The Nordic countries have issued common nutrition recommendations since 1980. In connection with the 3rd revision, a joint working group of nutritionists and toxicologists assessed the toxicology of selected trace elements. Values for upper limits of intake were established for iron, zinc, iodine and selenium. The safety factors between the lowest intakes at which adverse effects had been reported and the suggested upper limits of intake were small. In the toxicological evaluation of upper safe intake levels of essential trace elements, interactions between trace elements as well as long-term exposure to moderately elevated trace element intakes have to be considered.