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This dataset includes spectra obtained through Raman spectroscopy of acetylsalicylic acid, paracetamol, and ibuprofen commercialized in San Lorenzo, Central Department of Paraguay. The pharmaceuticals were randomly purchased from pharmacies, official sales points, and street vendors, simulating purchases for self-consumption. These drugs were selected due to their high demand and consumption by the population, aiming to document and facilitate the identification of adulterations or alterations in their original structures caused by poor storage conditions. Additionally, this database will support multivariate studies for clustering using various techniques, both supervised and unsupervised, and will allow for signal processing and spectroscopic data handling.

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This work responds to the growing global demand for food, which requires improvements in agricultural production and sustainable management of natural resources. The focus is on soil erosion as a critical element in preserving agricultural productivity. From this perspective, the levels of radionuclides and chemical elements present in the soil, quantified through Gamma-Rays Spectrometry (GRS) and Energy Dispersive X-ray Fluorescence (EDXRF), were used to investigate soil redistribution over time. 27 soil samples ranging from 0 to 30 cm in depth were collected in an agricultural plot located in southern Brazil. Quantitative analysis indicated high mean concentrations of Fe (161 ± 7 gkg-1), Al (110 ± 17 gkg-1), Ca (2.6 ± 0.5 gkg-1), Mn (2.4 ± 0.3 gkg-1) and K (543 ± 165 mgkg-1) in comparison with the other detected elements. The quantification of 137Cs provided a mean inventory of 27 ± 17 Bqm-2. Using the proportional model, an estimated gross erosion rate of 28.2 tonha-1year-1 and a net soil deposition of 6.6 tonha-1year-1 were calculated. Therefore, a net soil loss of 21.6 tonha-1year-1 was experienced within the agricultural plot studied. The data set combination of both techniques with Principal Component Analysis (PCA) revealed correlations between the variables studied and the soil erosion dynamics. The PCA showed a tendency to separate the samples according to their sampling depth. Moreover, 137Cs behavior in soil proved to be similar to the behavior of elements found in fertilizers, like K. On the other hand, the individual influence of 137Cs was not enough to cause significant changes in the samples distribution in the scores plot, highlighting EDXRF as a promising technique to complement soil erosion studies.

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Electronic cigarettes (e-cig) have gained popularity around the world and its health risks demands more research. This study aims at characterizing e-cig liquids (e-liquids) and its constituents by Total Reflection X-ray Spectrometry (TXRF). The internal standard method was the quantification procedure employed. The spectrometer's performance was evaluated with one certified reference material and spiked samples. It was possible to quantify K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, and Pb in the e-liquids. Concentrations above the limit for potable water were found in 10 out of 38 samples. Principal component analysis was useful for identifying toxic samples. TXRF is a promising technique for e-liquids evaluation due to its simplicity and performance.

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Determining the maximum temperature reached in soil during burning is important when evaluating fire intensity. Forest conversion is an ongoing process in the Amazon ecosystem. It is of utmost importance to predict fire effects on soil properties and avoid damaging environmental systems. Spectroscopic methods combined with multivariate statistics may provide chemical and mineralogical information from soil. This study aims at predicting the maximum temperature reached in Oxisols from an Amazonian region in Brazil. Slash-and-burn and pasture samples collected after fire events and unburned forest soil samples submitted to heating (250-800 °C) were investigated. Energy-dispersive X-ray fluorescence (EDXRF) was used to acquire chemical data. The experimental procedure is rapid and requires minimal sample preparation and no hazardous chemical reagents. The EDXRF data, combined with partial least squares regression, were applied in controlled-heated samples from five different sites of forest, pasture, and slash-and-burn areas. Estimated temperatures for burned samples ranged from 317 to 609 °C. Considering the instrumental advantages and the achieved results, the use of EDXRF combined with multivariate analysis is a feasible alternative technology to evaluate fire effects in soil.

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As technology advances, counterfeiters improve their techniques reproducing banknotes with more accuracy. Spectroscopic techniques may be applied for characterization of these forgeries. The aim of this study was to develop a methodology for banknotes characterization employing portable X-ray fluorescence (pXRF) and portable Raman spectroscopy (RS) equipment for measurements in genuine and counterfeit Real (Brazilian currency) banknotes. Quantification of the metals in the ink and paper was carried out with pXRF data, using a sensitivity curve. pXRF spectral analysis was effective to discriminate between genuine and counterfeit bills. Moreover, the quantification of the metals enriched the analysis, since it was possible to compare elements concentration that are commonly found in genuine and counterfeit banknotes. The use of partial least square discriminant analysis (PLS-DA) applied to pXRF data was efficacious to identify fake banknotes and it may be used for further investigation about the provenance of forgeries. Principal component analysis (PCA) grouped forgeries from different seizures based on similarities in the elemental composition. The spectra obtained by RS allowed identification of characteristic bands of two pigments from the inks: phthalocyanine and diarylide. For the RS data, PLS-DA and PCA successfully discriminated R$ 50 genuine and fake banknotes.