Method validation and determination of heavy metals in cocoa beans and cocoa products by microwave assisted digestion technique with inductively coupled plasma mass spectrometry

Rapid simultaneous quantification of arsenic and lead in grain using improved monochromatic excitation energy dispersive X-ray fluorescence spectrometry

In most cases, conventional energy dispersive X-ray fluorescence (EDXRF) analysis of trace arsenic (As) and lead (Pb) in grains encounters technical difficulties due to sensitivity challenges and the overlapping of characteristic X-ray lines. By utilizing high-definition X-ray technology and doubly curved crystal (DCC), along with establishing interference correction models for As and Pb, we can significantly improve analytical sensitivity for specific portions of the spectrum while reducing interference. This study demonstrates that the improved monochromatic excitation energy dispersive X-ray fluorescence spectrometry (MEDXRF), combined with an algorithmic analysis of fundamental parameters (FP), exhibits higher sensitivity compared to existing EDXRF methods. This improvement is achieved by optimizing the DCC structure, device geometry layout, and detection conditions. The detection limits, precision, and accuracy of MEDXRF for As and Pb were evaluated using certified reference materials (CRMs) and actual grain samples. The test results indicate that the limits of detection (LODs) were generally better than those specified by the Codex general standard, with values of 0.02 mg/kg for As and 0.03 mg/kg for Pb. The accuracy and precision were in good agreement with ICP-MS results. Therefore, the enhanced MEDXRF method offers sufficient sensitivity, accuracy and stability for the direct determination of As and Pb in grains below food safety limits.

Assessing blood metal levels in house sparrows (Passer domesticus) across urban and rural habitats in Meknes

This study investigates the concentration of heavy metals lead (Pb), cadmium (Cd), and zinc (Zn) in the blood of house sparrows (Passer domesticus) across various urban habitats in Meknes, Morocco. Fifty adult sparrows were captured from five distinct sites, including industrial, high-traffic, and rural areas. Blood samples were specifically analyzed for Pb, Cd, and Zn using Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES). Significant variations in metal concentrations were observed across the different sites, with the highest levels found in the industrial zone: lead (Pb) at 336.02 µg/L, cadmium (Cd) at 12.28 µg/L, and zinc (Zn) at 1736.09 µg/L. Principal component analysis (PCA) and K-means clustering identified three distinct pollution clusters: Cluster 0 (high Zn, low Pb and Cd), Cluster 1 (moderate levels of all metals), and Cluster 2 (high levels of all metals). These findings emphasize the ecological and health risks posed by urban pollution, and demonstrate the value of house sparrows as effective bioindicators.

Impact of Chocolate Cadmium on Vulnerable Populations in Serbia

Chocolate is one of the most popular and widely consumed confectionery products. However, elevated cadmium (Cd) content in this commodity threatens food safety and human health. It is crucial to monitor the presence of Cd in chocolate and to evaluate its associated health risks. This study assessed the Cd levels in milk and dark chocolates from the Serbian market (n = 155). Cadmium concentrations varied between 0.010 and 0.29 mg/kg. The obtained values were used to evaluate the hazard quotient (HQ) and cancer risk (CR). The estimated weekly intakes (EWIs) were below the tolerable limits for all samples. However, in some samples, the EWI reached 60.9% and 63.5% of the tolerable limit for toddlers and other children, respectively. No health risk was found based on the HQ. On the other hand, based on CR values, all chocolate products can be classified as posing a moderate risk. The Monte Carlo simulation indicated that toddlers and other children were more exposed to non-carcinogenic risk, whereas vegetarians, adults, pregnant women, and other children were more exposed to cancer risk. Sensitivity analysis indicates that body weight, exposure frequency, and ingestion rate are the most influential factors for non-cancer and cancer health risks.

