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Worldwide, cosmetics (especially eye shadows) are widely consumed and have a great impact on the economy. The aim of this study was to determine the multielement composition, focusing on essential and potentially toxic elements, in cosmetics (eye shadow) exposed to consumption in Brazil. Concentrations of 17 elements (Al, As, Ba, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, Sb, Se, Sr, Ti, V and Zn) were determined in samples (produced in China and Brazil) using a sequential optical emission spectrometer with inductively coupled plasma (ICP OES) after acid digestion, assisted by a closed digester block (6 mL of HNO

Worldwide, medicinal plants and herbal medicines are widely consumed. The aim of this study was to determine macro- (Ca, K, Mg, Na, and P) and microelements (Al, As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sb, Se, Si, Sn, Sr, V, and Zn) in medicinal plants and herbal medicines: “globe artichoke” - Cynara scolymus L., “devil’s claw” - Harpagophytum procumbens D.C., and “espinheira santa” - Maytenus ilifolia (Mart) ex Reiss. Concentrations of 24 (essential and toxic potentially) elements in samples from Brazil were determined using a sequential optical emission spectrometer with inductively coupled plasma optical emission spectrometry (ICP OES) after acid digestion, assisted by microwave radiation. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to carry out an exploratory analysis of samples. The elements were quantified (in μg/g): Al (20.24–1261.64), Ba (18.90–63.18), Ca (2877.6–19,957.40), Cr (0.28–1.38), Cu (4.16–21.99), Fe (8.54–627.49), K (1786.12–32,297.19), Mg (505.82–6174.52), Mn (0.40–205.64), Na (1717.23–18,596.45), Ni (< LoQ–0.99), P (35.12–2899.91), Se (1.52–3.71), Sn (1.53–12.43), Sr (52.33–84.31), V (< LoQ–0.24), and Zn (2.60–30.56). As, Cd, Co, Mo, Pb, and Sb, in all the investigated samples, were found to be below the limit of detection (LoD) and quantification (LoQ) values of ICP OES. These medicinal plants and herbal medicines can be sources of Ca, K, Mg, Na, P, Cu, Fe, Mn, Se, and Zn. All samples showed considerable levels of Al. PCA and HCA showed that the samples separated into two large groups.

In this work, a procedure is proposed for the direct analysis of powdered refreshments by fast sequential flame atomic absorption spectrometry (FS-F AAS), after a simple treatment of the sample. A full 23 factorial design was applied, and the variables chosen were as follows: acid concentration, acid type, and sonication time. Optimization provided the best conditions considering a mass of powdered refreshment of about 0.18 g diluted to a final volume of 15 mL with 0.5 mol L−1 HCl. The matrix effect was investigated, and external calibration was feasible for the determination of Cd, Co, Cu, Fe, Mg, Mn, Ni, Pb, and Zn. The limit of quantification (LoQ) obtained was between 0.6 (Cd) and 25 mg kg−1 (Pb). The analyte addition and recovery test were applied to evaluate the accuracy, and recovery percentage values ranging from 83.9 to 109.7% were obtained, which is considered adequate for quantitative analysis. Precision was expressed as relative standard deviation (% RSD); it was less than or equal to 5.0% (n = 7) for all analytes. The procedure was applied to 21 samples of powdered refreshment commercialized in Salvador (Brazil) and Buenos Aires (Argentina). The concentration range and average of the analytes in the samples (in mg kg−1) commercialized in Brazil (BZ) and Argentina (AG) were as follows: Co (BZ

The objective of this study was to determine the total content and estimate the bioaccessible fraction of Cu, Fe, Mn, and Zn in chia seeds (Salvia hispanica L.) by inductively coupled plasma optical emission spectrometry (ICP OES). For the evaluation of the total content, a method of acid digestion was developed, using a complete factorial design 23, in a digester block with reflux system using cold finger, and the variables chosen were as follows: volume of nitric acid, sulfuric acid, and hydrogen peroxide. Optimization provided the best conditions considering 5.0 mL of HNO3 65% m m−1, 0.5 mL of H2SO4 98% m m−1, and 3.0 mL of H2O2 30% m m−1. The detection limits, in μg g−1, were 0.18 (Cu), 0.22 (Fe), 0.28 (Mn), and 0.37 (Zn). The analyte addition and recovery test were applied to evaluate the accuracy and recovery percentage values ranging from 84 to 114% were obtained, which is considered adequate for quantitative analysis. Precision was expressed as relative standard deviation (% RSD). It was less than or equal to 7.6% (n = 10) for all analytes. The procedure was applied to 10 samples of chia seed commercialized in Salvador (Brazil). The following concentration ranges, in μg g−1, were found: Cu (12–24.2), Fe (53.2–108), Mn (29.8–84.2), and Zn (45.8–77.4). Bioaccessibility was assessed using an in vitro method that takes into account the entire gastrointestinal tract. The following bioaccessible fractions were obtained in percent: Cu (3.6–14), Fe (5.2–5.5), Mn (5.8–29.1), and Zn (

