Volatile inorganic- and organo-arsenic chloride species were detected following hydride generation. Arsenic trichloride can be formed and sampled from the headspace of arsenate or arsenite solutions following simple acidification to 2–8 M HCl. Mono- and dimethylarsenic chloride species are formed during conventional hydride generation using sodium tetrahydroborate in a HCl medium. Increased HCl concentration in the sample solution promotes the formation of volatile chloride species in the hydride mixtures. The generated arsenic chloride species were characterized using electron impact ionization mass spectrometry.