A simplified method for the extraction of the metals Fe, Zn, Cu, Ni, Cd, Pb, Cr, Co and Mn from soils and sewage sludges

Abstract
The method described for digestion of soil samples with aqua regia is simple, flexible and safe to operate with large sample throughout. At least nine metals can be determined in the resulting solutions with errors of <5%. The results compare favourably with those from reflux aqua regia and averaged 88% of the certified total values for reference soils and 88% of those for reference sewage sludges.