An acid digestion procedure of the forage palm (Opuntia ficus-indica Mill and Nopalea cochenilifera) employing a closed digestor block applied full 24 factorial design was optimized. The optimal conditions were HNO3 5.0 mol L−1, 2.0 mL of H2O2 30% m m−1, 120 min of digestion, and heating temperature of 180 °C. The certified reference materials of apple leaves (NIST 1515) and tomato leaves (Agro C1003a) were used to evaluate the accuracy of the analytical method. The concentrations of the macroelements were (in % m m−1) Ca (1.32–3.71), K (0.88–5.29), Mg (0.70–1.78), and P (0.03–0.32). For the microelements, the concentrations (in μg g−1) obtained were As (

Melipona quadrifasciata anthidioides is a species of stingless bee popularly known in Brazil as "mandacaia". Products derived from bees for food and therapeutic uses, have stimulated the evaluation of the chemical composition of geopropolis. Concentrations of 24 essential and potentially toxic elements were determined in geopropolis samples, using a sequential optical emission spectrometer with inductively coupled plasma (ICP OES) after microwave-assisted acid digestion. Principal component analysis (PCA) and Hierarchical cluster analysis (HCA) were used to carry out an exploratory analysis of the samples. The following elements were quantified (in mg Kg-1): Al (320,414.40-36,911.1), As (

Given the importance of knowing the real nutritional value of food, the main objective of this study was to evaluate the total elements concentrations and bioaccessibility of Ca, Cu, Fe, K, Mg, Mn, Mo, Na, P and Zn in linseed and sesame samples. A full 24 factorial design was applied to optimize the microwave assisted acid digestion of the samples. Total elements concentrations were obtained by inductively coupled plasma optical emission spectrometry (ICP OES). Extraction procedures were performed using the Unified Bioaccessibility Method (UBM) to evaluate the bioaccessibility. The highest total content, in μg g− 1, were observed for K (4526–9768), P (3418–7014) and Mg (2527–4633), whereas Mo (

The objective of this study was to analyze the effect of heat treatment on the bioaccessibility of major (K, Ca, Mg, P) and trace elements (As, Ba, Cu, Fe, Mn, Cd, Cr, Hg, Mo, Ni, Pb, Se, Sb, Sn, and Zn) in three different pulse species: Vigna unguiculata L. Walp (cowpea beans), Cajanus cajan L. (pigeon pea) and Lablab purpureus L. Sweet (mangalo). Analyte concentrations were determined in the samples by inductively coupled plasma mass spectrometry and inductively coupled plasma optical emission spectrometry. The results showed that thermal processing can affect the concentrations of the elements investigated in pulse samples. The influence of the heat treatment can range between legume species and chemical elements, as well as with the type of heat treatment, dry, wet, conductive heating and using microwaves.

In this paper, multivariate optimisation was applied to the development of an ultrasound-assisted multi-elemental extraction procedure to measure micronutrient minerals in coconut milk samples by inductively coupled plasma optical emission spectrometry (ICP OES). The factorial and Doehlert designs were applied to optimise the process variables. Using this approach, the optimal experimental condition for 1.0 g of coconut milk was determined: 10 min sonication time; 20.0 mL of HNO3 (1.0 mol L−1); and 5 min centrifugation time at 2000 rpm. The extraction percentage was calculated using the analyte concentration obtained by a total digestion procedure as a reference. Accuracy was assessed by analysing a certified reference material (NIST 1549). The proposed procedure was applied to the analysis of commercial samples of coconut milk, and the resulting concentration ranges, in μg g−1, were as follows: 5.8–131 (Ca)

In this work, the evaluation of the mineral profile and estimation of the bioaccessibility of essential and potentially toxic elements in honey samples was proposed. The experimental design and multivariate data analysis were applied as tool chemometrics. The acidic honey decomposition procedure using a cold finger digester block was proposed for analysis by inductively coupled plasma optical emission spectrometry (ICP OES). The analytical method presented good precision (

