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Per and polyfluoroalkylated substances (PFAS) are common additives in ski waxes for their water repellent characteristic. Abrasion of ski wax leaves PFAS on the snow surface, however, little is known about the distribution and concentration of PFAS in snow and soil due to skiing. In this study we analysed different ski waxes, snowmelts and soil from family skiing areas from Alpine locations using targeted high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) to understand more about PFAS distribution in the environment. In general, we found a very diverse PFAS pattern in the analysed media. PFAS level was higher in skiing areas compared to the non-skiing ones that were used as control. ∑target PFAS ranged between <1.7 ng L−1 and 143 ng L−1 in snowmelt, <0.62 ng g−1 and 5.35 ng g−1 in soil and <1.89 and 874 ± 240 ng g−1 in ski wax samples. Snowmelt was dominated by short-chained PFAS, while soil and wax contained both short and long-chained PFAS. Extractable organic fluorine (EOF) was several orders of magnitude higher for waxes (0.5–2 mg g−1) than for soils (up to 0.3 μg g−1), while total fluorine (TF) content of the waxes was even higher, up to 31 210 ± 420 μg g−1. We also showed that the ∑ target PFAS accounts for up to 1.5% in EOF content, showing that targeted LC-MS/MS gives a limited measure of the pollution originated from ski waxes and non-targeted analysis and EOF is necessary for a better overview on PFAS distribution. [ABSTRACT FROM AUTHOR]

Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) was applied for the determination of Br and I in hair strands of human individuals under treatment with synthetic thyroid hormones. Quantification relied on the use of Br- and I-spiked human hair strands prepared in-house as matrix-matched external calibration standards. The results obtained via LA-ICP-MS agreed with the corresponding Br and I concentrations as determined via pneumatic nebulization-ICP-MS after digestion via microwave-induced combustion. The spatial distributions of Br and I in the spiked hair standards were evaluated by spatially resolved LA-ICP-MS analysis and a homogeneous distribution was established upon scanning longitudinally along the hair strands and across the cross-section. Twenty-five human hair strands from volunteers were analyzed by LA-ICP-MS (7 individuals with hypothyroidism under treatment with synthetic thyroid hormones and 18 individuals considered healthy), and those from subjects under treatment with synthetic thyroid hormones presented a higher I concentration than those from subjects considered healthy. Limits of detection were 0.36 μg g−1 for Br and 0.14 μg g−1 for I, allowing trace level determination in human hair. [ABSTRACT FROM AUTHOR]

In this study, the microwave-induced combustion (MIC) method was evaluated for the sample preparation of the most consumed mushroom species in Brazil (Champignon, Shiitake, and Shimeji) and further halogen determination by ion chromatography (IC). For this, sample mass, combustion aid mass, and absorbing solution (H2O and 50 mmol·L−1, 100 mmol·L−1, or 150 mmol·L−1 NH4OH) were evaluated. Bromine and iodine concentrations, determined by IC, were lower than the limits of detection (LODs, Br: 6 mg·kg−1 and I: 24 mg·kg−1). Inductively coupled plasma mass spectrometry (ICP-MS) was also used for Br and I determination, and the LODs were lower (Br: 0.066 mg·kg−1 and I: 0.014 mg·kg−1) than those obtained by IC. Concentrations of Cl, obtained by IC, ranged from 523 mg·kg−1 to 13053 mg·kg−1 with LOD of 40 mg·kg−1. In turn, Br and I concentrations, obtained by ICP-MS, ranged from 2.49 mg·kg−1 to 5.50 mg·kg−1 and from <0.014 mg·kg−1 to 0.047 mg·kg−1, respectively. Fluorine concentrations, determined by IC, were always lower than LOD (23 mg·kg−1). The trueness of the proposed methods was evaluated by recovery tests using standard solutions and a reference material (RM NIST 8435). When using the standard solution, recoveries ranged from 95% to 103% for halogen determination by IC and from 105% to 109% for Br and I determination by ICP-MS. When using the RM, recoveries of 102% for Cl by IC and of 87% and 86% for Br and I by ICP-MS, respectively, were obtained. [ABSTRACT FROM AUTHOR]

Rationale: To increase the consumption of egg powder and its fractions a suitable quality control method is required to obtain more information on its nutritional composition. The proposed method enables the quantification of important elements for the functioning of the human organism, such as halogens and sulfur, in egg powder and its fractions. Methods: Up to 350 mg of egg powder or its fractions (egg white powder and egg yolk powder) were digested by microwave‐induced combustion using 20 bar pressure of oxygen. The analytes were absorbed in 100 mmol L−1 of NH4OH solution. The determination of halogens (chlorine, bromine, fluorine, and iodine) and sulfur was performed in a single analysis using ion chromatography with conductivity detection coupled to mass spectrometry. Results: Using the proposed method, spike recoveries between 99% and 104% for all analytes were obtained, and results agreed with certified values of reference materials (agreements were between 100% and 109%). The relative standard deviations were below 8%. The variation in elemental concentration over a wide range in different fractions (whole egg powder, egg white powder, and egg yolk powder) and different brands was also observed. Conclusions: The proposed method provides reliable information about minerals in whole egg powder and its fractions, contributing to better quality control of these products. Because these food products are widely consumed, these results suggest the safe ingestion levels of these elements. [ABSTRACT FROM AUTHOR]

