In a food supplement enforcement exercise carried out by the Food Standards Agency (FSA) with local authorities, 48 products from a variety of outlets were examined.
11 supplements were completely irradiated and 13 had an irradiated ingredient.
Although the FSA says that these findings should not give rise to health concerns, the issue again highlights the fact that irradiation is still not acceptable in the UK.
Irradiation, used to prolong the shelf life of food products and/or to reduce health hazards, is a physical treatment of food with high-energy, ionising radiation. It exposes food to electron beams, X-rays or gamma rays, and produces a similar effect to pasteurisation, cooking, or other forms of heat treatment, but with less effect on look and texture.
Although an accepted manufacturing process in the USA and approved for use since 1963 to control mould and insect infestation in wheat and to inhibit the growth of sprouts on potatoes, European consumers remain sceptical of the food safety aspect.
At the moment, the only foods that may be irradiated and sold freely across the EU are dried aromatic herbs, spices and vegetable seasonings. These must be irradiated in an approved EU facility, labelled 'irradiated' or 'treated with ionising radiation' and accompanied by full and correct documentation relating to the irradiation treatment.
Imported food, which has been irradiated outside the EU, must also comply with the same labelling and documentation rules. Again, dried aromatic herbs, spices and vegetable seasonings are the only foods that may be irradiated outside Member States of the EU and sold freely within the EU.
These must have been irradiated at a facility approved by the European Commission. There are currently five approved facilities outside the EU, three in South Africa, one in Turkey and one in Switzerland.
The FSA says that as yet, it is not known why or where these food supplements were irradiated or what dose was used. None of the supplements were labelled as being treated with ionising radiation.
Local authority enforcement officers visited the companies whose products were irradiated to check what systems they have in place to prevent irradiated products reaching the market.
Two companies were given formal cautions.
The announcement follows the recent removal of a food product in the UK due to the presence of an undeclared irradiated ingredient. Danish firm Ferrosan was forced to withdraw two batch codes of Imedeen Prime Renewal food supplements due to the undeclared presence of irradiated white tea extract.
The irradiated white tea extract, manufactured in China by the China National Chemical Construction Anhui Company, does not comply with the Food (Control of Irradiation) Regulations 1990.
The FSA enforcement exercise, carried out in 2003, followed up an Agency survey of 2002, which found evidence of irradiation in food supplements. Publication of the results was deferred pending enforcement action by local authorities.