Evaluation of various digestion procedures for trace element contents of some food materials

Dispersive micro-solid phase extraction (D-μSPE) of nickel on activated nanodiamonds@Bi2WO6 nanocomposite from water and food samples

This study presents an original nano-sorbent using activated nanodiamonds@Bi2WO6 to separate and enrich nickel ions from water and food samples. FTIR, XRD, FE-SEM, FE-SEM-EDX, EDS-TEAM, TGA, and BET were used to characterize the nanocomposite. It has a large surface area, active functional groups, and better reactivity. Ni(II) ions were determined as Ni(II)-PADAP chelates using UV-VIS spectroscopy. The parameters were studied and optimized, including pH (6), eluent type and volume (1 mL), ligand quantity (10 μg), sorbent dosage (20 mg), and contact time (1 min). The method has a low limit of detection (LOD) of 1.6 μg L-1, a limit of quantification (LOQ) of 5.3 μg L-1, a relative standard deviation of 4.5%, and a preconcentration factor of 10. The method was validated by applying to certified reference materials (BCR estuarine water 505 and 1573a NIST). The method was successfully applied to tap waters, industrial waste waters, and vegetables.

Micro solid phase extraction of lead and cadmium using functionalized nanodiamonds@CuAl2O4@HKUST-1 nanocomposite for FAAS analysis in food and water samples

This study focuses on the development and application of a novel nanocomposite (functionalized nanodiamonds@CuAl2O4@HKUST-1)-based µ-SPE method for the sensitive and selective extraction of Pb and Cd from food and water samples. The technique offers high sensitivity and selectivity, allowing accurate measurement of these metals at trace levels. The detection limit is 0.031 µg kg-1 for Cd and 0.052 µg kg-1 for Pb, with a relative standard deviation of 1.7 % for Cd and 4.8 % for Pb. The method was successfully applied to real samples and efficiently quantified Pb and Cd in food and natural water samples. The highest concentrations were found in red lentils (0.274 µg kg-1 Pb) and fresh mint (0.197 µg kg-1Cd), but still below recommended limits set by FAO/WHO (300 µg kg-1 for Pb and 200 µg kg-1 for Cd). It promises to ensure food safety, monitor environmental contamination, and informs regulatory decisions to protect public health.

Superfood consumers' exposure to selected heavy metals

Background: Superfood products are important components of the human diet, which may contain toxic heavy metals that have no beneficial function in the human body (e.g., cadmium, arsenic, mercury). Therefore, due to the high demand for these foods, maintaining their safety is a significant public health concern, resulting in an increasing number of studies in the field of health risk assessment due to population exposure to heavy metals. Aim: The aim of the study was to determine the concentration of selected heavy metals in individual superfood products. Methods: The research material consisted of 48 samples of selected superfood products such as flaxseed, chia seed, black cumin, goji berries, buckwheat, millet, almonds, quinoa and green tea. The collected samples were subjected to the mineralization process. In addition, an exposure assessment was performed by calculating the hazard quotient (HQ). Statistical analysis was performed using Statistica software for cadmium and arsenic. Results: The highest level of cadmium was observed in a sample of flaxseed (ground)-0.35 mg/kg. Again, the highest concentration of arsenic was found in green tea bags (21.94 mg/kg). The exposure assessment showed that the risk of adverse health effects is likely to occur with the consumption of flaxseed, almonds, quinoa and green tea at both the assumed average and maximum arsenic concentrations (HQ > 1). Conclusions: There are many foods on the market that contain heavy metals. The accumulation of various heavy metals in agricultural soils and edible crops should be regularly assessed to minimize public health problems.

Extreme low-temperature events can alleviate micronutrient deficiencies while increasing potential health risks from heavy metals in rice

Despite global warming, extreme low-temperature stress (LTS) events pose a significant threat to rice production (especially in East Asia) that can significantly impact micronutrient and heavy metal elements in rice. With two billion people worldwide facing micronutrient deficiencies (MNDs) and widespread heavy metal pollution in rice, understanding these impacts is crucial. We conducted detailed extreme LTS experiments with two rice (Oryza sativa L.) cultivars (Huaidao 5 and Nanjing 46) grown under four temperature levels (from 21/27 °C to 6/12 °C) and three LTS durations (three, six, and nine days). We observed significant interaction effects for LTS at different growth stages, durations and temperature levels on the contents and accumulation of mineral elements. The contents of most mineral elements (such Fe, Zn, As, Cu, and Cd) increased significantly under severe LTS at flowering, but decreased under LTS at the grain-filling stage. The accumulations of all mineral elements decreased at the three growth stages under LTS due to decreased grain weight. The contents and accumulation of mineral elements were more sensitive to LTS at the peak flowering stage than at the other two stages. Furthermore, the contents of most mineral elements in Nanjing 46 show larger variation under LTS compared to Huaidao 5. Accumulated cold degree days (ACDD, °C·d) were found to be suitable for quantifying the effects of LTS on the relative contents and accumulations of mineral elements. LTS at the flowering stage will help alleviate MNDs, but may also increase potential health risks from heavy metals. These results provide valuable insights for evaluating future climate change impacts on rice grain quality and potential health risks from heavy metals.

