Metabolism and Excretion of Gallium Arsenide and Arsenic Oxides by Hamsters following

9, 730-737. The increasing use of gallium arsenide (GaAs) in the electronics industry has pro-duced the need for pharmacokinetic and toxicologic data on GaAs. The disposition in male Syrian golden hamsters (n- 4) following intratracheal instillation of GaAs (mean volume diam-eter 5.8 (im), arsenic(III) oxide (arsenite), and arsenic(V) oxide (arsenate) at a dose of 5 mg/kg body weight was examined. Blood, kidney, liver, and lung samples were collected at 1,2, and 4 days after administration. Excreta were collected daily. Urinary metabolite profiles were deter-mined after separation on a mixed anion-cation-exchange column. Total As content was ana-lyzed by direct hydride flame atomic absorption spectrophotometry after digestion. Arsenic blood levels after GaAs, arsenite, and arsenate administration were 0.185 ± 0.041, 0.596 ± 0.117, and 0.310 ± 0.045 ppm, respectively, after Day 1. Arsenic blood levels after GaAs administration increased to 0.279 ± 0.021 ppm on Day 2 indicating continued absorption while levels decreased for the arsenite and arsenate groups. At Day 1 the liver contained 0.565 ± 0.036, 2.62 ± 0.26, and 0.579 ± 0.144 % of the arsenic dose of GaAs, arsenite, and arsenate, respectively. The arsenite and arsenate were rapidly excreted in the urine with almost half the dose appearing after 4 days; in contrast, only about 5 % of the GaAs was found at the corresponding time. Tota