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Abstract An effective analytical method for bromine and iodine determination in human hair using interference-free inductively coupled plasma mass spectrometry (ICP-MS) was developed. Human hair was digested based on combustion reaction to obtain compatible solutions with ICP-MS analysis. Using microwave-induced combustion (MIC), masses of human hair ranging from 50 to 300 mg were efficiently digested. Only a diluted alkaline solution (100 mmol L−1 NH 4 OH) was used for the absorption of both analytes, which was fully compatible with ICP-MS analysis. Using these conditions low limits of detection were obtained (LOD of 0.01 μg g−1 for Br and 0.004 μg g−1 for I). Recovery tests at two levels (50% and 100%) using a standard solution or mixtures of the sample with certified reference materials (CRMs) were carried out to evaluate the suitability of proposed method and recoveries between 94% and 102% were always obtained. Accuracy was evaluated by analysis of a human hair CRM, and the Br and I concentrations obtained by the proposed method did not differ significantly from those described in the certificate. Repeatability (RSDs ≤ 4%) and reproducibility (RSDs ≤ 7%) of the results using proposed method were always very suitable. The digests obtained using the MIC method were fully compatible with ICP-MS and the interferences currently found using conventional digestion methods were completely eliminated. Ultra-trace concentrations of Br and I were determined in human hair, demonstrating that the proposed method is a suitable strategy, and it presents several advantages compared to others published in the literature. Graphical abstract Image 1 Highlights • The MIC method provided suitable digests for Br and I determination in human hair using interference-free ICP-MS. • Low limits of detection were obtained for Br and I. • Blank values were negligible and additional dilution step was not required. • The drawbacks of analytical methods for human hair analysis proposed in the literature were overcome. • The proposed analytical method can be used accurately and reliably by researchers in a variety of fields. [ABSTRACT FROM AUTHOR]

In this work, the use of complexing acids (HF and HCl) combined with HNO3 was carefully evaluated for the digestion of several types of lipsticks and further Cd and Pb determination by inductively coupled plasma mass spectrometry (ICP-MS). Creamy, opaque and shimmering lipsticks were digested using HNO3 (6 mL) or a mixture containing HNO3 (6 mL) plus HCl (0.5 or 2 mL) or HNO3 (6 mL) plus HF (2 mL). The results indicate that complexing acids are not required for the subsequent determination of Cd in all types of lipsticks evaluated. On the other hand, complexing acids were essential for ensuring quantitative results for Pb in shimmering lipstick. Thus, by using HNO3 combined with only 0.5 mL of HCl, it was possible to obtain quantitative results for Pb and Cd in lipsticks. Under these conditions, recoveries for Cd and Pb were between 95 and 103%. No statistical difference was observed between the results obtained using the proposed method (HNO3/HCl) and those obtained using HNO3/HF, where a complete dissolution of the lipsticks' inorganic fraction occurred. Moreover, by using HCl, HF was avoided and solutions more compatible with ICP-MS analysis were obtained. The limits of detection for Cd and Pb were 3 and 77 ng g−1, respectively. This method was applied for a variety of lipsticks, and the concentration of Cd and Pb ranged from ＜3 to 31 ng g−1 and 271 to 2250 ng g−1, respectively. [ABSTRACT FROM AUTHOR]

