A method for digestion of plastics from waste of electrical and electronic equipment (WEEE) was developed using the microwave-assisted wet digestion in single reaction chamber (MAWD-SRC). The determination of As, Cd, Co, Cr, Cu, Ni, Pb, Sb and Zn by inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectrometry (ICP OES) was carried out after sample digestion. Mercury was determined by flow-injection cold vapor generation coupled to inductively coupled plasma mass spectrometry (FI-CVG-ICP-MS). Results obtained using MAWD-SRC for sample preparation were compared with those obtained using microwave-assisted wet digestion (MAWD) at high pressure. Acid mixtures (HNO3 or HNO3 + HCl) were evaluated and feasibility for further inorganic contaminants determination by ICP-MS and ICP OES was demonstrated. Sample preparation by MAWD-SRC using HNO3 + HCl mixture resulted in better digestion efficiency in comparison to MAWD. In addition, lower limits of quantification were obtained using MAWD-SRC due to the higher sample mass that can be digested (500 mg). The combination of HNO3 and HCl for digestion showed to be crucial for quantitative recovery of some elements, as Cr and Sb. Agreement with certified values was better than 96%.

Elementos traço e majoritários foram determinados em mexilhão dourado (Limnoperna fortunei) coletados no canal São Gonçalo (Rio Grande-RS, Brasil). Digestão assistida por microondas em sistema fechado foi utilizada para decomposição das amostras com subsequente determinação elementar por técnicas espectrométricas. Os resultados mostraram que o tecido de mexilhão contém Ag, Al, As, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, Li, Mg, Mn, Mo, P, Pb, S, Sn, Sr, Ti, V e Zn, enquanto que na casca foram encontrados os mesmo elementos, exceto Ag e Hg, evidenciando seu potencial como biomarcador. Neste sentido, estes resultados podem ser utilizados para estabelecer um panorama inicial e contribuir para futuros estudos relacionados a contaminantes inorgânicos na área estudada.

Major and trace element content was determined in golden mussel (Limnoperna fortunei) collected in the São Gonçalo Channel (Rio Grande City, Brazil). A microwave-assisted digestion procedure in closed vessels was applied to mussel decomposition and subsequent determination of elements by spectrometric techniques. Results showed that the mussel tissue contains Ag, Al, As, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, Li, Mg, Mn, Mo, P, Pb, S, Sn, Sr, Ti, V and Zn, while the same elements (except Ag and Hg) were quantified in its shell, demonstrating its potential as a biomarker. In this sense, these results can be used to establish an initial view and to contribute to further studies related to element contamination in the area under study.