Investigation of Trace Elements in Vegan Foods by ICP-MS After Microwave Digestion

Veganism is gaining popularity around the world day by day. Vegan nutrition is a diet in which not all animal foods are used. A vegan diet does not contain meat, fish, milk and dairy products, and eggs and consists of vegetables, fruits, grains, legumes, and nuts. Vegan diets maintain energy balances in a wide variety of plant foods. So, health problems can be seen due to nutrient and mineral deficiencies in the long-term continuation of the vegan diet. Due to insufficient intake of vitamins and minerals such as vitamin D, vitamin B12, calcium, iron, and zinc, energy and protein balance in the body may not be achieved by vegan individuals. The contents of aluminum, chromium, manganese, iron, cobalt, nickel, copper, zinc, arsenic, mercury, cadmium, and lead have been analyzed by inductively coupled plasma mass spectrometer (ICP-MS) in 10 different vegan foods purchased from Turkey. Certified reference material (1547 peach leaves) was used for validating the digestion procedure. Dry, wet, and microwave processes were compared, and it was found that the microwave digestion method was the best. Element levels in the analyzed samples were found below the legal limits. The purpose of this work is to investigate the trace element content of various foods used in vegan nutrition.

Nutritional, Microbiological, and Toxicological Quality Assessment of Foods Sold in Urban and Suburban Markets in Burkina Faso

Food safety risks are becoming a public health problem with important socioeconomic consequences for human wellbeing, especially for pregnant women and infants. In this article, we describe findings from microbiological, toxicological, and nutritional quality assessments of foods from 5 localities in Burkina Faso, with the aim to provide baseline data on the quality of food and the risks to mothers and children. Samples for assessment included food sold in markets, stores, and restaurants (eg, cereals, oilseeds, vegetables, edible oils, powdered milk, dried fish, packaged water, ready-to-eat meals). The research team selected the samples using the random route method and analyzed them at the National Public Health Laboratory in Ouagadougou between January and December 2020. A total of 443 food samples were collected, of which 101 were analyzed for microbial contamination, 360 were analyzed for the presence of toxins, and 59 were analyzed for their nutritional value. The microbiological quality of 11.88% of the food samples was unsatisfactory, and 41.50% were contaminated with aflatoxins. At least 1 pesticide residue and cyfluthrin were detected in 58.10% of samples. The most detected contaminant (cyfluthrin) was found in 79.10% of the analyzed samples. A peroxide index higher than the normal value (10 mEq/kg) was found in 3.38% of the oil samples and 76.27% of the oil samples had a vitamin A content lower than the recommended limit of 11 mg/kg. This study is the first in Burkina Faso that provides baseline data on the quality of food and potential health risks to mothers and children in Burkina Faso. Considering the level of contaminants reported in this article, it is imperative to enhance routine monitoring of foods in the country.

Heavy element contents of vegetables and health-risk assessment in China

This study analyzed five heavy elements (HEs), including cadmium (Cd), chromium (Cr), mercury (Hg), lead (Pb), and arsenic (As), in fresh vegetables (i.e., legume, rhizome and potato, gourd, bulb, solanaceous fruit, leafy, and brassica; total: 7214) collected from 31 provinces in China from 2016 to the first half of 2017. By analyzing the concentration level of the five HEs in seven regions (the Northeast, North China, East China, South China, Central China, the Northwest, and the Southwest), except for As, average HEs concentrations were higher in the Southwest than that in the other six regions. According to the maximum permissible limit (MPL), the highest rate of HEs concentration above the MPL was found in the Southwest (11.038%). Analysis of variance (ANOVA) showed varying degrees of variability between regions and categories. By using principal component analysis (PCA), it was found that two principal components account for 73.79% of the total variance in the data. Together with hierarchical cluster analysis (HCA), concluded that Tibet was significantly different from the other 30 provinces. By calculating estimated daily intake (EDI) and the target hazard quotient (THQ), the EDI of Cr in the Southwest was the highest, with results of 1.2119 μg/kg/day for children and 0.8073 μg/kg/day for adults. North China had the highest total target hazard quotient (TTHQ) for HEs in vegetables ingested by children, with a result of 0.933.

Evaluation of metallic trace elements contents in some major raw foodstuffs in Burkina Faso and health risk assessment

Diet based on cereal, vegetables, oleaginous and dried fish are providing essential metallic elements. It can be also a source of exposure to toxic metallic elements. The aims of this study were to evaluate the contents on nine metallic trace elements (Fe, Zn, Mn, Co, Cd, Pb, Cu, Ni, Cr) in some major raw foodstuffs including rice, maize, peanut, tomato and dried fish in Burkina Faso and assess the health risk of these elements. Two hundred twenty-two samples were collected and analyzed by atomic absorption spectrometry. The health risk assessment was based on the United States Environment Protection Agency (USEPA) model. Iron and Zinc were the elements with the highest concentrations in the investigated foodstuffs. The iron highest median value (68.80 mg/kg) was observed in dried fish followed by maize (43.09 mg/kg) and peanuts (28.92 mg/kg). Rates of 77.95%, 66.66% and 32.5% obtained respectively fro tomato, maize and rice samples were above the maximum limit of lead set by Codex Alimentarius while 47.6%, 71.16% and 0% of maize, tomato and rice samples respectively have shown concentration above the maximum limit of cadmium. Chromium had shown higher contribution rate to the maximum daily intake of 167.11%, 34%, 2% and 8.53% for rice, maize and peanut respectively. A non-cancer risk situation has been observed on rice, maize and peanut consumption. None of the index risk values was above the threshold set by USEPA.

