This test method is a validated procedure for the quantitative analysis of multiple metals and elements using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). This method enables accurate determination of both essential nutrients and potential contaminants in complex biological samples. This test method quantifies calcium, copper, iron, magnesium, manganese, phosphorus, phosphorus (as P2O5), potassium, potassium (as K2O), sodium, sulfur, and zinc.