The standard provides graphite furnace atomic absorption spectrophotometry for the determination of lead and cadmium in soil. The detection limit for lead and cadmium is respectively 0.1mg/kg and 0.01mg/kg (calculated by 0.5g sample, digest and make the solvent to 50ml). Zeeman, Smith—Hieftie and D2 methods are used for background deduction. Trace lead and cadmium is tested directly in the solvent where there is such chemical modifier as diammonium phosphate and ammonium chloride. No interference is found.

Soil quality-Determination of lead, cadmium-Graphite furnace atomic absorption spectrophotometry (GB/T17141-1997)