Effect of addition sites on bioaugmentation of tea polyphenols-NZVI/PE composite packing: Nitrogen removal efficiency and service life

Although efficient improvement of the nitrogen removal from wastewater by adding iron was achieved in wastewater process, the influence mechanism of addition sites is unclear. The study was based on the A/O-MBR treating simulated domestic wastewater, and tea polyphenol-nano zero-valent iron/polyethylene packing (TP-NZVI/PE) was added into the anoxic tank, aerobic tank and membrane effluent end of the process, respectively. The effect of the different addition sites on the nitrogen removal performance of A/O-MBR was investigated. Combine with the corrosion rate of NZVI on the packing surface to optimize TP-NZVI/PE addition site. The enhancement mechanism of TP-NZVI/PE under different addition site was explored through the calculation of the materials balance (carbon, nitrogen, phosphorus). The results showed that the pollutant removal of A/O-MBR was significantly increased with the TP-NZVI/PE added. In particular, the TP-NZVI/PE was added into the aerobic tank, and the pollutant removal rate was increased 31.71% (TN) and 53.00% (total phosphorus), respectively. Meanwhile, the service life of TP-NZVI/PE in the aerobic tank was 66 days. The anti-oxidation and dispersion of NZVI was improved with the encapsulation of tea polyphenols and support of packing, and it also played a certain slow-release effect, so that the service life of NZVI was further prolonged in aerobic condition. Combined with the material balance analysis, the result showed that the environmental structure made diversity in the aerobic tank by added the TP-NZVI/PE, and the simultaneous nitrification and denitrification process was achieved. The dependence of the denitrification process on the carbon source was greatly reduced. Besides, it promoted the adsorption and chemical precipitation process of the system for phosphor pollutant and achieved the denitrifying phosphorus removal performance.

Migration Behaviors of As, Se and Pb in Ultra-Low-Emission Coal-Fired Units and Effect of Co-Firing Sewage Sludge in CFB Boilers

The migration behaviors of As, Se and Pb in ultra-low-emission coal-fired units were investigated and the effect of co-firing of sewage sludge and coal was explored in circulating fluidized-bed (CFB) boiler units. Samples of feed fuel including coal and sewage sludge, fly ash, bottom slag and desulfurization slurry were collected from five CFB units with a capacity between 150 MW and 350 MW and two pulverized coal boiler (PC) units with a capacity of 350 MW and 600 MW. The majority of As, Se and Pb in coal is released during coal combustion and enriched in fly ash. As, Se and Pb in fly ash and bottom slag are associated with inorganic matter, of which As, Se and Pb associated with silicates and aluminosilicates account for more than 60%. In the wet flue gas desulfurization (WFGD) unit, more than half of the As, Se and Pb migrates to the solid fraction and the concentrations of As, Se and Pb in fine solid particles are much higher than those in coarse solid particles and the liquid fraction. The proportions of exchangeable As, Se and Pb or associated with organic matter in gypsum are higher than those of fly ash and bottom slag. According to the two studied CFB units with blending ratios of sewage sludge below 10%, co-firing with sewage sludge has little effect on the migration and transformation characteristics of As, Se and Pb. Under a long-term acidic leaching environment, Pb in combustion by-products is in the range of low risk, while As and Se are in the range of medium risk.

Concentrations and Health Risk Assessment of Metallic Trace Elements in Ready-to-Eat Braised and Flamed Chickens in Burkina Faso

Braised and flamed chickens known as "poulet bicyclette" are famous and popular street food in Burkina Faso. Although they are important sources of a wide range of essential trace elements for humans, they can also contain toxic metals. The aim of the study was to assess the concentrations and health risk of metallic trace elements (Ag, Cr, Cu, Mn, Fe, Co, Zn, Ni, Cd, Pb) in ready-to-eat braised and flamed chickens in Burkina Faso. The concentrations and health risk assessment were estimated by atomic absorption spectrometry and hazard quotient method, respectively. The concentrations of Cu (3.12 mg kg^-1), Fe (20.17 mg kg^-1), and Ni (0.22 mg kg^-1) were about 2 times higher in flamed chickens than in braised ones. Cd (0.45 mg kg^-1) and Cr (2.50 mg kg^-1) were 2 to 5 times more concentrated in braised chickens than flamed chickens. Pb was found in 72.72% of braised chicken and 62.06% of flamed chicken samples, above the maximum limit set by the JECFA. The daily intakes of Cu, Mn, Fe, and Zn contributed for less than 2% to the recommended daily intakes set by the Institute of Medicine of USA for both males and females, whereas Cr contributed for more than 20% from braised chicken. The estimated monthly intakes of Cd represented about 1.92-4.06% of the provisional tolerable monthly intake of Cd set by FAO/WHO. A non-cancer risk estimated as hazard index has been recorded at the maximum level of consumption for female consumer group for flamed chicken (HI = 2.14). The estimated cancer index risk in this study is below the reference value (10^-4) set by the United States Environmental Protection Agency (US EPA).

