TRACE-ELEMENTS IN FOOD REFERENCE MATERIALS - COMPOSITIONAL AND ANALYTICAL PERSPECTIVES

Selection criteria for production of food reference materials need to simultaneously consider realistic proximate matrix compositions, emerg ing trends for the nutritional and toxicological effects of less-empha sized trace elements (e.g., B, Li, Si, and V), chemical speciation (es pecially for As, Hg, Se, and Sn), and analyte certification requiremen ts from the analyst's point of view. For the most part, currently avai lable Certified Reference Materials (CRMs) do not meet many of these n eeds. Candidate CRMs with relevant concentrations of trace elements co uld be chosen from similar foods with different proximate compositions (e.g., fat content of milk products, meat, or soya flour). Explicit g uidance must accompany CRMs so that variations in measured trace eleme nt concentrations arising from procedural lapses and basis weight are avoided.