealed the distribution of the selenium with some remaining in the straw, but the majority moving into the grain. The selenium levels and chemical forms were analysed in grain and flour fractions and in bread products at The Institute of Food Research and The University of East Anglia, so that the fate of the selenium was determined all the way through the food chain.
Dr Martin Broadley is delighted with the results achieved by the project, commenting that, "The results confirm that the use of trace amounts of selenium-containing fertilizer to biofortify UK wheat could potentially restore daily intakes of selenium to recommended levels, which would be a tremendous achievement for the UK cereals industry".
