Improved wet digestion procedure for the analysis of total arsenic in biological samples by direct hydride atomic absorption spectrophotometry

Journal Article · · J. Anal. Toxicol.; (United States)

DOI:https://doi.org/10.1093/jat/8.3.118· OSTI ID:5563416

Webb, D R; Carter, D E

The presence of dimethylarsinic acid (DMAA) in biological samples can cause an underestimation of total arsenic content when analyzed relative to an inorganic arsenic standard by direct hydride flame atomic absorption spectrophotometry. An acid digestion procedure is described that quantitatively recovers DMAA as well as monomethylarsonic acid, inorganic arsenic(III), and arsenic(V) from aqueous and biological samples. Methylated arsenicals are converted to inorganic arsenic by wet digestion with HNO/sub 3/, H/sub 2/SO/sub 4/, and K/sub 2/Cr/sub 2/O/sub 7/ and subsequently reduced to arsenic(III) with NaI. Arsine is generated with NaBH/sub 4/ and converted to atomic arsenic following immediate introduction into a nitrogen-entrained air-hydrogen flame. This method produces a linear relationship to absorbance within a mass range of 50 to 300 ng arsenic/arsine reaction. A sensitivity of 2 ng arsenic and a detection limit of ng arsenic/arsine reaction were also obtained. Recovery of DMAA from water, urine, feces, or whole blood ranged from 92 to 105% with a coefficient of variation of 5 to 10%.

• Research Organization: Univ. of Arizona, Tucson
• OSTI ID: 5563416
• Journal Information: J. Anal. Toxicol.; (United States), Journal Name: J. Anal. Toxicol.; (United States) Vol. 8:3; ISSN JATOD
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400104* -- Spectral Procedures-- (-1987)
ABSORPTION SPECTROSCOPY
ARSENIC
ARSENIC COMPOUNDS
BIOLOGICAL MATERIALS
BIOLOGICAL WASTES
BLOOD
BODY FLUIDS
CHEMICAL ANALYSIS
ELEMENTS
FECES
HYDROGEN COMPOUNDS
MATERIALS
ORGANIC ARSENIC COMPOUNDS
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
QUANTITATIVE CHEMICAL ANALYSIS
SAMPLE PREPARATION
SAMPLING
SEMIMETALS
SPECTROSCOPY
URINE
WASTES
WATER