Uptake and in-vitro bioaccessibility of toxic metals in cocoa beans: Human health risks

Cocoa-growing areas in Ghana have experienced a rise in mining activities affecting cocoa cultivation and increased concentrations of potentially toxic metals in the soil, which can accumulate in cocoa beans. This study evaluated potential toxic metal contamination in cocoa beans and soils from cocoa farms in mining and non-mining areas in Ghana. We used X-ray fluorescence and an ICP-MS to determine metal concentrations, and a Zeeman mercury analyzer to determine mercury. The farm soils exhibited a pH range of 4.08 - 6.86, electrical conductivity between 29.16 and 870.50 μS/cm, and soil organic matter content ranging from 4.78 to 7.38%. Generally, metal concentrations in the soil were within the Canadian Soil Quality Guidelines for Agricultural soils, Dutch Target and Intervention Values, and the world average world soil for unpolluted soils but varied between study areas. Arsenic (1.20 - 1.33 mg/kg), cadmium (2.68 - 3.16 mg/kg), chromium (9.31-11.73 mg/kg), copper (59.69-70.88 mg/kg), mercury (0.008-0.017 mg/kg), manganese (18.90-23.68 mg/kg), nickel (10.19-11.76 mg/kg), lead (1.71-1.86 mg/kg), and zinc (80.20-87.34 mg/kg) were found in cocoa beans. The mean bioaccessibility for metals in cocoa beans, except for As, Cu, and Pb, was greater than 60%. Cadmium had high contamination in soil; geoaccumulation (Igeo > 3), contamination factor (CF > 18), and enrichment factor (EF > 70.21), while Cu and Zn had high bioaccumulation (BF > 4). The target hazard quotient value for metals in all farms showed no potential health risk (THQ < 1) for both children and adult consumers. The cocoa beans produced have low risk upon consumption.

Novel Ternary System for Electrochemiluminescence Biosensor and Application toward Pb2+ Assay

This study constructed an electrochemiluminescence (ECL) biosensor for ultrasensitive detection of Pb2+ in a ternary system by employing DNAzyme. The ternary system is composed of a potassium-neutralized perylene derivative (K4PTC) as the ECL emitter, K2S2O8 as the coreactant, and neodymium metal-organic frameworks (Nd-MOFs) as the coreaction accelerators. Nd-MOFs immobilize DNAzymes and enhance the luminescence intensity of the K4PTC/K2S2O8 system. As part of this system, K4PTC enhances the ECL signal in solution and supports Pb2+ detection. The sequence of ferrocene (Fc)-linked DNA (DNA-Fc) is catalytically cleaved by DNAzymes in the presence of Pb2+. This causes the removal of DNA1-Fc from the electrode surface to recover the ECL signal. As a result, the as-prepared ECL biosensor can quantify Pb2+ with a detection limit (LOD) of 4.1 fM in the range of 1 μM to 10 fM. The ECL biosensor displays high specificity, good stability, excellent reproducibility, and desirable practicality for Pb2+ detection in tap water. Moreover, by simply changing the sequence of the DNAzyme, new biosensors can be designed for ultrasensitive detection of different heavy metal ions, offering an excellent approach for monitoring water quality safety.

Advancing Analytical Techniques in PET and rPET: Development of an ICP-MS Method for the Analysis of Trace Metals and Rare Earth Elements

Despite the extensive use of recycled polyethylene terephthalate (rPET) in food contact materials (FCMs), research on the presence of heavy metals (HMs) and rare earth elements (REEs) during various recycling stages (e.g., flakes, granules, and preforms) remains limited. This study aimed to address these gaps by validating a rapid and sensitive analytical method to quantify 26 HMs and 4 REEs in PET and rPET matrices. An ICP-MS method was validated per EURACHEM guidelines, assessing linearity, limits of detection (LOD), limits of quantification (LOQ), accuracy, and repeatability. The method was employed for initial screening of HMs and REEs classified as non-intentionally added substances (NIASs) in PET and rPET samples. The findings showed high accuracy and reliability, with recovery rates between 80% and 120%. Analysis revealed varying concentrations of HMs and REEs, with the highest levels in 100% rPET preforms, notably Zn, Cu, and Al among HMs, and La among REEs. The study identified critical contamination points during the recycling process, highlighting the need for targeted interventions. This research provides a crucial analytical framework for assessing HMs and REEs in PET and rPET, ensuring FCM safety compliance and supporting efforts to enhance rPET product safety, promoting public health protection and advancing the circular economy.