Rationale: Bromine and iodine have important physiological functions; however, in inadequate concentration, they can also cause several physiological problems. Their mobility assessment in human organisms through biological sampling may help clarify some doubts related to metabolic routes, which are still not well elucidated. In this context, a suitable analytical method for this purpose should be developed. Methods: An analytical method for determining ultratrace levels of bromine and iodine in human nail samples was developed. Inductively coupled plasma mass spectrometry (ICP‐MS) using a conventional nebulization system was immediately chosen as the determination tool because of its powerful sensitivity and selectivity. Sample preparation methods including microwave‐induced combustion (MIC), microwave‐assisted extraction, and microwave‐assisted digestion were evaluated. The compatibility of the final solutions with ICP‐MS analysis was considered while the method was developed. Results: MIC was chosen as the most suitable method for the sample preparation for determining the levels of bromine and iodine in human nail samples using ICP‐MS. Unlike other sample preparation methods, this one fully eliminated interferences related to the carbon content and memory effects. Sample masses up to 100 mg were efficiently digested, and the analytes were quantitatively absorbed using only 50 mmol L−1 NH4OH solution. Recoveries ranged from 93% to 102%, and the relative standard deviation was < 8%. Conclusions: The proposed analytical method presents important characteristics for routine analysis. It allows ultratrace determination even when low sample masses are used because of the low blank values, reduced volume of reagents, and powerful detectability using ICP‐MS. [ABSTRACT FROM AUTHOR]

The daily use of cosmetics may expose consumers to localized skin problems and systemic effects caused by absorption of chemical elements. The requirements for suitable quality control and maximum limits for toxic and potentially toxic elements in cosmetics have attracted the attention of the scientific community and of the official institutions around the world. Maximum limits for chemical elements in some cosmetics have been set, but there are disagreements between them. In the same context, many analytical methods have been proposed in the literature, but several challenges during the sample preparation and determination steps related to the high complexity of cosmetics' matrices composition still remain. It is extremely difficulty to establish suitable methods, free of interference, even using modern technology. In this review, methods for determining toxic and potentially toxic elements in cosmetics used for make-up on the lips and on the eye area, covering the period since 2000, are presented. Techniques enabling direct analysis and those requiring a sample preparation step prior to the analysis are also discussed. This review focused on cosmetics for make-up on the lips and on the eye area because the risks of percutaneous absorption and oral ingestion of toxic and potentially toxic elements is higher than in other body regions. Image 1 • Trends and challenges for determination of elements in cosmetics used for make-up are discussed. • Cosmetics composition and problems associated with the presence of toxic elements are presented. • Sample preparation methods and techniques for analysis of cosmetics are detailed and discussed. • Advantages and disadvantages of analytical methods reported in literature are discussed. • Direct analysis methods used for cosmetics are covered. [ABSTRACT FROM AUTHOR]

A single analysis of hair for determining halogens (chlorine, bromine, fluorine, and iodine) and sulfur by ion chromatography with suppressed conductivity and mass spectrometry detection (IC-MS) was proposed. Inductively coupled plasma optical emission spectrometry (ICP OES) and inductively coupled plasma mass spectrometry (ICP-MS) were also used to compare the results. For this purpose, 300 mg of human hair were digested by microwave-induced combustion (MIC) using 20 bar of oxygen pressure. The analytes were absorbed in 100 mmol L−1 NH4OH. Trueness of the proposed method was evaluated by analysis of a CRM of human hair; by recovery tests, using standard solution at two levels (50% and 100%), and by comparison of results with those obtained by ICP OES (Cl and S) and ICP-MS (Br and I). Suitable recoveries (ranging from 92 to 105%) were obtained, and the results from CRM analysis did not differ significantly from those described in the certificate. Moreover, results obtained by IC-MS did not present significant differences (p > 0.05) from those obtained by ICP OES and by ICP-MS. Precision was evaluated in terms of repeatability and intermediate precision, and the relative standard deviations were always lower than 8%. The proposed method presented good accuracy and it is a reliable strategy for human hair analysis. Final digests obtained using the MIC method were fully compatible with all proposed determination techniques. Compared to others reported in the literature, the proposed method presents several advantages, especially given that it is possible to determine halogens and sulfur in a single analysis. [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]

