DETERMINATION OF URINARY ARSENIC BY SOLVENT-EXTRACTION AND ELECTROTHERMAL ATOMIC-ABSORPTION SPECTROMETRY - A COMPARISON WITH DIRECTLY COUPLED HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY INDUCTIVELY-COUPLED PLASMA-MASS SPECTROMETRY

A modified method for the determination of arsenic in urine using solv ent extraction with toluene and ETAAS is described. The urine samples were acidified with HCl and reduced with KI followed by a stripping st ep from the organic solvent with a 1% HNO3 solution, Only inorganic, m ono- and dimethylated arsenic species, correlated with occupational ex posure, were determined while trimethylated species, such as arsenobet aine, arising from seafood consumption, were not extracted, The result s were compared with those obtained by HPLC-ICP-MS, A good agreement b etween the two different determinations was found and the solvent extr action method was considered suitable for a correct evaluation of occu pational exposure to inorganic arsenic.