The solution, which uses wheat flour matrix certified reference material, enables manufacturers to determine the amount and type of selenium in products in order for them to be safe for human consumption.

Selenium is scientifically recognised as offering a range of benefits from antioxidant defence to the maintenance of good thyroid function. Research also suggests a link between selenium deficiency and cancer.

However, the decline in imports of naturally selenium-rich wheat flour from Canada and the US and its replacement with locally grown wheat, which is naturally low in selenium, is causing selenium deficiency in Europe.

The uptake and assimilation of selenium by the human body depends on its chemical species and there is a fine line between beneficial and toxic levels.

"The availability of low concentration certified reference materials with specified levels of certain selenium species is a very welcome development," said Dr Cathal Connolly, senior applications chemist from Alltech, who has been seconded to LGC to gain in-depth knowledge of selenium speciation methodology in food.