Concentrations and health risk assessment of total mercury in canned tuna marketed in Southest Brazil

The aim of this research was to determine total mercury (Hg) content in 69 canned tuna of 13 brands marketed in southwest Brazil. All values are reported in μg.g⁻¹ wet weight basis. Potential health risk was estimated on the basis of mercury concentration and average consumption (175 g/per week) of fish in Brazil comparing to PTWI of 1.6 μg.kg⁻¹ (FAO/WHO, 2010). A large variation in the concentration of mercury in different species was observed. Mean mercury concentration was 0.256 ± 0.215 μg.g⁻¹ with a highest value of 1.060 μg.g⁻¹ in a single can. In general average concentration was below the legislation of 1.0 μg.g⁻¹ for predatory species (BRASIL, 2010). Estimate weekly intake (EWI) varied 0.2–1.7 μg.kg⁻¹. For the analyzed brands and Brazilian fish consumption, no human health risk is likely to occur. However one brand was higher than PTWI of 1.6 μg.kg⁻¹ showing no safety for specific risk group. Further studies including specific data on canned tuna consumption in specific populations will be needed as well as the fish type, fish size and fishing location.     

Determination and health risk assessment of heavy metals in imported rice bran oil in Iran

In this current study, the contents of heavy metals including Pb, As, Cr, Cd, Zn, Cu, and Mn in imported rice bran oil in Iran were investigated with microwave digestion method based on an inductively coupled plasma optical emission spectrometry system (ICP-OES). The concentrations range of Pb, Cr, Cd, As, Zn, and Cu in rice bran oil samples were measured as 0.066–0.30, 0.008–0.014, 0.005–0.01, 0.047–0.01, 0.025–0.74 and 0.01–0.096 μg/g, respectively. A significant difference (p-value < 0.05) in the mean concentration of Pb in imported rice bran oils samples was observed. The sum of incremental lifetime cancer risk (ILCR) for heavy metals for children and adults were 2.6 × 10⁻⁴ and 2.4 × 10⁻⁵, respectively, which an acceptable level proposed values (10⁻⁴–10⁻⁶) by U.S. EPA. Moreover, the target hazard quotients (THQs) of As, Pb, Cr, Cd, Cu, and Zn for children were limited to between 1.17 × 10^-5 and 9.49 × 10⁻⁹, and in adults were limited to 2.33 × 10⁻⁷and 6.82 × 10^-7, which were lower than the acceptable limit (THQ < 1). There have been concerns regarding heavy metals since past up to now in all foodstuffs. We demonstrated in this study that there are traceable concentrations of heavy metals in six brand of rice bran oils.     

Squalene in oils and fats from domestic and commercial fryings of potatoes

Squalene was determined in commercial frying oils and fats (sunflower oil, cottonseed oil, corn oil, soybean oil, palm kernel oil, palm oil, vegetable shortening oil, and cooking fats) sampled during deep-frying of potatoes from 21 restaurants in Athens, Greece, and in domestic frying oils [virgin olive oil (VOO), vegetable shortening and sunflower oil] used during the domestic pan-frying and deep-frying of potatoes. The analyses were carried out after cold saponification of the oils followed by gas chromatography-mass spectrometry of the hexane extract. Quantification was carried out by reference curve, using standard squalene solutions. Fresh vegetable oils and fats were found to contain small amounts of squalene (10.2-49.3 mg/100 g oil or fat), with the exception of fresh VOO, which contained 454 mg/100 g. The squalene content of the frying oils was reduced during frying, its lower concentration found in cooked fats (5.9 mg/100 g fat) and its higher in fried VOO (428 mg/100 g oil) after the first frying session. Squalene appeared to be rather stable during frying. Its retention in used restaurant seed oils and fats remained over 50% even after 30 h of frying while a high recovery of 84-96% was observed during the domestic deep-frying of potatoes in VOO. It seems that by using VOO as frying medium a considerable amount of squalene is absorbed by the fried potatoes, thus becoming part of our diet.     