Electrochemical and statistical study of Nickel ion assessment in daily children intake samples relying on magnesium aluminate spinel nanoparticles

Lately, children's daily consumption of some products, such as cereals and candies, has been rising, which provides a compelling rationale for determining any metallic substances that may be present. Monitoring the concentration of certain metals, like nickel, in these products is necessary due to medical issues in humans when consumed regularly. So, in this work, a novel and highly selective carbon paste as a Ni(II) ion-selective sensor was prepared and investigated using ceramic magnesium aluminum spinel nanoparticles as the ionophore and tritolyl phosphate (TOCP) as a plasticizer. A modified co-precipitation method was used to synthesize the spinel nanoparticles. X-ray diffraction, scanning electron microscope with EDAX, transmission electron microscope, and BET surface area were used to determine the phase composition, microstructure, pores size, particle size, and surface area of the synthesized nanoparticles. The spinel nanoparticle was found to have a nano crystallite size with a cubic crystal system, a particle size ranging from 17.2 to 51.52 nm, mesoporous nature (average pore size = 8.72 nm), and a large surface area (61.75 m2/g). The composition ratio of graphite carbon as a base: TOCP as binder: spinal as ionophore was 67.3:30.0:2.7 (wt%) based on potentiometric detections over concentrations from 5.0 × 10-8 to 1.0 × 10-2 mol L-1 with LOD of 5.0 × 10-8 mol L-1. A measurement of 29.22 ± 0.12 mV decade-1 over pH 2.0-7.0 was made for the Nernstian slope. This sensor demonstrated good repeatability over nine weeks and a rapid response of 8 s. A good selectivity was shown for Ni(II) ions across many interferents, tri-, di-, and monovalent cations. The Ni(II) content in spiked real samples, including cocaine, sweets, coca, chocolate, carbonated drinks, cereals, and packages, were measured. The results obtained indicated no significant difference between the proposed potentiometric method and the officially reported ICP method according to the F- and t-test data. In addition to utilizing ANOVA statistical analysis, validation procedures have been implemented, and the results exceed the ICP-MS methodology.

A target-triggered ultra-sensitive aptasensor for simultaneous detection of Cd2+ and Hg2+ using MWCNTs-Au NPs modified electrode

A sensitive electrochemical assay for simultaneously detecting cadmium ion (Cd2+) and mercury ion (Hg2+) with the aptamer as recognition unit was established, in which methylene blue (MB) and target-triggered in-situ generated Ag nanoclusters (Ag NCs) were identified as signal reporters. Multi-walled carbon nanotubes and gold nanoparticles composites were prepared with polyethyleneimine to amplify electrical signals of screen-printed electrodes. Due to the particular base sequences, MB labeled Cd2+ aptamer paired with ssDNA through T-Hg-T structure with Hg2+. Notably, the C-rich structure in ssDNA acted as a template for the generation of Ag NCs, which could induce differential pulse voltammetry signals corresponding to Hg2+ concentrations. This electrochemical aptasensor exhibited detection limits of 94.01 pg/mL and 15.74 pg/mL for Cd2+ and Hg2+, respectively. The developed aptasensor allowed for practical application to tea and vegetable samples with satisfactory accuracy. This work possesses potential in developing biosensing technologies for simultaneous determination of multiple heavy metals.

Probabilistic health risk assessment of heavy metals (Cd, Pb, and As) in Cocoa powder (Theobroma cacao) in Tehran, Iran market

The concentrations of toxic elements were analyzed by using Flame Atomic Absorption Spectrophotometer (FAAS). Moreover, the human health risk was estimated by Total Target Hazard Quotient (TTHQ) and Cancer Risk (CR) in Monte Carlo Simulation (MCS) technique. The mean concentrations (mg/kg) of Cd (0.08 ± 0.08), Pb (0.23 ± 0.46), and As (0.06 ± 0.04), were in a good compliance with ISO (Iranian standard organization). TTHQ for adults and children was equal to 0.009 and 0.042, respectively and also mean CR in adults and children consumers was equal to 9.73E-7 and 9.08E-7, respectively. Consequently, the concentration of toxic elements (Cd, Pb, and As) in cocoa powder did not pose any safety concerns. Moreover, probabilistic health risk assessment revealed that both adults and children were not at considerable non-carcinogenic (THQ and/or TTHQ ≤ 1) and carcinogenic risk (CR ≤ 1E-6). Even though, seeking for mitigating solutions and applying them to suppress the dangers of food containing toxic elements is a critical subject.

