Arsenic speciation of arsine-exposed blood samples by high-performance liquid chromatography-inductively coupled plasma mass Spectrometry and as-adduct, a possible indicator of AsH3 exposure

Arsine (AsH3)-exposed human blood samples were analyzed by high-performance liquid chromatography with inductively coupled plasma mass spectrometry (HPLC-ICP-MS) for arsenic speciation. After exposure of human blood samples to AsH3 vapor for 90 min at room temperature, partial hemolysis was observed. Plasma samples from these whole blood samples were prepared by centrifugation at 1600 x g for 10 min and analyzed by HPLC-ICP-MS. In addition to arsenite [As(III); degraded from AsH3], an unidentified arsenic species (As-adduct) was detected at a retention time of 1.1 min. Following ultrafiltration of the plasma samples using a molecular weight cut-off of 10 kDa, As-adduct was not detected in the filtrate. To clarify the origin of As-adduct, AsH3 was added to blank plasma and As(III) was added to both whole blood and hemolyzed blood. Although As(III) was detected in all samples, As-adduct was not detected. These results indicate that As-adduct was derived from erythrocytes during the process of hemolysis by AsH3 and further suggest that As(III) and plasma ingredients do not contribute to As-adduct production. Therefore, the presence of As-adduct in blood could represent an indicator of acute arsine poisoning.