In this work, experimental design methodologies for the optimisation of analytical methods for the determination of inorganic constituents in tobacco products (cigar, shredded and rope) employing inductively coupled plasm optical emission spectrometry. Box-Behnken design was applied to optimise the digestion procedure of tobacco product samples using a closed digester block. The sample preparation was used dilute nitric acid, suitable for the concept of Green Chemistry. The operating conditions of spectrometer were optimised applying Doehlert design. The limits of quantification (LoQ) varied between 0.09 μg g−1 (Ba and Ti) and 116 μg g−1 (Na). The accuracy was confirmed by analysis of the certified reference materials (CRM) of oriental tobacco leaves (CTA-OTL-1), apple leaves (NIST 1515) and tomato leaves (CRM-Agro C1003a). The analytical method was applied for the determination of nineteen elements (Al, As, Ba, Ca, Cd, Co, Cu, Fe, K, Mg, Mn, Na, Ni, P, S, Sr, Ti, V and Zn) in tobacco products samples (cigar, shredded and rope). The results showed that the mean concentrations of macroelements were higher in cigar samples, the exception being Na concentration, which was higher for rope tobacco. For all samples, K concentration was the highest observed, since it is the nutrient most readily absorbed by the plant. Regarding the microelements and trace elements, cigar samples had higher contents of the six metals (Zn > Ba > Ti > Ni > Co > Cd) than did shredded or rope tobacco. The shredded tobacco samples presented higher concentration of Fe and for rope tobacco, the higher concentrations were for Al > Mn > Cu. In addition, principal component analysis (PCA) and hierarchical cluster analysis (HCA) were applied to discriminate the different tobacco products thought elemental composition, being cigar tobacco showed differences in relation to shredded and rope tobacco samples.

In this paper, multivariate optimization was applied for the development of microwave-assisted digestion using diluted nitric acid for the determination of essential (Ca, Co, Cr, Cu, K, Mg, Mn, Mo, Ni, P, Se, and Zn) and nonessential (Al, As, Ba, Pb, and Sr) elements in bean samples. Three variables (nitric acid concentration, temperature, and processing time) were regarded as factors in the optimization study. The optimum working conditions were as follows: 4.0 mol L−1 nitric acid, 190 °C, and a 15-min reaction time for step 4, which required a microwave heating program. The proposed procedure was then applied to bean samples from small producers of Bahia and to samples acquired from markets of Salvador, Bahia, Brazil. Pattern recognition techniques were applied to the data sets to characterize samples in relation to their geographical origin, species, and production mode. Some differences were found in the samples taken from the northeastern, central, and southern parts of Brazil.

Broccoli (Brassica oleracea L. var. Italica) is a vegetable food that belongs to the family Cruciferaceae, and it is a good source of vitamins and minerals. Among other characteristics, the kind of culture (conventional or organic), the climate of origin, and the way a vegetal will be consumed influence directly in the concentrations of minerals. The aim of this work was to determine mineral composition (Fe, Mn, Zn, K, Ca, Mg, and Na) of 16 broccoli samples collected in four cities of Bahia, Brazil, in summer and winter, from organic and conventional cultures. These elements were also determined in a lot of raw and cooked summer samples and then all results were evaluated using multivariate analysis. Broccoli samples were analyzed by inductively coupled plasma optical emission spectrometry after digestion with HNO3 and H2O2. The results expressed as milligrams of element per 100 g of sample demonstrated that the concentration ranges for conventional and organic broccoli varied, respectively, from 0.13 to 0.90 and 0.14–1.18, for iron; from 0.15 to 1.79 and 0.04–1.40, for manganese; from 0.20 to 1.58 and 0.17–1.28, for zinc; from 317.65 to 484.45 and 321.58–521.78 for potassium; from 7.14 to 153.50 and 9.38–131.55, for calcium; from 21.09 to 47.15 and 29.51–61.23, for magnesium; from 3.66 to 21.21 and 1.89–27.09 for sodium. The accuracy of the method was confirmed by analysis of a certified reference material of spinach leaves (NIST 1570a). The statistical evaluation of the obtained results showed that broccoli samples were not differentiated by city of origin, station, or culture. Nevertheless, by comparing raw and cooked samples, it was noticed a tendency of separation in the principal component analysis and hierarchical cluster analysis.

In this work, a method for the determination of phosphorus in biodiesel (B100) using flow injection analysis with spectrophotometric detection (FIA-SD) is described. Samples were digested using an acid mixture in a heating block. The phosphorus concentrations obtained by the (FIA-SD) method were similar to those obtained by the official method. Recovery tests show results between 98.6% and 101.0% for biodiesel produced from sunflower and between 102.1% and 113.5% for biodiesel produced from castor and soybeans. The limits of detection (LOD) and quantification (LOQ) obtained using the FIA system were 0.14 mg L−1 and 0.46 mg L−1, respectively.

