DETERMINATION OF TRACE-ELEMENTS IN ORGANIC SPECIMENS BY ENERGY-DISPERSIVE X-RAY-FLUORESCENCE USING A FUNDAMENTAL PARAMETERS METHOD

A rapid method for the simultaneous determination of trace elements in milk powder by energy-dispersive x-ray fluorescence has been developed. The measurement system consists of an Si(Li) detector, an x-ray tube coupled with zirconium as a secondary target excited source and a personal computer. Milk powder was analysed as pressed pellets and irradiated for 1000 s. Concentrations were determined by a fundamental parameters method. The detection limits are close to 1 ppm for most of the trace elements. The accuracy of the method was ascertained by analysing standard reference materials from the International Atomic Energy Agency. Good agreement was found between the certified and experimental values. Potential areas of applicability of the method are indicated.