FLOW-INJECTION ATOMIC-ABSORPTION DETERMINATION OF PB USING ETHYLATIONAND IN-SITU CONCENTRATION IN A GRAPHITE TUBE

An automated method is described for the atomic absorption determinati on of sub-ppb concentrations of Pb using an automated flow injection t echnique. Pb is converted to the volatile Pb(C2H5)4 by reaction with N aB(C2H5)4 and subsequently collected in a graphite furnace at 300-degr ees-C. An absolute detection limit of 12 pg is achieved corresponding to a relative concentration LOD of 2 pg/mL using a 5-mL sample loop. R esults for the determination of Pb in biological tissues and natural w ater certified reference materials are reported.