Abstract Microwave-assisted digestion using diluted acid under oxygen pressure is proposed for sample preparation of sports supplements and subsequent determination of Ca, Cu, Fe, K, Mg, Mn, Na, Zn, P and S by inductively coupled plasma-optical emission spectrometry (ICP-OES). In this sense, 1350 mg of sport supplement were digested in a microwave oven using only 6 mL of 5 mol L−1 HNO 3 under 5 bar of oxygen pressure during 15 min. Accuracy of proposed method was evaluated by recovery tests using a standard solution and using a certified reference material. Suitable recoveries (ranging from 86% to 108%) were obtained in both evaluations for all analytes. Results were compared with those obtained by conventional microwave-assisted digestion (without oxygen pressure) for further analytes determination by ICP-OES, and no statistical differences were observed (Student's t -test, confidence level of 95%, p > 0.05). The precision of proposed method was evaluated in terms of repeatability (RSDs ≤3%) and intermediate precision (RSDs ≤7%), and suitable results were obtained for all analytes. In addition, the limits of detection for all analytes using proposed method were lower than those obtained using conventional digestion in view of use a high sample mass and a diluted acid solution for sample digestion. The use of diluted acid reduces risks to analyst – since it eliminates the concentrated acid handling; reduces the consumption of reagents and, consequently, the waste generation, in accordance with the principles of green chemistry. Using the proposed method was possible to perform the determination of ten elements in a single analysis with suitable precision and accuracy. Six sport supplements were analyzed and the results are alarming because in most cases they were in disagreement with those informed on the label. Thus, a suitable quality control of sports supplements should be performed and the proposed method is a green, safe, accurate, precise and sensitive alternative for this purpose. Graphical abstract Unlabelled Image Highlights • The proposed method is a green, safe, accurate, precise and sensitive alternative to quality control of sports supplements. • The use of diluted acid nitric provided digests compatible with multitechnique determination, including IC and ICP-OES. • Proposed method was suitable for determination of ten elements in a single analysis with suitable precision and accuracy. • It was possible to determine metals and non-metals in sport supplements at low concentration. • Six sport supplements were analyzed and the results were in disagreement with those informed on the label. [ABSTRACT FROM AUTHOR]

Iron (Fe) is used in various cellular functions, and a constant balance between its uptake, transport, storage, and use is necessary to maintain its homeostasis in the body. Changes in Fe metabolism with a consequent overload of this metal are related to neurological changes and cover a broad spectrum of diseases, mainly when these changes occur during the embryonic period. This work aimed to evaluate the effect of exposure to Fe overload during the embryonic period of Drosophila melanogaster. Progenitor flies (male and female) were exposed to ferrous sulfate (FeSO 4) for ten days in concentrations of 0.5, 1, and 5 ​mM. After mating and oviposition, the progenitors were removed and the treatment bottles preserved, and the number of daily hatches and cumulative hatching of the first filial generation (F1) were counted. Subsequently, F1 flies (separated by sex) were subjected to behavioral tests such as negative geotaxis test, open field test, grooming, and aggression test. They have evaluated the levels of dopamine (DA), serotonin (5-HT), octopamine (OA), tryptophan and tyrosine hydroxylase (TH), acetylcholinesterase, reactive species, and the levels of Fe in the progenitor flies and F1. The Fe levels of F1 flies are directly proportional to what is incorporated during the period of embryonic development; we also observed a delay in hatching and a reduction in the number of the hatch of F1 flies exposed during the embryonic period to the 5mM Fe diet, a fact that may be related to the reduction of the cell viability of the ovarian tissue of progenitor flies. The flies exposed to Fe (1 and 5 ​mM) showed an increase in locomotor activity (hyperactivity) and a significantly higher number of repetitive movements. In addition to a high number of aggressive encounters when compared to control flies. We can also observe an increase in the levels of biogenic amines DA and 5-HT and an increase in TH activity in flies exposed to Fe (1 and 5 ​mM) compared to the control group. We conclude that the hyperactive-like behavior demonstrated in both sexes by F1 flies exposed to Fe may be associated with a dysregulation in the levels of DA and 5-HT since Fe is a cofactor of TH, which had its activity increased in this study. Therefore, more attention is needed during the embryonic development period for exposure to Fe overload. [Display omitted] • Progenitors flies exposed to Fe reduced ovarian cell viability. • F1 flies exposed to Fe in the embryonic period have increased DA, 5-HT and TH. • F1 Flies exposed to Fe in the embryonic period became hyperactive. • F1 Flies exposed to Fe in the embryonic period showed repetitive movements. [ABSTRACT FROM AUTHOR]