Determination of inorganic arsenic in Argentinean rice by selective HGAAS: Analytical performance for paddy,brown and polished rice

Inorganic As (iAs) species require strict monitoring in foodstuff due to their toxicity. Rice is of particular concern, with recent legislations establishing limits for these species. In this work we develop a method based on selective hydride generation atomic absorption spectrometry (HGAAS) for the determination of iAs in different types of rice (polish, parboiled, brown and paddy rice). The multivariate design of experiments used for optimization showed interactions between different factors involved in hydride generation. Matrix effects were systematically studied, where the flow rate of the carrier gas proved to be a critical parameter for the minimization of matrix interferences. Nevertheless, matrix-matching was found to be necessary for accurate quantification of paddy rice samples. Comparison of the iAs concentrations obtained by HGAAS and HPLC-ICP-MS showed non-significant differences between the methods. Analysis of 86 rice samples from the province of Entre Ríos showed relatively low concentrations of iAs (<282 μg kg⁻¹ for paddy rice and <120 μg kg⁻¹ for polished rice), regardless of total As concentrations (which ranged from 63 μg kg⁻¹ to 932 μg kg⁻¹), suggesting that the rice analyzed tends to accumulate As in its organic forms.     

Exposure to nickel through commercial premade baby foods: Is there any risk?

A study was performed to evaluate the risk regarding the presence of nickel in commercial premade baby foods: 26 ready meals, 31 fruits, 8 deserts and 20 paps. The analytical methodology used for the determination of nickel was dry ashing followed by graphite furnace atomic absorption spectrometry. Method detection limit (12.5 μg kg⁻¹) was obtained through a matrix matched calibration curve, using a nickel free commercial ready meal (meat).The results showed that 78 (91.8 %) samples contained nickel, with values up to 225.7 μg kg⁻¹. The group with the highest average concentration was the fruits (50.1 μg kg⁻¹) followed by the ready meals (40.2 μg kg⁻¹). Samples from organic farming presented higher detection frequency and average concentration (54.7 μg kg⁻¹) than the others. Using the average results, the tolerable daily intake proposed by EFSA (2.8 μg kg⁻¹ b.w.) was surpassed for the 2 year old age group, with daily ingestions up to 3.1 μg kg⁻¹ b.w.. This results highlight the risk promoted by the nickel present in commercial premade baby food.     

Formation of trans fatty acids during the frying of chicken fillet in corn oil

To assess effects of heated edible oils on intake of trans fatty acids (TFAs); the formation of TFAs in cooking conditions was investigated by a frying system model, in which chicken fillet was fried in a commercial corn oil at 170?°C, for 12 frying cycles. The main TFAs detected in chicken fillet were trans C18:2 fatty acids (FAs) and trans C18:3 FAs, which exhibited no significant differences among the frying cycles. Besides, the content of trans C18:1 FAs were very low in all samples on different frying cycles. The intake of TFAs was estimated to be 0.06?g/100?g when chicken fillet fried in this process was consumed. These results suggest that an ordinary frying process upon a commercial corn oil has little impact on the daily TFAs intake.     

Reference measurements of mercury species in seafood using isotope dilution inductively coupled plasma mass spectrometry

Species-specific isotope dilution inductively coupled plasma mass spectrometry (SS ID ICP-MS) and high-performance liquid chromatography (HPLC) were used to obtain accurate and SI traceable results for methyl mercury in seafood samples such as clam, oyster and fish homogenate. The mass fractions of (62.3 ± 2.3) μg kg⁻¹, (5.44 ± 0.36) μg kg⁻¹ and (531 ± 19) μg kg⁻¹ were obtained for MeHg (as Hg) in IAEA-461, IAEA-470 and IAEA-476, respectively. Direct isotope dilution mass spectrometry was performed for total mercury content then the content of inorganic mercury in selected samples was obtained by calculation. It was found that the content of inorganic Hg in IAEA-461, IAEA-470, and IAEA-476 was as: 328 μg kg⁻¹, 16 μg kg⁻¹, and 62 μg kg⁻¹, respectively. Mathematical modelling of analytical procedure and evaluation of all parameters influencing final results were adequate for validation of measurement procedure, establishing traceability and estimating expanded uncertainty. Developed procedures were successfully applied in the characterization process of fish homogenate candidate reference material and in the calculation of assigned values in the frame of IAEA-476 inter-laboratory comparison study. Compatibility between obtained results and those derived from the certification campaign, organized by International Atomic Energy Agency on the same sample matrix (<2.6 % difference) further validated performed ID ICP-MS protocols.     