Electrochemical and Colorimetric Nanosensors for Detection of Heavy Metal Ions: A Review

Human exposure to acute and chronic levels of heavy metal ions are linked with various health issues, including reduced children's intelligence quotients, developmental challenges, cancers, hypertension, immune system compromises, cytotoxicity, oxidative cellular damage, and neurological disorders, among other health challenges. The potential environmental HMI contaminations, the biomagnification of heavy metal ions along food chains, and the associated risk factors of heavy metal ions on public health safety are a global concern of top priority. Hence, developing low-cost analytical protocols capable of rapid, selective, sensitive, and accurate detection of heavy metal ions in environmental samples and consumable products is of global public health interest. Conventional flame atomic absorption spectroscopy, graphite furnace atomic absorption spectroscopy, atomic emission spectroscopy, inductively coupled plasma-optical emission spectroscopy, inductively coupled plasma-mass spectroscopy, X-ray diffractometry, and X-ray fluorescence have been well-developed for HMIs and trace element analysis with excellent but varying degrees of sensitivity, selectivity, and accuracy. In addition to high instrumental running and maintenance costs and specialized personnel training, these instruments are not portable, limiting their practicality for on-demand, in situ, field study, or point-of-need HMI detection. Increases in the use of electrochemical and colorimetric techniques for heavy metal ion detections arise because of portable instrumentation, high sensitivity and selectivity, cost-effectiveness, small size requirements, rapidity, and visual detection of colorimetric nanosensors that facilitate on-demand, in situ, and field heavy metal ion detections. This review highlights the new approach to low-cost, rapid, selective, sensitive, and accurate detection of heavy metal ions in ecosystems (soil, water, air) and consumable products. Specifically, the review highlights low-cost, portable, and recent advances in smartphone-operated screen-printed electrodes (SPEs), plastic chip SPES, and carbon fiber paper-based nanosensors for environmental heavy metal ion detection. In addition, the review highlights recent advances in colorimetric nanosensors for heavy metal ion detection requirements. The review provides the advantages of electrochemical and optical nanosensors over the conventional methods of HMI analyses. The review further provides in-depth coverage of the detection of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) ions in the ecosystem, with emphasis on environmental and biological samples. In addition, the review discusses the advantages and challenges of the current electrochemical and colorimetric nanosensors protocol for heavy metal ion detection. It provides insight into the future directions in the use of the electrochemical and colorimetric nanosensors protocol for heavy metal ion detection.

Determination of copper(II) and lead(II) ions in dairy products by an efficient and green method of heat-induced homogeneous liquid-liquid microextraction based on a deep eutectic solvent

In this study, a new homogeneous liquid-liquid microextraction method using a deep eutectic solvent has been developed for the extraction of Cu(II) and Pb(II) ions in dairy products. Initially, the deep eutectic solvent was synthesized using choline chloride and p-chlorophenol and used as the extraction solvent. The synthesized solvent was soluble in milk at 70 °C and its separation from the sample was performed by decreasing the temperature. By cooling, a cloudy solution was formed due to the low solubility of the solvent at low temperatures. On centrifugation, the fine droplets of the solvent containing the analytes settled at the bottom of the tube by sedimentation. The enriched analytes were determined by flame atomic absorption spectrometry. The effect of some important parameters such as the amount of protein precipitating agent , complexing agent amount, extraction solvent volume, salt addition, pH, and temperature on the extraction efficiency of the method was studied and optimized. Under the optimal conditions, the linear ranges of the method for Cu(II) and Pb(II) ions were obtained in the ranges of 0.10-50 and 0.50-50 μg L-1 with detection limits of 0.04 and 0.18 μg L-1, respectively. The repeatability of the developed method, expressed as relative standard deviation, was determined to be 3.2 and 3.9% for Cu(II) and Pb(II) ions, respectively. Finally, by determining the concentration of Cu(II) and Pb(II) ions in milk, doogh, and cheese samples, the feasibility of the method was successfully confirmed with the extraction recoveries of 95.9 and 92.1% for Cu(II) and Pb(II) ions, respectively.

