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NEN-EN 15621 specifies a method for the determination of the elements calcium, sodium, phosphorus, magnesium, potassium, sulphur, iron, zinc, copper, manganese and cobalt in animal feeding stuffs by inductively coupled plasma atomic emission spectrometry (ICP-AES) after pressure digestion. The method was fully statistically tested and evaluated for the elements calcium, sodium, phosphorus, magnesium, potassium, sulphur, iron, zinc, copper, manganese and cobalt within the following 11 animal feeds: 2 complete feeds (pig feed, sheep feed), 3 complementary feeds (3 mineral feeds), 1 mineral premixture, 3 feed materials (MgO, phosphate, CaCO3) and 2 feed additives (CuSO4, bentonite). For elements with a HORRAT values higher than 2 (e.g. potassium and sulphur, see Annex A), the method is more applicable as a screening method and not for confirmatory purposes. Other elements like molybdenum, lead, cadmium, arsenic were not fully statistically tested and evaluated within 11 animal feeding stuff samples because these elements did not occur in concentrations higher than the limit of quantification in most of these samples. A single laboratory validation is therefore necessary for the use of this multi element method for these elements. For the determination of extractable lead in minerals and feeds, containing phyllosilicates (e.g. kaolinite clay) wet digestion with nitric acid should be used. The method limit of quantification for each element is dependent on the sample matrix as well as on the instrument. The method is not applicable for determination of low concentrations of elements. A limit of quantification of 1 mg/kg should normally be obtained.