Advanced Methodologies for Trace Elements in Edible Oil Samples: A Review

Advanced methodologies were applied for the detection of some elements at trace levels in edible oils. Trace elements play a role in oil stability, quality of edible oils and fats. In the present study, problems were addressed related to simple, cheap, less time consuming and suitable pretreatment advanced methods for suitable sample introduction and calibrations as well as the strategies and techniques are discussed. The present review is aimed to discuss the significance of simplifying sample treatments are offered for trace elements in oils. The period covered by this review is last twenty years. However, the various applications of advanced methodologies including extraction and microextraction. The scope of spectrometric techniques used for the analysis of trace elements in edible oils was discussed by new instrumental development trends.

Relationship between heavy metals and alpha particles as a marker of environmental pollution in rice consumed in Najaf, Iraq

This study focuses on the emission of alpha particle rates (EAPR) and heavy metal concentrations (HMC) in the rice from Najaf markets. Nuclear Track Detectors and Flame Atomic Absorption Spectrophotometry, were used respectively. This study shows the pollution in the environment through AP and HM and also finds the relationship between AP and HM. The highest EAPR was found to be about 0.0249 mBq cm^-2 in the basmati rice, whereas, the lowest EAPR (0.0092 mBq cm^-2) was found in the Indian basmati rice. Highest Fe was found to be about 2.7237 mg/kg in basmati rice, while the lowest Fe (0.3997 mg/kg) was found in the USA basmati rice. Highest Cd was found to be about 0.0468 mg/kg in Iraqi Alnasryah rice, while the lowest Cd (0.0034 mg/kg) was found in Indian basmati rice. The most upper Pb was found to be about 0.2431 mg/kg in Babil Anbar Iraqi rice, while the lowest Pb (0.0695 mg/kg) was found in Indian basmati rice. Pb and Cd were lower than the FAO/WHO recommended limits (Pb, Cd: 0.50 mg/g) and the European Union acceptable dietary limits. In the combination of recent rice consumption data, an estimated weekly intake of toxic element was calculated for the Iraq population. A statistically significant correlation was found between EAPR and HMC in rice at the 0.05 level.

Determination of trace element contaminants in herbal teas using ICP-MS by different sample preparation method

In recent years, the consumption rate of herbal teas has increased rapidly. In this study, 28 different plants (fennel, linden, roots, chamomile, green tea, thyme, sage, rosemary, rosehip, ginger, balm, echinacea, blue tea etc.) used as herbal tea bags and leaves/flowers. Different types of herbal tea were prepared keeping boiling water in contact for ten min with herbal teas and were digested with HNO₃ and H₂O₂ in a microwave oven. In these samples, trace element concentrations (As, Ba, Cd, Co, Cu, Cr, Ni, Pb, Se, V, Zn) were determined by Inductively Coupled Plasma Mass Spectrometry. The analytical performances were assessed as linearity, the limit of detection, limit of quantification, specificity/selectivity and recovery (%). The recovery values changed between 88 and 112%.

Presence of cadmium residues in muscle, liver and kidney of Bubalus bubalis and histological evidence

Cadmium (Cd) concentrations were evaluated in the samples of kidney, liver and muscle of sixty-six buffaloes regularly slaughtered. Forty were raised in Campania, in the territory between the province of Naples and Caserta and twenty-six were bred in Apulia, in the province of Bari. Two aliquots were prepared for the renal and hepatic samples: one intended for the chemical analysis and the other one intended for histological investigations. Muscle samples were the subject of purely chemical investigation. In the group of forty animals raised in the Campania region, the limits imposed by EC Reg. 1881/2006 and EC Reg. 488/2014 were exceeded in three renal samples, which showed values of 1.53, 1.22 and 1.1 mg/kg respectively; in three hepatic samples, which presented values of 0.72, 0.64 and 0.61 mg/kg, and in five muscle samples, with values of 0.16, 0.16, 0.09, 0.08 and 0.07, respectively. On the other hand, in the group of animals raised and slaughtered in the province of Bari, none of the twenty-six samples examined exceeded the limits imposed by the European regulations. The histological analysis showed typical, but not pathognomonic lesions in the renal samples from the animals raised in the provinces of Naples and Caserta. The levels of Cd contamination found in the samples examined suggest that it would be correct to exclude from the human consumption, as it happens for the equines, the kidney and the liver, especially from the animals raised in some geographical areas with a high rate of pollution.

Developmental selenium exposure and health risk in daily foodstuffs: A systematic review and meta-analysis

Selenium (Se) is a trace mineral and an essential nutrient of vital importance to human health in trace amounts. It acts as an antioxidant in both humans and animals, immunomodulator and also involved in the control of specific endocrine pathways. The aim of this work is to provide a brief knowledge on selenium content in daily used various foodstuffs, nutritional requirement and its various health consequences. In general, fruits and vegetables contain low content of selenium, with some exceptions. Selenium level in meat, eggs, poultry and seafood is usually high. For most countries, cereals, legumes, and derivatives are the major donors to the dietary selenium intake. Low level of selenium has been related with higher mortality risk, dysfunction of an immune system, and mental failure. Selenium supplementation or higher selenium content has antiviral outcomes and is necessary for effective reproduction of male and female, also decreases the threat of chronic disease (autoimmune thyroid). Generally, some advantages of higher content of selenium have been shown in various potential studies regarding lung, colorectal, prostate and bladder cancers risk, nevertheless results depicted from different trials have been diverse, which perhaps indicates the evidence that supplementation will merely grant advantage if the intakes of a nutrient is deficient. In conclusion, the over-all people should be advised against the usage of Se supplements for prevention of cardiovascular, hepatopathies, or cancer diseases, as advantages of Se supplements are still ambiguous, and their haphazard usage could result in an increased Se toxicity risk. The associations among Se intake/status and health, or disease risk, are complicated and need exposition to notify medical practice, to improve dietary recommendations, and to develop adequate communal health guidelines.

