In this study, arsenic levels in blood urine and faeces samples collected from mice which were orally administered arsenic trioxide (As₂O₃) and sodium arsenate (Na₂HasO₄), were determined. The animals were divided into one control and two experimental groups. Arsenic trioxide and sodium arsenate were given in daily doses of 5 mg/kg orally with water to experimental groups. During the administrations, in 10, 20, 40, 60 and 90th days, blood, urine and faeces samples were collected. Arsenic levels in samples were established spectrophotometrically by silver diethyldithiocarbamate procedure at 540 nm.

In the group treated with arsenic trioxide, the arsenic levels in blood, urine and faeces reached the maximum levels at 40, 60 and 40th days respectively. On the other hand, in animals given sodium arsenate, the highest arsenic levels in blood, urine and faeces were determined at 60, 90 and 60th days respectively. When these groups were compared, the mean level of arsenic in blood was approximately equal in both groups. However in the group treated with arsenic trioxide, the mean levels of arsenic in urine and faeces were observed higher than the group treated with sodium arsenate.

In conclusion, it was observed that the arsenic levels in urine and faeces are the best indicators but the arsenic levels in blood were lower than those in urine and faeces in arsenic trioxide and sodium arsenate toxicosis.