Acta toxicológica argentina
versión On-line ISSN 1851-3743
NAVONI, Julio A; OLIVERA, Nancy M y VILLAAMIL LEPORI, Edda C. Arsenic quantitation by flow injection-hydride generation-atomicabsorption spectrometry (FI-HG-AAS) after l-cysteine derivatization: Validation and inter-methodological comparison using two reference techniques. Acta toxicol. argent. [online]. 2010, vol.18, n.2, pp. 29-38. ISSN 1851-3743.
The presence of arsenic (As) in drinking water is a public health concern in many regions of the world, including Argentina. Quantification of arsenic in drinking water and urine are used to assess exposure to this pollutant. This study aimed to validate a methodology for the quantification of As species [AsV + AsIII + acid monometilarsónico (MMA) + dimetilarsínico acid (DMA)] by flow injection-hydride generation-atomic absorption spectrometry (FI-HG-AAS), after derivatization with L-cysteine. The results were compared with those obtained using two methods of reference, hydride generation-atomic absorption spectrometry (HG-AAS) for water and urine samples, and high performance liquid chromatography-hydride generation-atomic absorption spectrometry (HPLC-HG-AAS) for urine samples. In addition, the selectivity of quantification by FI-HG-AAS in the presence of other chemical species of As, from fishery products intake, was evaluated through a biological assay. The As level found in water and urine samples, using the techniques of reference, showed a range from 6 to 176 μg/L and from 143 to 3312 μg/g creatinine, respectively. Pearson coefficients resulting from the comparison of data obtained by FI-HG-AAS with those achieved by the reference methods were r = 0.9976 and r = 0.9422 for water and urine, respectively. The results of the biological test showed a higher level of As, due to consumption of food fishery product, when urine samples were previously mineralized (HG-AAS), with consequent overestimation of the inorganic arsenic consumption. When these samples were analyzed by FI-HG-AAS this fact was not observed, and the values were comparable to baseline level prior to consumption. The results indicate that the proposed methodology is a valid alternative for assessing exposure to inorganic arsenic without the use of prolonged pre-treatment, resulting cheaper and faster, and avoiding the overestimation for measuring other arsenic species of low toxicology impact.
Palabras clave : Arsenic; L-cysteine; Hydride generation; Methodological validation.