Trace element risk assessment: essentiality vs. toxicity.

Risk assessment of essential trace elements examines high intakes resulting in toxicity and low intakes resulting in nutritional deficiencies. This paper analyzes the risk assessments carried out by several U.S. governmental and private organizations for eight essential trace elements: chromium, copper, iodine, iron, manganese, molybdenum, selenium, and zinc. The compatibility of the toxicity values with the nutritionally essential values is examined, in light of recently derived values, termed Dietary Reference Intakes, set by the U.S. Food and Nutrition Board of the Institute of Medicine. The results show that although there are differences in the values set by the different organizations, increased coordination has resulted in values that are more compatible than revealed in past evaluations.