The concentration of potentially toxic elements (PTEs) in Iranian rice: a dietary health risk assessment study

In the present study, six potentially toxic elements (PTEs), including chromium (Cr), arsenic (As), cadmium (Cd), lead (Pb), copper (Cu), and nickel (Ni), were determined in 41 domestic rice samples collected from Tehran using ICP-OES (inductively coupled plasma-optical emission spectrometry). The mean concentration of Cd, As, Cu, Pb, Cr, and Ni was found as 0.014 ± 0.01, 0.018 ± 0.005, 2.15 ± 1.84, 0.42 ± 0.31, 0.1 ± 0.16, and 0.48 ± 0.36 mg kg-1, respectively. Possible risks due to ingestion of PTEs via rice consumption for children and adults were assessed by Monte Carlo simulation. The 50th percentile of estimated Cr intake for children through domestic rice consumption exceeded the maximum tolerable daily intake. There was only a potential non-carcinogenic risk for single Cr exposure for children. The 95th percentile of the estimated hazard index (HI) for children and adults was 4.34 and 1.05, indicating a potential non-carcinogenic risk related to multiple PTE exposure. The lifetime cancer risk (ILCR) values derived from Cr, Ni, As, and Cd exposure exceeded the threshold value, indicating a carcinogenic risk due to PTEs' exposure. The deterministic assessment demonstrates that the Tehran population may be at risk through domestic rice consumption. This study indicates that risk related to the exposure to multiple PTEs through the consumption of rice in adults and children in Tehran is recognized as an important issue, thus supporting the importance of cumulative analysis of the risk of exposure to PTEs through food. Finally, national strategic environmental assessment and technological solutions for monitoring and protecting freshwater, soil, waste management, and chemicals as a global concern policy are needed for public health.

Biosorption potential of viable and dead Aspergillus flavus biomass on polluted pond water

The State Industries Promotion Corporation of Tamil Nadu Ltd (SIPCOT) Lake is never dry; it is always full of water and was recently used as a waste reservoir by the native peoples and industrialists. Thus, this investigation was performed to assess the quality of the lake water and evaluate the possible biosorption potential of Aspergillus flavus on this lake water sample through batch model biosorption study. The water quality parameters analyses revealed that the lake water has been polluted with number of contaminates which including organic and inorganic. The most of the parameters such as pH (9.5 ± 0.7), turbidity (38 ± 1.1 NT unit), TDS (2350.12 ± 31.24 mg L^-1), BOD (40.21 ± 3.27 mg L^-1), and COD (278.61 ± 11.84 mg L^-1), Ca (212.85 ± 9.64 mg L^-1), Fe (3.1 ± 0.8 mg L^-1), NH₃ (15.62 ± 0.5 mg L^-1), NO_3-(5.84 ± 0.14 mg L^-1), Cl^- (1257.85 ± 4.6 mg L^-1),Cd (15.64 ± 0.29 mg L^-1), Cr (6.86 ± 0.34 mg L^-1), Pb (25.61 ± 3.41 mg L^-1), and Hg (1.8 ± 0.024 mg L^-1) content of water sample were beyond the acceptable limits. Fortunately, the A. flavus dead biomass showed considerable biosorption potential (Cd: 27.5 ± 1.1%, Cr: 13.48 ± 1.2%, Pb: 21.27 ± 1.5%, and Hg: 6.49 ± 0.86% in 180 min of contact time) than viable form on polluted lake water. Since, reduced the quantities of most of the parameters which beyond the permissible limit and also increased remarkable percentage of DO in the water sample in a short period of contact time. These findings suggest that A. flavus dead biomass can be used for bioremediation of polluted water in a sustainable manner.