Aluminium in infant foods: Total content,effect of in vitro digestion on bioaccessible fraction and preliminary exposure assessment

The objective of this study was to determine the total concentration and bioaccessible fraction of aluminium (Al) in 95 different baby food samples and estimate the exposure assessment. Total Al content was determined following oxidative microwave digestion by inductively coupled plasma optical emission spectrometry. An in vitro digestionmethod was optimized to evaluate the bioaccessible fraction. Total concentration and bioaccessibility varied according to the sample composition (saltypurees, fruit purees, infant drinks and petitsuisse). Petit suisse, soy-based drink and salty puree samples presented the highest total Al concentrations of 4170 μg kg⁻¹, 2860 μg kg⁻¹ and 2760 μg kg⁻¹, respectively. Bioaccessiblefraction varied from 0.5%–48% according to their composition.Exposure to Al was estimated and compared with the tolerable weekly intakes currently established. The results showed that the consumption of 3 portions/day of soy-based drink along the week could represent a concern.     

Distribution of essential and non-essential elements in rice located in a Protected Natural Reserve “Marjal de Pego-Oliva”

Anthropogenic agronomic practices could negatively affect the agricultural soil which is the main source for inorganic arsenic (i-As) contamination in rice fields due to flooding. The presence of essential elements could be impacted by food industry units operations. The aim of this study was to evaluate the effect of husking and polishing on mineral essential elements and inorganic As species in rice from Protected Natural Reserve “Marjal de Pego-Oliva”. The amount of all studied elements was significantly affected by husking (a decrease of Ca, Na and Pb, 360 to 101 mg kg⁻¹, 202 to 46.9 mg kg^-1 and 17.9 to 5.70 μg kg⁻¹, respectively) and by polishing (a reduction of Na, Mg, P, K, Ca and Cu, 46.9–26.8 mg kg⁻¹, 1600 to 481 mg kg⁻¹, 4050 to 1530 mg kg⁻¹, 2780 to 882 mg kg⁻¹, 101 to 53.7 mg kg⁻¹, and 3600 to 2840, μg kg⁻¹, respectively).The replacement of white rice (WR) to brown rice (BR) could enhance the daily dietary intake of essential elements to reach the dietary reference values and the maximum i-As (40.9 and 44.9 i-As μg kg^-1 for BR and WR, respectively) was below the maximum level recently established by European Food Safety Agency.     

Polycyclic Aromatic Hydrocarbons and Phthalic Acid Esters in Vegetables from Nine Farms of the Pearl River Delta, South China

This study investigated the occurrence of 16 polycyclic aromatic hydrocarbons (PAHs) and 6 phthalic acid esters (PAEs) in 11 vegetable species collected from nine farms of the Pearl River Delta, South China. Twelve PAH compounds and all PAE compounds were detected by gas chromatography coupled with mass spectrometry (GC-MS) in vegetables. The total concentrations of PAHs (Σ_PAHs) and PAEs (Σ_PAEs) ranged from 7.0 to 5353 μg kg⁻¹ dry weight (d.w.), with a mean value of 1173 μg kg⁻¹ d.w., and from 0.073 to 11.2 mg kg⁻¹ d.w., with a mean value of 3.2 mg kg⁻¹ (d.w.), respectively. The highest levels of Σ_PAHs and Σ_PAEs were found in Brassica juncea and Brassica parachinensis, respectively. For the same vegetable, the bioconcentration factors (BCFs; the ratio of contaminant concentration in plant tissue to the soil concentration) of PAHs (between 0.0037 and 5.5) are generally higher than those of PAEs (between <0.0001 and 0.61). It was also noted that there were great variations of organic contaminant levels, BCFs, and benzo[a]pyrene equivalent concentrations, which depend on the various contaminants, sampling locations, and vegetable species. The occurrences of PAHs and PAEs in this study are compared with those in other studies and their sources are discussed. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Evaluation of polycyclic aromatic hydrocarbons in Circassian cheese by high-performance liquid chromatography with fluorescence detection

