Amberlite IRA-410 anionic exchange resin was evaluated as the binding layer for sampling V(V) by using Diffusive Gradients in Thin Films (DGT). V(V) was determined by inductively coupled plasma mass spectrometry (ICP-MS). Mass vs. time DGT deployments (ionic strength = 0.03 mol L NaNO, pH = 5.6 and T = 23.5 ± 0.5 °C) was characterized by excellent linear relationship (R = 0.9993) and a significant retention of V(V) by the binding layer. An exchange capacity of at least 40 μg V g resin was achieved for the proposed binding layer. The diffusion coefficient obtained (7.13 ± 0.6 10 cm s) agrees with the literature. The accumulation rate of V(V) was not significantly affected by ionic strength of solutions up to 0.03 mol L and for the entire studied pH range (from 3 to 9). Furthermore, when comparing the concentrations obtained using IRA-410-DGT and those obtained by direct measurement of the solution concentrations, the proposed approach provided a reduction of the ClO interference on V(V) determination by ICP-MS. Determination of V in normal mode (without collision cell) in solutions containing analyte:Cl concentration ratio up to 1:500,000 was not affected by interference of ClO polyatomic ion even when normal mode ICP-MS was used. Potential interfering ions on sampling V(V) by DGT (PO and SO) showed no significant effects on the accumulation rate of V(V). Laboratory tests performed using synthetic samples, natural freshwater and acid drainage water showed an excellent performance (recoveries from 93% to 110%). For in situ deployment, measurements of V(V) by the proposed approach was not significantly different (95.5%) from the value of dissolved V concentration.

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The toxic metal lead (Pb) can be harmful to human health in various manners, but is also considered as a distinguished tracer of environmental pollution since the relative abundance of its four stable isotopes with the atomic masses of 204, 206, 207, and 208 varies with the emission source. This study is focused on the Pb concentrations and isotope ratios in the particulate matter of the Brazilian city of Goiânia in order to determine the main Pb emission sources. Particulate matter samples were collected on clean Teflon filters during rainy and dry season in 2014 in the center of Goiânia city near main roads with a high traffic volume. Pb concentrations as well as stable Pb isotope ratios of the particulate matter samples were analyzed by inductively coupled plasma-mass spectrometry. To apply this analytical technique successfully, it was necessary to optimize parameters in case of acquisition time, detector dead time, and mass discrimination, which affect the measurement accuracy and precision. Results showed that Pb concentrations in Goiânia were different between rainy and dry season. Pb concentrations showed higher values and less variation in dry season than in rainy season. Pb isotope ratios demonstrated significant variations between dry and rainy season. An enrichment of Pb isotopes related toPb and Pb isotopes was observed in dry season. However, the comparison of the obtained isotopic Pb signature with data of potential Pb sources from previous studies indicated that traffic-related sources should be considered as main Pb source in the particulate matter of Goiânia. These assumptions were incorporated by the calculation of the contribution factor of Pb coming from traffic-related sources by applying binary mixing equations.

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