Ganoderma lucidum bran-derived blue-emissive and green-emissive carbon dots for detection of copper ions

Ganoderma lucidum bran (GB) has a broad application prospect in the preparation of activated carbon, livestock feed, and biogas, but the preparation of carbon dots (CDs) from GB has never been reported. In this work, GB was applied as a carbon source and nitrogen source to prepare both blue fluorescent CDs (BCDs) and green fluorescent CDs (GCDs). The former were prepared at 160 °C for 4 h by a hydrothermal approach, while the latter were acquired at 25 °C for 24 h by chemical oxidation. Two kinds of as-synthesized CDs exhibited unique excitation-dependent fluorescence behavior and high fluorescent chemical stability. Based on the fantastic optical behavior of the CDs, they were utilized as probes for fluorescent determination of copper ions (Cu²⁺). In the range of 1-10 μmol L^-1, the fluorescent intensity of BCDs and GCDs decreased linearly with the increase of Cu²⁺ concentration; the linear correlation coefficient reached 0.9951 and 0.9982, and the limit of detection (LOD) was 0.74 and 1.08 μmol L^-1, respectively. In addition, these CDs remained stable in 0.001-0.1 mmol L^-1 salt solutions; BCDs were more stable in the neutral pH range, but GCDs were more stable in neutral to alkaline conditions. The CDs prepared from GB are not only simple and low-cost, but also can realize the comprehensive utilization of biomass.

Multidimensional analysis of the essential elements in pregnant women's whole blood and characterization of maternal status by elemental pattern

BACKGROUND

During pregnancy, the fetus needs to obtain a lot of nutrients from the mother, but the micronutrient deficiencies in pregnancy are not clear at present, and there is no reliable basis for nutrient intake and supplement. The purpose of this study was to understand the levels of essential elements in whole blood of pregnant women during various pregnancy stages at different ages and in different regions, to evaluate the deficiency of essential elements in Chinese pregnant women, and to explore the feasibility of using the elemental pattern to characterize maternal status.

METHODS

Whole blood samples of 11222 healthy pregnant women enrolled in different areas of China from Jan-Dec 2019, were analyzed for concentrations of six essential elements including Mn, Cu, Zn, Ca, Mg, and Fe, using the inductively coupled plasma mass spectrometer. A retrospective comparative study during different pregnancy periods at different ages and in different regions in whole blood essential elements content from non-pregnant normal women and pregnant normal women was developed using multivariate statistical analysis. Principal component analysis evaluation elemental pattern was used to characterize pregnancy status of pregnant women.

RESULTS

In general, the levels of six essential elements in whole blood of pregnant women can satisfy the needs of normal physiological activities. With the development of pregnancy, the contents of Cu and Mn increased, while the contents of Fe and Mg decreased, and the contents of Zn and Ca have no noteworthy change. At the same gestation stage, the Cu content in whole blood of elderly pregnant women was higher. There were some differences in whole blood essential elements content of pregnant women in different regions. Principal component analysis and heat map analysis showed the feasibility of using bioinformatics research strategies to identify different pregnancies.

CONCLUSIONS

There are differences in the content of whole blood essential elements of women at different stages of pregnancy in different regions. It was found that there was no obvious deficiency in whole blood essential elements levels of pregnant women in recent years. The pattern of essential elements has a certain application potential in the evaluation of pregnancy and pregnant women's health status.

An Evaluation of Different Digestion Methods for the Quantitation of Inorganic Elements in Human Hair Using ICP-MS

The inorganic elements have unique properties in biochemical processes in humans. An increasing number of pathologies have been associated with essential element ions, such as lead, mercury, and cadmium. Hair has become an attractive clinical specimen for studying the longitudinal exposure to elements from the external environment. Inductively coupled plasma-mass spectrometry (ICP-MS) coupled with nitric acid (HNO₃) digestion is the most common approach for determining inorganic elements from human hair. This study aims to optimize the digestion method for the absolute quantitation of 52 elements using ICP-MS, for a large cohort study in human hair. Five different HNO₃ (65%) digestion methods were investigated and evaluated for their internal standard solution stability, reproducibility, element coverage, and standard solution recovery efficiency, namely, room temperature for 24 h (RT), 90°C for 4 h (T90), ultrasonic-assisted digestion (UltraS), programmed digestion of microwave digestion (MicroD), and ordinary microwave oven digestion (O-MicroD). Our results demonstrated that O-MicroD, MicroD, and RT were the best performing digestion methods for coefficient of variation (CV) scores, coverage, and recovery efficiency, respectively. In particular, the O-MicroD method detected multiple elements in a small quantity of hair (3 mg), with minimum nitric acid usage (200 μl) and a short digestion time (30 min). The O-MicroD method had excellent reproducibility, as demonstrated by a continuous thousand injections of hair samples with three internal standards (CV: ¹⁰³Rh = 3.59%, ¹¹⁵In = 3.61%, and ²⁰⁹Bi = 6.31%). Future studies of the elemental content of hair should carefully select their digestion method to meet the primary purpose of their study.