Polycyclic aromatic hydrocarbons (PAH) in traditional/industrial smoked and unsmoked Circassian cheeses available in Turkish markets were analysed using solid-phase extraction, followed by high-performance liquid chromatography (HPLC) with fluorescence detection. Mean levels of a total of 9 PAHs in smoked traditional and industrial Circassian cheeses were 19.6 and 6.73 μg kg⁻¹, while levels in unsmoked traditional and industrial cheeses were 0.77 and 0.49 μg kg⁻¹, respectively. The dominant individual PAHs found were naphthalene and acenaphthene. Benzo[a]pyrene, a marker compound representing carcinogenic PAHs, was found in 90% and 30% of traditional smoked and unsmoked Circassian cheeses, 52% and 24% of industrial smoked and unsmoked cheeses, respectively. Correlation statistical analysis showed that benzo[a]pyrene was a good marker for total 9 PAHs in Circassian cheese samples (r_{B[a]P/sum of 9 PAHs} = 0.816, p < 0.01) as well as the best marker for 5 carcinogenic PAHs (r_{B[a]P/carcinogenic PAHs} = 0.904, p < 0.01). Risk assessment conducted using daily intakes of sum of 9 PAH levels found in both traditional and industrial smoked Circassian cheese samples showed high risk compared with unsmoked cheeses.     

Influence of frying conditions on acrylamide content and other quality characteristics of French fries

The objective of this work was to investigate the effect of processing frying conditions, simulating possible home and catering practices, in order to optimize the process to obtain a good final product limiting the acrylamide (AA) formation. Experiments were performed using commercially frozen pre-fried potato strips, a fixed initial frying temperature of 180 °C, two different fryers for domestic (A) and catering (B) use, and two potato-to-oil ratios (1/4 and 1/8 w/v). Several batches were fried at different fixed times, and for each batch the temperature of oil and stick surface were acquired by thermocouples. Analysis of AA and other quality characteristics (water and oil content, color, texture) of French fries were carried out. In all adopted frying conditions the increase of oil and potato surface temperature was faster in fryer A than in fryer B due to its peculiar manufacturing characteristics and employment mode. As a consequence, higher AA levels and a more cooked product were obtained using fryer A. With the immersion of a lower potato quantity (1/8 w/v), higher oil temperatures and AA levels and a more cooked product were obtained in shorter time in both fryers. Considering quality parameter results, the best quality characteristics were obtained in potatoes from fryer B between 10 and 13 min of frying with a product-to-oil ratio of 1/4 (around 250 ± 20 μg kg⁻¹ of AA), and after about 7 min of processing with a product-to-oil ratio of 1/8 (around 260 ± 50 μg kg⁻¹ of AA).     

137Caesium, 40Potassium and potassium in raw and deep-oil stir-fried mushroom meals from Yunnan in China