Determination of selected elements in canned food sold in Jordan markets

In this study, the concentrations of seven heavy metals including As, Cd, Cr, Cu, Ni, Pb, and Zn in imported canned food samples of different brands including tuna, beef, sardines, and mushroom were determined. Samples were collected from popular Jordanian market, Irbid city, Northern Jordan (44 samples of each type). The metal concentrations in canned food samples were found to be in the range of 1.85-4.50 μg/g for As, 0.42-0.58 μg/g for Cd, 0.47-1.67 μg/g for Cr, 0.73-0.90 μg/g for Cu, 1.08-2.77 μg/g for Ni, 2.5-3.0 μg/g for Pb, and 0.43-2.25 μg/g for Zn. Results revealed that As and Pb have the highest concentrations in all samples analyzed, whereas, the lowest concentrations obtained were in Cd. For example, in canned sardine, the mean concentrations of heavy metals are 0.43 μg/g for Zn, 2.50 μg/g for Pb, 1.74 μg/g for Ni, 0.80 μg/g for Cu, 0.47 μg/g for Cr, 0.42 μg/g for Cd, and 1.85 μg/g for As. Whereas, the mean concentrations in canned tuna were 3.48 μg/g for As, 0.47 μg/g for Cd, 0.53 μg/g for Cr, 0.73 μg/g for Cu, 2.77 μg/g for Ni, 2.80 μg/g for Pb, and 1.63 μg/g for Zn. The results of this study indicated that the concentration of the tested elements including As, Cd, Cr, Ni, and Pb in canned food samples sold in Jordanian markets exceeded the permissible limits set by health organizations such as FAO/WHO. The results were compared with the literature values.

Influence of Digestion Procedure and Residual Carbon on Manganese, Copper, and Zinc Determination in Herbal Matrices by Atomic Absorption Spectrometry

Mineralization to the complete oxidation of sample carbon component does not always assure the best analyte recovery. Particular attention should be paid to the presence of silicon in the investigated plant sample and especially in the certified reference material for which Si content is scarcely given by the providers. During mineralization without addition of the hydrofluoric acid, the residual carbon may block silica surfaces and increase availability of an analyte for its spectral determination in the solution. This issue is of particular relevance because standard protocols for digestion of plant matrices often do not support hydrofluoric acid addition. Several procedures recommended for decomposition of herbal plants were applied for the respective certified reference material and examined in detail. Manganese, copper, and zinc contents were analyzed in all samples by the flame atomic absorption spectrometry. Additionally, the residual carbon was determined in all mineralizates. Silicon content was analyzed by the X-ray fluorescence method. The best recoveries were observed for samples characterized by relatively high residual carbon.

Analysis of trace metal concentrations in raw cow's milk from three dairy farms in North Gondar, Ethiopia: chemometric approach

Concentrations of essential (Cu, Mn, and Zn) and toxic (Cr, Cd, and Pb) trace metals in 30 raw cow's milk samples were quantified using flame atomic absorption spectrometry. The samples were collected from the Nara-Awudarda, Tana-Abo, and Kosoye Amba-Rass sites in North Gondar, Ethiopia, preserved in a deep freezer (-20 °C), and then digested by Kjeldahl apparatus with HNO₃/H₂O₂ (5:2; v/v) at 300 °C for 2.5 h. The data were subject to principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA). Overall hazard quotient (HQ) and carcinogenic risk (CR) values were also estimated to assess metal-related health risks. The mean concentrations of Cr, Mn, Cu, Zn, Cd, and Pb in the milk samples ranged 0.468-0.828, 1.614-2.806, 0.840-1.532, 1.208-5.267, ND-0.330, and ND-0.186 mg/kg, respectively. The lowest values were obtained for Kosoye Amba-Rass milk samples, while the highest were found for those collected from Nara-Awudarda milk samples, probably due to high mineral enrichment and metal leaching (especially Cd and Pb) from coal deposits. PCA revealed clustering of samples with respect to their geographic origin. Validation of PLS-DA model showed 100% classification efficiency using external validation samples and detected Cd and Cu as trace metal markers. The HQ and CR values were within the safe level; however, the former is close to the alert threshold level for Nara-Awudarda milk samples. Thus, further studies on common foodstuffs, constituting a higher proportion in the local diet, are required in this area to provide a complete risk assessment.

