Desarrollo y optimización de una metodología para la determinación de metales y semimetales en cabello

Hair is an alternative biological matrix widely used in biomonitoring programs. It is used as a biomarker of chronic exposure to environmental contaminants and to evaluate pathologies related to the excess or shortage of certain substances. Hair is a complex matrix for the evaluation of toxics in low levels. This matrix is an analytic and pre-analytic challenge. In this work, the development and validation of a methodology for the determination of mercury (Hg), lead (Pb), arsenic (As) and manganese (Mn) by atomic absorption spectrometry is presented. The sample treatment was carried out by microwave assisted digestion. The determination of Hg was carried out using cold vapor (CV-AAS) and hydride generation (HG-AAS) was used for As. Mn and Pb were analyzed by electrothermal atomization (ET-AAS). The figures of merit evaluated were linear range, limits of quantification and detection, accuracy at three levels and veracity. The latter was evaluated using a hair reference material (No. 13 Human Hair, from the National Institute of Environmental Studies-NIES, Japan). The validation of this methodology is very useful for the study of exposure to these analytes, because of the simplicity of sample obtention.