A number of wild, edible mushroom species (Baorangia bicolor, Boletus calopus, Boletus obsclereumbrinus, Butyriboletus roseoflavus, Rubroboletus sinicus, Rugiboletus extremiorientalis and Xerocomus sp.) were collected in 2017, from Yunnan (Yuxi prefecture) in SW China. Samples of raw and stir-fried pools of these specimens were analysed for radioisotopes ¹³⁷Cs (caesium) and ⁴⁰K (potassium), and for total K concentrations. On a whole (wet) weight (ww) basis, ¹³⁷Cs activity ranged from < 0.10 to 0.75 Bq kg⁻¹ for raw, and from 0.5 to 4.4 Bq kg^-1 in stir-fried mushrooms. Radiopotassium (⁴⁰K) activity ranged from 57 to 96 Bq kg⁻¹ ww for raw, and 170 to 370 Bq kg⁻¹ ww for stir-fried mushrooms, while the corresponding concentration ranges for total K were 2100–3400 mg kg⁻¹ ww (mean: 2800 ± 3900 mg kg⁻¹ ww), and 6000–13000 mg kg⁻¹ ww-(mean: 8700 ± 2100 mg kg⁻¹ ww), respectively. This data indicates that mushrooms from this region show negligible ¹³⁷Cs contamination with evidently higher activity levels of ⁴⁰K. The deep oil stir-frying process results in enrichment in the resulting meals for all three determinants. 100 g meal portions showed ¹³⁷Cs activity in the range < 0.08 to 0.44 Bq 100 g⁻¹ ww (mean 0.15 ± 0.12 Bq 100 g⁻¹ ww), and ⁴⁰K activity from 16 to 37 Bq 100 g⁻¹ ww (mean 24 ± 6 Bq 100 g⁻¹ ww). The consequent exposure from ⁴⁰K contained in a single 100 g serving and weekly (100 g x7) servings was equivalent to radiation doses in the range of 0.099 to 0.23 μSv and 0.68–1.6 μSv per capita (means 0.15 ± 0.04 and 1.1 ± 0.3 μSv). This is equivalent to doses in the range of 0.0017 to 0.0038 μSv kg^-1 bm day^-1 and 0.011 to 0.027 μSv kg^-1 bm week^-1 respectively (mean values of 0.0025 ± 0.006 μSv kg^-1 bm day^-1and 0.018 ± 0.004 μSv kg^-1 bm week^-1). Analogically to the annual ¹³⁷Cs radiation exposure resulting from high rates of annual consumption (20–24 kg per capita), the estimated annual dose of radiation from ⁴⁰K would range from 0.34 up to 0.92 μSv kg^-1 bm (mean 0.60 μSv kg^-1 bm). Thus in practice, high annual consumption rates of wild, stir-fried mushrooms as seen in Yunnan, would result in negligible internal doses from decay of artificial ¹³⁷Cs, relative to that from natural ⁴⁰K. The 100 g servings also contained between 590–1300 mg K making this local food one of the top dietary sources of nutritionally important potassium for local consumers.     

Airborne exposure to polycyclic aromatic hydrocarbons (PAHs) and urinary excretion of 1-hydroxypyrene of carbon anode plant workers

Workers in plants producing carbon anodes for aluminium electrolysis are exposed to PAHs containing coal tar pitch volatiles, pitch and coke. The aim of this study was to evaluate the suitability of urinary 1-hydroxypyrene to characterize respiratory exposure to PAH, which is most relevant for assessing individual health risks. Six workers in a carbon anode plant volunteered to take part in a personal air sampling and a biological monitoring programme lasting five consecutive 8-h shifts to determine occupational exposure to airborne PAHs and urinary excretion of 1-hydroxypyrene. Exposure to total PAH for all worksites varied from 3.99 to 120.6 μg PAH m⁻³ and for benzo(a)pyrene (BaP) from 0.17 to 4.88 μg BaP m⁻³. The concentration of 1-hydroxypyrene in post- and pre-shift urine samples was in the range (0.5–61.8 μmol 1-OHP per mol creatinine) and depended on the worksite. The Spearman rank correlation test showed a low but significant (P < 0.05) correlation of urinary 1-hydroxypyrene in the post- and pre-shift samples with respiratory pyrene exposure. The quantitative aspects of biological monitoring for the evaluation of respiratory PAH exposure were tested with a pharmacokinetic model. On the basis of individual pyrene exposure, excretion of urinary 1-hydroxypyrene during the working week was calculated for each worker. The results presented in this investigation indicate that biological monitoring of the pyrene metabolite 1-hydroxypyrene is a useful indicator of a general PAH exposure, but cannot replace personal air sampling for assessing the lung cancer risk of individuals.     