A sequential injection methodology with chemiluminescence detection for the evaluation of residual ozone in waters is presented. The procedure is based on the reaction between luminol and ozone without catalysts. Linear calibration plots were obtained for ozone concentrations between 0.05 and 2.0 mg L−1, with a detection limit of 0.04 mg L−1. The developed methodology was applied to the determination of residual ozone in ozonized waters and the results complied with those furnished by the spectrophotometric reference procedure (relative deviations

Biological samples can be acid-digested using open or closed reaction vessels. Each one has advantages and limitations related to sample mass, contamination, operational temperature range, and losses of analytes. The latter may be critical when working with thermolabile chemical compounds. In the present work, focused-microwave and cavity-microwave ovens were employed for acid digestion of marine invertebrate samples (oyster, mussel and clam). The aim of this study was to evaluate losses of volatile species containing As, Cd, Pb, Se, and Zn, in both microwave systems, after an acid digestion procedure using nitric and sulfuric concentrated acids. The elemental determinations were performed by inductively coupled plasma optical emission spectrometry (ICP OES) with axially viewed configuration. Using a focused-oven, losses of volatile elements were always higher than 12%, when compared to cavity-microwave oven. High losses were observed for Pb and Cd, while Zn was not affected by volatilization in marine invertebrate samples. Standard reference material (Oyster tissue, NIST SRM 1566b) was used to check the accuracy.

The present article gives an overview of recent publications and modern techniques of sample preparation for food analysis employing atomic and inorganic mass spectrometric techniques, such as flame atomic absorption spectrometry, chemical vapor generation atomic absorption and atomic fluorescence spectrometry, graphite furnace atomic absorption spectrometry, inductively coupled plasma optical emission spectrometry, and inductively coupled plasma mass spectrometry. Among the most frequently applied sample preparation techniques for food analysis are dry ashing, usually with the addition of an ashing aid, and acid digestion, preferably with the assistance of microwave energy. Slurry preparation, particularly with the assistance of ultrasound, is increasingly used to reduce acid consumption and sample preparation time. Direct analysis of solid samples is gaining importance in the field of food analysis as it offers the highest sensitivity, avoids the use of acids and other aggressive reagents, make...

Food security has become a major concern of the world population and this is even more prominence in polluted areas. This study aimed to evaluate microbiological and toxic elements content of local food itens from Santo Amaro, Bahia. The determination of lead, cadmium, Escherichia coli (E. coli) and total coliform were carried out in coriander, cassava, okra, chicken muscle/liver, fish muscle and eggs. The population of total coliform and E. coli were estimated by the express count method using plates EC (AOAC 991.14) and accounting of colonies by colony counter. For toxic elements determination samples were digested using HNO3 and H2O2 following EPA 200.3 using a digester block with cold fingers. The determination of lead and cadmium was performed by inductively coupled plasma optical emission spectrometery (ICP OES). The mean total coliform has ranged from < 1 to 4.5 log CFU g-1. Coriander presented higher mean total coliform (4.5 log CFU g-1) and E. coli was higher than recommended levels. The range of toxic elements revealed higher concentrations of lead in chicken muscle (1.25-11.58 mg kg-1) and cadmium in eggs (0.45-1.06 mg kg-1). Finally, the risk to the inhabitants of Santo Amaro was evident and reinforces the importance of effective actions of local authorities.

The atemoya is a hybrid fruit obtained by crossing of cherimoya (Annona cherimola Mill.) with sweet sop (Annona squamosa L.). The information about chemical composition of atemoya is scarce. The mineral composition was evaluated employing Inductively Coupled Plasma Optical Emission Spectrometry (ICP OES) and the centesimal composition and the physico-chemical parameters were assessed employing procedures described in the AOAC methods. The total phenolic compounds (TPC) and total flavonoids (TF) were determined using spectroanalytical methods. Considering the Reference Daily Intake (RDI), the concentrations of K, Cu and Vitamin C found in atemoya were the highest, representing about 32, 23 and 37% of the RDI, respectively. The total carbohydrates were 32 g 100g-1 and the soluble solids was equivalent to (32.50 ± 0.03) °Brix. The result for TPC was 540.47 ± 2.32 mgGAE 100 g-1 and the TF was 11.56 ± 1.36 mgQE 100 g-1. The exploratory evaluation of 42 atemoya samples was performed through Principal Component Analysis (PCA), which discriminated green and ripe fruits according to their mineral composition. The elements that contributed most for the variability between green and ripe fruits were: Ba, Ca, Cu, K, Mg and P.

This study is a result of undergraduate student participation in the Environmental Chemistry discipline provided by the Chemistry Institute/UFBA. The students were involved in the development of passive samplers, a project of the LAQUAM (Environmental Analytical Chemistry Laboratory). The students' residences and other neighborhoods were used to create a passive sampling network, allowing the measurement of atmospheric levels of pollutants in urban areas and in those under industrial influence. The assembly of the passive samplers, including impregnation of filters and chemical analysis were part of the students' practice tasks. The results were analyzed taking into consideration the Brazilian legislation.