Ultrasonic energy enhanced the efficiency of advance extraction methodology for enrichment of trace level of copper in serum samples of patients having neurological disorders

An innovative dual dispersive ionic liquid based on ultrasound assisted microextraction (UDIL-μE), for the enrichment of trace levels of copper ion (Cu²⁺), in serum (blood) of patients suffering from different neurological disorders. The enriched metal ions were subjected to flame atomic absorption spectrometry (FAAS). In the UDIL-μE method, the extraction solvent, ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate [C₄mim][PF₆], was dispersed into the aqueous samples using an ultrasonic bath. The(PAN) 1-(2-pyridylazo)-2-naphthol was used as ligand for the complexation of Cu ion in IL (as extracting solvent). The various variables such as sonication time, pH, concentration of complexing agent, time and rate of centrifugation, IL volume that affect the extraction process were optimized. The enhancement factor (EF) and detection limit (LOD) was found under favorable condition was 31 and 0.36μgL^-1, respectively. Reliability of the proposed method was checked by relative standard deviation (%RSD), which was found to be <5%. The accuracy of developed procedure was assured by using certified reference material (CRM) of blood serum. The developed procedure was applied successfully to the analysis of concentration of Cu ion in blood serum of different neurological disorders subjects and referents of same age group. It was observed that the levels of Cu ion was two folds higher in serum samples of neurological disorders patients as related to normal referents of same age group.

A simple design for microwave assisted digestion vessel with low reagent consumption suitable for food and environmental samples

The objective of this work is to prepare a cost-effective, low reagent consumption and high performance polytetrafluoroethylene (PTFE) vessel that is capable to work in domestic microwave for digesting food and environmental samples. The designed vessel has a relatively thicker wall compared to that of commercial vessels. In this design, eight vessels are placed in an acrylonitrile butadiene styrene (ABS) holder to keep them safe and stable. This vessel needs only 2.0 mL of HNO₃ and 1.0 mL H₂O₂ to digest 100 mg of biological sample. The performance of this design is then evaluated with an ICP-MS instrument in the analysis of the several NIST standard reference material of milk 1849a, rice flour 1568b, spinach leave 1570a and Peach Leaves 1547 in a domestic microwave oven with inverter technology. Outstanding agreement to (SRM) values are observed by using the suggested power to time microwave program, which simulates the reflux action occurring in this closed vessel. Taking into account the high cost of commercial microwave vessels and the volume of chemicals needed for various experiments (8-10 mL), this simple vessel is cost effective and suitable for digesting food and environmental samples.

Comparison of Digestion Methods for the Determination of Trace Elements and Heavy Metals in Human Hair and Nails

BACKGROUND

Microwave is the most reliable sample digestion method. However, it requires expensive microwave digester automation and has relatively low productivity. In this study, three non-automated digestion methods, i.e. wet acid digestion using nitric acid (HNO₃) and hydrogen peroxide (H₂O₂), wet acid digestion using HNO₃, and dry washing, are compared in order to determine the best approach.

METHODS

Certified reference material IAEA-086 (International Atomic Energy Agency, Austria) and hair and nail samples from 20 female students of Universiti Kebangsaan Malaysia, aged 19 to 30 years, were collected and analysed using the three digestion methods.

RESULTS

For hair samples, analysis of variance of repeated measures showed significant differences in the level of all elements (P < 0.001) between the three methods. For nail samples, only the copper (Cu) level showed no significant difference (P = 0.100) between methods. Wet acid digestion using HNO₃ and H₂O₂ showed the best within- and between-run relative standard deviation (RSD) values, with within-run RSD for all elements, except for selenium (Se), < 5%. The between-run precision ranges from 6.14% to 17.96% for hair and from 3.53% to 11.52% for nail samples. Wet acid digestion using HNO₃ and H₂O₂ showed both good accuracy and precision for manganese (Mn) and magnesium (Mg), with percentage recoveries of 110% and 96.9%, respectively. All elements show higher method detection limit (MDL) values than the previous study: 0.05 μg/g Mg for wet acid digestion using HNO₃, 0.02 μg/g Se for wet acid digestion using HNO₃ and H₂O₂, and 0.2 μg/g Mg for dry ash method.

CONCLUSION

Wet acid digestion using HNO₃ and H₂O₂ proved to be the best method in terms of precision, accuracy, recovery, and MDL. However, only Mn and Mg showed adequate precision, accuracy, and percentage of recovery.

Content of micronutrients, mineral and trace elements in some Mediterranean spontaneous edible herbs

Background

The analysis of mineral elements composition was determined in three wild edible herbs (Cichorium intybus L., Sonchus asper L. and Borago officinalis) collected in seven different sampling sites which were characterized by different pollution grade. The detection of mineral elements (Ca, K, Mg and Na), micronutrients (Cu, Fe, Li, Mn and Zn) and heavy metals (As, Cd, Hg, Ni and Pb) was performed.

Results

The results obtained show that in most cases a direct relationship appeared between the amount of elements and the sampling sites. The highest concentrations of heavy metals were found in samples grown in polluted soils. These evaluations showed that contaminants in plants may reflect the environmental state in which they develop.

Conclusion

The examined species are a good source of mineral elements and micronutrients, making them particularly adapt to integrate a well-balanced diet. The accumulation of heavy metals showed that contaminants in plants may reflect the environmental state in which they develop. Results showed high concentrations of heavy metals in samples taken in locations characterized by high human activity and in some samples from the local market, of which no one knows the collection area.