Bioaccessibility and Toxicity Assessment of Polycyclic Aromatic Hydrocarbons in Two Contaminated Sites

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous soil contaminants, and their bioaccessibility determines their environmental risks in contaminated land. In the present study, the residual concentrations of PAHs in the soils of two industrial sites were determined, and their bioaccessibility was estimated by the hydroxypropyl-β-cyclodextrin extraction (HPCD) extraction method. The results showed heavy PAH contamination at both site S1 (0.38–3342.5 mg kg^?1) and site S2 (0.2–138.18 mg kg^?1), of which high molecular weight (HMW) PAHs (4-, 5-, and 6-ring compounds) accounted for approximately 80%. The average bioaccessibility of PAHs at sites S1 and S2 was 52.02% and 29.28%, respectively. The bioaccessibility of certain PAH compounds decreased with increasing ring number of the molecule. Lower PAH bioaccessibility was detected in loamy and silty soil textures than in sandy soil. Moreover, among the soil properties, the dissolved organic matter, total organic carbon, total potassium, and total manganese concentrations had significant effects on the bioaccessibility of PAHs. The toxicity analysis showed that the composition and bioaccessibility of PAHs could affect their potential toxicity in soil. We suggest that bioaccessibility should be taken into consideration when assessing the toxicity of PAHs in soil, and more attention should be given to low-ring PAHs with high bioaccessibility.

     

Stability During Frying of Moringa oleifera Seed Oil Variety “Periyakulam 1”

The frying performance of the Moringa oleifera seed oil variety Periyakulam 1 (PKM 1) from India, extracted using cold press (CP) and n -hexane (H), during frying of potatoes and cod was studied especially as regards repeated frying operations. The oils were used for intermittent frying of potato slices and cod filets at a temperature of 175±5°C for 5 consecutive days. The chemical changes occurring in the oils were evaluated. Free fatty acid content, peroxide value, specific extinction at 232 nm, polar compounds colour and viscosity of the oils all increased, whereas the iodine values, smoke points, polyunsaturated fatty acid content, induction period and tocopherol concentration decreased. The effect of the oils on the organoleptic quality of these fried foods was also determined by expert panellists. The analytical and sensory data showed that the lowest deterioration occurred in cold pressure produced oil and the highest in n -hexane extracted oil. Therefore, cold pressure oil appears to be the most appropriate for frying. Potatoes and cod were also fried in virgin olive oil in order to have a direct comparison between the different oils. The results clearly indicated that virgin olive oil has the highest resistance to thermal deterioration during frying compared with the other two oils.     

In-solution derivatization and detection of glyoxal and methylglyoxal in alcoholic beverages and fermented foods by headspace solid-phase microextraction and gas chromatography–mass spectrometry

A simple and sensitive method for the simultaneous determination of glyoxal and methylglyoxal in alcoholic beverages and fermented foods was developed. This method involved simultaneous derivatization in solution with 2,2,2-trifluoroethyl hydrazine (TFEH) and headspace solid phase microextraction, followed by detection via gas chromatography-mass spectrometry (GC–MS). The method established herein can be summarized as follows. The sample was adjusted to pH 6.0 in a headspace vial, saturated with sodium chloride, and allowed to react with TFEH at 85 °C for 20 min. The formed derivatives were vaporized and adsorbed on divinylbenzene/carboxy/polydimethylsiloxane fibers. The TFEH derivatives were subsequently desorbed and analyzed by GC–MS, where the spectrum showed a single sharp peak. Under the established conditions, the quantification limits of glyoxal and methylglyoxal were 3.6 and 2.1 μg kg⁻¹, respectively, and the relative standard deviations were under 8% at concentrations of 20, 100 and 2000 μg kg⁻¹. All samples were detectable at typical glyoxal (62–4116 μg kg⁻¹) and methylglyoxal (11–2342 μg kg⁻¹) concentrations in beverages and foods.     

