USEPA (United States Environmental Protection Agency) method study 7. Analyses for trace elements in water by atomic absorption spectroscopy (direct aspiration) and colorimetry. Final report

The report describes a study of ten elements: aluminum, arsenic, cadmium, chromium, copper, iron, lead, manganese, selenium and zinc, at trace levels in water. Six sample concentrates, each containing the ten trace elements, were sealed in glass ampuls, verified as homogeneous and stable over time, and provided to the analysts with instructions for sample preparation and analyses. Mean recovery, overall standard deviation, and single-analyst standard deviations were calculated for each element at each concentration and for the two water types.