Correlation of manganese with thyroid function in females having hypo- and hyperthyroid disorders

The aim of present study was to compare the level of manganese (Mn) with thyroid functions, thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxin (FT4) of females having hyper- (HPRT) and hypothyroid (HPOT) disorder. For comparative study, females of the same age group (16-30 years) having no thyroid disorders were selected as referents. The serum samples were acid digested prior to analysis by electrothermal atomic absorption spectrometry. The validity and accuracy of the methodology was checked by a certified sample. The resulted data indicated that the mean values of Mn in serum samples of females have hyperthyroidism was significantly higher than referent subjects (p < 0.01), while lower values of Mn was observed in serum samples of hypothyroid patients. The mean values of FT3 and FT4 were found to be lower while TSH higher is in HPRT patients than age-matched healthy control females (p = <0.01). The reverse resulted data of these thyroid hormones was observed in HPOT patients (0.003).

Levels of selected metals in leaves of Cannabis sativa L. cultivated in Ethiopia

Background

Cannabis sativa L. is one of the illicit drug bearing plants. Cannabis products are the most widely trafficked drugs worldwide. The highest levels of cannabis production in the world take place in the African continent. A small volume of cannabis is produced in rural areas of Ethiopia, of which a small portion is exported to neighboring countries and the majority is consumed at home. The literature survey revealed that there is no report on the metal contents in cannabis cultivated in Ethiopia. The main objective of this study is to determine the level of selected metals in leaves of Cannabis sativa L. cultivated in Ethiopia.

Methods

Cannabis sativa L. samples were collected from Metema (Amhara Region), Mekelle (Tigray Region), Sheshemene (Oromia Region) and Butajira (South Nations Nationality and Peoples (SNNP) Region) of Ethiopia. After proper sample pretreatment, the volumes of reagents used, digestion temperature and digestion time were optimized and using the optimized conditions the levels of metals were determined by flame atomic absorption spectrometry.

Results

The accuracy of the optimized procedure was evaluated by analyzing the digest of the spiked samples with standard solution and the percentage recoveries varied from 88 to 103%. The levels of metals determined (µg/g dry weight) were in the ranges Ca (657–1,511), Zn (321–380), Ni (124–172), Cu (122–176), Cd (3–10), Pb (8–10), and Cr (4–8). Zn was with the highest concentration among trace metals.

Conclusion

A statistical analysis of variance (ANOVA) at 95% confidence level indicated that there is a significant difference in the levels of all the metals between the four sample means except Pb. The results indicate that the content of Pb and Cd exceeds the permissible amount for medicinal plants which form the raw materials for the finished products set by World Health Organization (WHO).

Levels of essential and non-essential metals in ginger (Zingiber officinale) cultivated in Ethiopia

BACKGROUND

Ginger (Zingiber officinale Roscoe) is a common condiment for various foods and beverages and widely used worldwide as a spice. Its extracts are used extensively in the food, beverage, and confectionary industries in the production of products such as marmalade, pickles, chutney, ginger beer, ginger wine, liquors, biscuits, and other bakery products. In Ethiopia, it is among the important spices used in every kitchen to flavor stew, tea, bread and local alcoholic drinks. It is also chiefly used medicinally for indigestion, stomachache, malaria, fevers, common cold, and motion sickness. The literature survey revealed that there is no study conducted on the determination of metals in ginger cultivated in Ethiopia. Hence it is worthwhile to determine the levels of essential and non-essential metals in ginger cultivated in Ethiopia.

METHODS

The levels of essential (Ca, Mg, Fe, Zn, Cu, Co, Cr, Mn, and Ni) and non-essential (Cd and Pb) metals in ginger (Zingiber officinale Roscoe) cultivated in four different regions of Ethiopia and the soil where it was grown were determined by flame atomic absorption spectrometry. 0.5 g of oven dried ginger and soil samples were digested using 3 mL of HNO3 and 1 mL of HClO4 at 210°C for 3 h and a mixture of 6 mL aqua-regia and 1.5 mL H2O2 at 270°C for 3 h, respectively.

RESULTS

The mean metal concentration (μg/g dry weight basis) ranged in the ginger and soil samples, respectively, were: Ca (2000-2540, 1770-3580), Mg (2700-4090, 1460-2440), Fe (41.8-89.0, 21700-46900), Zn (38.5-55.2, 255-412), Cu (1.1-4.8, 3.80-33.9), Co (2.0-7.6, 48.5-159), Cr (6.0-10.8, 110-163), Mn (184-401, 1760-6470), Ni (5.6-8.4, 14.1-79.3) and Cd (0.38-0.97, 0.24-1.1). The toxic metal Pb was not detected in both the ginger and soil samples.

CONCLUSION

There was good correlation between some metals in ginger and soil samples while poor correlation between other metals (Fe, Ni, Cu). This study revealed that Ethiopian gingers are good source of essential metals and free from toxic metal Pb while containing negligible amount of Cd.

Levels of major and trace elements in fennel (Foeniculum vulgari Mill.) fruits cultivated in Ethiopia

Background

Sweet fennel (Foeniculum vulgare Mill.) is one of the precious spices. Almost all parts of fennel plant are edible. The herb is used as carminative, digestive, diuretic, cosmetic and medicine.

Methods

A 0.5 g of the oven dried fennel fruit and soil samples were digested by wet-digestion method. The levels of selected elements (Ca, Mg, Fe, Mn, Cu, Cr, Co, Zn, Ni, Cd and Pb) were determined in sweet fennel fruit (Foeniculum vulgari Mill.) and soil from Addis Ababa (Central Ethiopia) and Gojjam (Northern West Ethiopia) by flame atomic absorption spectrometry (FAAS).