Determination and chemometric evaluation of the mineral profile of maize flours

Maize flour is a food rich in nutrients important for the proper functioning of the human body. Nevertheless, for the determination of metals in maize flour there are few studies, which raise concern about quality and its mineral composition for consumption. In this work, it was evaluated the concentration of essential (Ca, Cu, Fe, Mn, Mg, Cr and Zn) and non-essential (Cd and Cr) metals in yellow and white maize flour samples produced in Paraná State - Brazil. For this purpose, it was performed a sample treatment employing wet digestion in a digester block and determination of metals by atomic absorption spectrometry (AAS). The highest concentrations found in the flour were Ca (55.4 mg kg⁻¹) and Mg (86.9 mg kg⁻¹) and the lowest concentrations were Cr (0.11 mg kg⁻¹) and Cd (0.01 mg kg⁻¹). In yellow and white maize flour the highest concentration was for Mg, 81.5 mg kg⁻¹and 98.4 mg kg⁻¹, respectively. Principal component analysis (PCA) showed that some samples had a similar mineral profile, such as the relationship with the place of origin of the cereal.     

Essential and non-essential elements in Brazilian infant food and other rice-based products frequently consumed by children and celiac population

Rice and its derivatives are important source of essential and non-essential elements. Essential elements as cobalt (Co) and selenium (Se) are vital for human homeostasis. However, non-essential elements such as arsenic (As), cadmium (Cd) and lead (Pb) may be present in rice-based food and consequently, people can be exposed—especially children and the celiac population. This study aimed to determine essentials and non-essentials elements in rice-based products and baby food and also to evaluate nutritional risk by estimating the daily intake of non-essential elements. Regarding essential elements, Co and Se presented the highest concentrations in rice flour (56 μg kg⁻¹) and porridge (254 μg kg⁻¹), respectively. For non-essential elements, the highest concentrations of As, Cd and Pb were 104 μg kg⁻¹ (porridge), 16 μg kg⁻¹ (flour), and 188 μg kg⁻¹ (bread), respectively. Total As concentration in Brazilian rice-based baby food was <29 μg kg⁻¹. However, As-speciation revealed inorganic-As (i-As) as the main specie. The highest estimated daily intake of Cd, Pb and i-As were 1.37 (rice-based baby food); 10.39 (pasta); and 3.34 (pasta) μg d⁻¹, respectively. Therefore, continuous food monitoring for nutritional and toxicological purpose is necessary, especially concerning these particular populations and discussions for maximum levels of non-essential elements.     

Application of deep eutectic solvent as a disperser in reversed-phase dispersive liquid-liquid microextraction for the extraction of Cd(II) and Zn(II) ions from oil samples

A new, sensitive, and safe pretreatment method for the analysis of Cd(II) and Zn(II) ions in oil samples prior to flame atomic absorption spectrometry was developed. For the first time, a deep eutectic solvent is used as a disperser in reversed-phase dispersive liquid-liquid microextraction procedure. For this purpose, a deep eutectic solvent with low viscosity and miscible with both aqueous and organic phases is prepared by mixing glycolic acid and mandelic acid at a molar ratio of 2:1. The variables involved in this process were studied to provide high enrichment factors. Under optimized conditions, the linear ranges of calibration curves for Cd(II) and Zn(II) ions were obtained 0.30−20 and 0.50−30 μg L⁻¹, respectively. The obtained detection limits and enrichment factors were 0.12 and 0.18 μg L⁻¹; and 32.7 and 32.2 for Cd(II) and Zn(II), respectively. Repeatability of the proposed method, expressed as relative standard deviation, ranged from 2.7 to 4.1 % (n = 6, C = 1 μg L⁻¹ of each cation). Finally, the proposed method was successfully applied for the determination of Cd(II) and Zn(II) concentrations in various oil samples.