Evaluation of laser induced breakdown spectrometry for the determination of Ba, Cd, Cr, Pb and Sb in toys

Abstract

The aim of this project is an evaluation of Laser Induced Breakdown Spectrometry (LIBS) for the determination of Cr, Ba, Cd, Sb and Pb in toys. There is a great distrust of some segments of the society that many commercial toys in the Brazilian market have toxic elements in their chemical composition. To monitor the toys, it is necessary a technique that became easier the sampling process, permitting in situ analysis to any samples. LIBS is a technique that presents unique characteristics for direct solid analysis allowing sampling and excitation of the formed species with a single laser. In spite of its promising features either in the academy and industry, LIBS is not yet well established when compared to the flame atomic absorption spectrometry (FAAS) and inductively coupled plasma emission spectrometry (ICPOES). Particularly, it was not still evaluated for quantitative and semi-quantitative analyses of toys. The experiments will be carried out in LIBS system constituted by a pulsed Nd:YAG laser (10 Hz, model Brilliant, Quantel, France) of 1064, 532 and 266 nm (maximum energies of 400, 200 and 100 mJ/pulse, respectively), a high resolution spectrometer Echelle mounting and an ICCD (model ESA 3000, LLA Instruments, Germany), and software ESAWIN. Commercial ablation chambers will be evaluated for analysis of samples with different geometries. If necessary, a new ablation chamber will be developed during the project. The results obtained by LIBS will be compared with those obtained by ICPOES and/or FAAS. It is expected, at the end of this project, to demonstrate that LIBS is an appropriate technique for the initial selection and/or a classification of samples that will be submitted to leaching tests recommended by the Brazilian government. In addition, it is expected to anticipate the realization of fast screening tests in a great number of samples, ideally with a field portable LIBS. (AU)