Results

The elemental concentrations (μg/g) in fennel fruit were: Ca (20,500–23,000), Mg (1,310–3,460), Fe (1,140–1,900), Mn (31–51), Cu (24–103), Cr (91–98), Co (26–71), Zn (37–45), Ni (19–24), and Cd (1.6–1.9) while in the soil were: Ca (1,440–1,780), Mg (1,260–3,310), Fe (26,900–28,000), Mn (1,460–1,980), Cu (51–101), Cr (127–141), Co (54–143), Zn (99–104), Ni (98–161), and Cd (1.7–2.9). Pb was below the method detection limit in both the fennel fruit and soil.

Conclusion

The Ethiopian fennel fruits are rich in Ca and Mg and other essential elements (Fe, Cu, Co and Zn) and can be used as good supplement for human being in particularly for children and pregnant women. The toxic element Cd is at trace level and Pb is not detected in the fennel fruit. Thus, Ethiopian fennel fruits are safe for human consumption.

Comparative analysis of dry ashing and wet digestion methods for the determination of trace and heavy metals in food samples

This study compared the dry ashing and wet digestion methods of processing food samples for elemental analysis. The concentrations of trace elements (manganese, iron, copper and zinc) and heavy metals (chromium, cadmium, lead and nickel) were determined in varieties of samples classified as fruits, leafy and fruity vegetables, tubers, legumes and cereals, obtained from Abeokuta, South-West, Nigeria. The metal concentrations were determined using atomic absorption spectrophotometer according to standard methods. The accuracy of the procedures was confirmed by spiking some samples and evaluating their recoveries. The metal levels evaluated were relatively higher in the dry-ashed samples than the wet-digested samples. However, the results showed non-significant differences in most data obtained after processing with the two methods. The dry ashing method is recommended for digestion of food items in these categories because: it involves lesser amount of chemical reagents and related hazards; it requires simple equipment and achieved better recovery.

Concentrations of Mn, Fe, Cu, Zn, Cr, Cd, Pb, Ni in selected Nigerian tubers, legumes and cereals and estimates of the adult daily intakes

This study was designed to determine the levels of microminerals (manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), chromium (Cr)) and heavy metals (cadmium (Cd), lead (Pb) and nickel (Ni)) in some tubers, legumes and cereals obtained from the markets in Abeokuta city, South-West Nigeria. The food samples were digested by dry ashing procedure and their minerals were determined by atomic absorption spectrophotometer. The results show mean values of 1.67-32.00, 7.25-61.58, 1.59-10.56, 6.65-46.99, 0.02-0.58, <0.01-0.09, <0.08, and 0.06-0.14 mg/kg for Mn, Fe, Cu, Zn, Cr, Cd, Pb and Ni respectively. The levels of these metals in all the samples analysed were within the ranges reported for similar tubers, legumes and cereals from various parts of the world. The daily intakes of the metals through tubers, legumes and cereals were found to be lower than the provisional tolerable daily intakes proposed by Joint FAO/WHO Expert Committee on Food Additives.

Cadmium and lead in chocolates commercialized in Brazil

Cadmium (Cd) and lead (Pb) concentrations and their relationship to the cocoa content of chocolates commercialized in Brazil were evaluated by graphite furnace atomic absorption spectrometry (GF AAS) after microwave-assisted acid digestion. Several chemical modifiers were tested during method development, and analytical parameters, including the limits of detection and quantification as well as the accuracy and precision of the overall procedure, were assessed. The study examined 30 chocolate samples, and the concentrations of Cd and Pb were in the range of <1.7-107.6 and <21-138.4 ng/g, respectively. The results indicated that dark chocolates have higher concentrations of Cd and Pb than milk and white chocolates. Furthermore, samples with five different cocoa contents (ranging from 34 to 85%) from the same brand were analyzed, and linear correlations between the cocoa content and the concentrations of Cd (R(2) = 0.907) and Pb (R(2) = 0.955) were observed. The results showed that chocolate might be a significant source of Cd and Pb ingestion, particularly for children.

Blood concentration of copper, cadmium, zinc and lead in horses and its relation to hematological and biochemical parameters

Environmental pollution results in serious health hazards to animals and blood analysis serves as a good alternative for health status assessment. The target of this study was to analyze the concentration of selected metals in equine blood, to analyze the blood parameters and to find possible correlations. Blood samples were collected from the vena jugularis of healthy adult horses. The highest concentration of all elements was found in whole blood (Cu 3.84 ± 0.90 mg L(-1); Cd = 0.81 ± 0.90 mg L(-1); Zn 26.67 ± 14.12 mg L(-1); Pb 9.33 ± 5.76 mg L(-1)). Higher concentrations of copper, cadmium, zinc and lead were detected in blood clots compared to blood sera (44.04%). A similar tendency was found for cadmium (50%), zinc (13.08%) and lead (46.02%), which showed generally higher concentrations in blood clots (cells). Correlation analysis proved some relations between analyzed elements. In blood clots there is a strong positive correlation between Cd - Pb (r = 0.93) and Zn - Pb (r = 0.71) was detected. For biochemical and hematological parameters mainly medium correlations were detected. Obtained results prove different correlations of analyzed elements in blood components as well as the effect on parameters of blood biochemical and hematological profiles.