In this study, two methods based on the use of diluted acids were developed: microwave-assisted wet digestion (MAWD) and microwave-assisted ultraviolet digestion (MAWD-UV). These methods are evaluated for the digestion of oral pharmaceutical drugs and further determination of elemental impurities from classes 1 (As, Cd, Hg and Pb) and 2A (Co, Ni and V) by inductively coupled plasma optical emission spectrometry (ICP-OES). Commercial drugs for the treatment of type 2 diabetes are used. No prior comminution is performed. For MAWD, the optimized conditions were 2 mol L−1 or 3 mol L−1 HNO3, 1 mL of 50% H2O2 and a 45 min or 55 min irradiation program. For MAWD-UV, the condition using 1 mol L−1 HNO3, 1.6 mL of 50% H2O2 and a 55 min irradiation program enabled the digestion of all samples. In this way, efficient methods are proposed for the digestion of commercial pharmaceutical tablets for further determination of class 1 and 2A elemental impurities (ICH Q3D guidelines). [ABSTRACT FROM AUTHOR]

(1) Background: Elevated atmospheric CO2 concentration affects the growth and development of the rice crop. In Southern Brazil, rice is traditionally produced with continuous irrigation, implying a significant amount of water used. Besides, continuous flooding favors the uptake of toxic elements such as arsenic (As) and cadmium (Cd). In this work, one Brazilian rice cultivar (IRGA 424) was tested for the effects of elevated CO2 concentration and different water regimes on rice yield, and As and Cd accumulation in grain. (2) Methods: Rice was grown in two CO2 concentrations (400 and 700 µmol mol−1) and two irrigation regimes (continuous and intermittent). It was evaluated the number of tillers, plant height, aboveground dry weight (ADW), water use efficiency (WUE), rice yield components, and As and Cd concentration in rice grain. (3) Results: Rice plants were taller and had a higher WUE when cultivated at e[CO2]. The ADW and the rice yield component were not affected by CO2 levels nor water regimes. Intermittent flood regimes had a lower average As concentration. The Cd concentration in the samples in both growing seasons and all treatments was below the limit of quantitation (8.76 μg kg−1). (4) Conclusions: Enhanced CO2 concentration did not affect rice yield, increased the WUE, and reduced As concentration in grains. Regarding water management, the intermittent regime enhanced WUE and promoted a reduction in As concentration in grains. [ABSTRACT FROM AUTHOR]

Abstract In this work, an analytical method for bromine and iodine determination in human saliva was proposed. A simple protocol based on centrifugation and direct analysis of supernatant by inductively coupled plasma mass spectrometry (ICP-MS) was investigated. Although this method was feasible for bromine determination, iodine was partially present in the supernatant and an agreement about 54% with reference value was obtained. In addition, microwave-induced combustion (MIC) and microwave-assisted dissolution were also evaluated. Using MIC, 0.2 mL of saliva added on 300 mg of microcrystalline cellulose were efficiently digested. A diluted solution (50 mmol L−1 NH 4 OH) was used for analytes absorption, and a reflux step of 5 min was applied to ensure quantitative recoveries of Br and I. Accuracy was evaluated by analyte recovery experiments, and recoveries between 94% and 98% were obtained. Microwave-assisted dissolution was evaluated for 2.0 mL of saliva using also a diluted alkaline solution (25 mmol L−1 NH 4 OH) and a microwave irradiation program of 35 min (including the cooling step). Results for this method agreed with those obtained using MIC. Although MIC has also been appropriated for further determination of Br and I in saliva, microwave-assisted dissolution can be considered a simpler sample preparation method and it was effective for high amount of sample (up to 2.0 mL). Moreover, final solutions were compatible with ICP-MS analysis, allowing the quantification of Br and I in human saliva at ultra-trace concentrations (limits of quantification were 0.052 μg mL−1 for Br and 0.022 μg mL−1 for I). Graphical abstract fx1 Highlights • Bromine and iodine can be determined at ultra-trace concentration in human saliva. • Proposed analytical methods are accurate for Br and I determination in human saliva. • Drawbacks of analytical methods reported in the literature were overcome. • Proposed analytical methods can be used in different research fields. [ABSTRACT FROM AUTHOR]

Objectives: to determine salivary electrolyte concentration of oral potentially malignant disorders (OPMD) and oral squamous cell carcinoma (OSCC) patients. A related systematic review was performed., Methods: Observational study. Unstimulated saliva from 18 patients with OSCC, 18 with OPMD, and 18 without oral lesions was collected. A biochemical analysis was performed to evaluate the salivary concentrations of potassium (K), phosphorus (P), sodium (Na), calcium (Ca), magnesium (Mg), zinc (Zn), copper (Cu), and iron (Fe). Kruskal-Wallis test was performed, and p < 0.05 was interpreted as statistically significant. The literature search for the systematic review retrieved 9 studies that associated salivary electrolyte levels with presence and progression of OSCC., Results: A highly significant increase was found in the salivary Mg levels in the OPMD group (5.41 µg/mL) in comparison with the OSCC (3.71µg/mL) and control group (3.51 µg/mL) (p = 0.041). No differences were observed in other salivary levels elements. The results of the systematic review revealed that one article indicated a decrease, and three papers reported an increase in salivary Na levels in patients with OPMD and OSCC. Two articles indicated a decrease in salivary K levels in OSCC, and the other two reported high Mg levels in OPMD and OSCC., Conclusion: High salivary Mg levels can be a potential biomarker indicating the presence of OPMD, however, the evidence is still contradictory and more studies are required.