Risk Assessment and Determination of Heavy Metals in Home Meal Replacement Products by Using Inductively Coupled Plasma Mass Spectrometry and Direct Mercury Analyzer

This study quantified six heavy metals (Pb, Cd, As, Sn, Hg, and Me-Hg) in home meal replacement products. Satisfactory linearity (R2 > 0.99), recovery (80.65–118.02%), limits of detection (0.02–2.81 μg/kg), limits of quantification (0.05–8.51 μg/kg), accuracy (80.49–119.87%), precision (0.26–14.93%), standard uncertainty (0.082–0.321%) and relative standard uncertainty (0.084–0.320%) of the six heavy metals were obtained. The average concentration of the six heavy metals was 8.87 μg/kg. Heavy metal concentrations were converted to food intake data of 0.009 μg/kg to recalculate the 95th percentile food intake data (g/day) of individual heavy metals. These were then divided by age group to evaluate the average exposure to heavy metals and determine the 95th percentile of exposure from daily intake and for the whole population, of home meal replacement products. The chronic daily intake amount of six heavy metals was 1.60 × 10−2 μg/kg/day. Based on total chronic daily intake values, the risk and margin of exposure of each of the heavy metals was 9.13 × 107, demonstrating that intake associated with home meal replacement products is negligible.

Changes in Copper, Zinc, Arsenic, Mercury, and Lead Concentrations in Rat Biofluids and Tissues Induced by the "Renqing Changjue" Pill, a Traditional Tibetan Medicine

The "Renqing Changjue" pill (RQCJ), as an effective prescription of Traditional Tibetan Medicine (TTM), has been widely used in treating advanced gastroenteropathy diseases for over a thousand years. However, the toxicity and adverse effects of TTM have attracted increasing attention because heavy metals may be added as active ingredients. In this work, we introduced a robust model based on endogenous metabolism enabling the study of changes in copper (Cu), zinc (Zn), arsenic (As), mercury (Hg), and lead (Pb) concentrations and the mechanism between biofluids (blood and urine) and tissue (liver, kidney, spleen) samples from rats treated with RQCJ, along with metabolic changes after different treatment time points. Inductively coupled plasma-mass spectrometry was used to monitor the heavy metals. Slightly different trends of heavy metals were observed in rat metabolites. The levels of Hg, As, and Pb were clearly dose-dependent in the tissue and biofluid samples. Basic recovery of Hg and Pb was found after stopping treatment with RQCJ. The accumulation of As was more obvious in the blood, liver, kidney, and spleen; however, Hg was deposited in the kidney. Pb accumulated the most in the spleen. The concentrations of Cu and Zn were constant or accumulated to a certain extent, which could cause the body to have Cu and Zn metabolism disorders in the administration period. Our findings highlight how metal changes and effects on the mechanisms might contribute to the progression of understanding of the toxicity information for RQCJ. Therefore, precautions should be taken in the clinic to monitor the potential toxicity of RQCJ with long-term administration.

Quality differentiation of cocoa beans: implications for geographical indications

Geographical indications may stimulate collective actions of governance for quality control, trade and marketing as well as innovation based on the use of local resources and regional biodiversity. Cocoa production, however, dominated by small family agriculture in tropical regions, has rarely made use of such strategies. This review is aimed at understanding major research interests and emerging technologies helpful for the origin differentiation of cocoa quality. Results from literature search and cited references of publications on cocoa research were imported into VOSviewer for data analysis, which aided in visualizing major research hotpots. Co-occurrence analysis yielded major research clusters which guided the discussion of this review. Observed was a consensus recognizing cocoa quality resulting from the interaction of genotype, fermentation variables and geographical origin. A classic view of cocoa genetics based on the dichotomy of 'fine versus bulk' has been reexamined by a broader perspective of human selection and cocoa genotype evolution. This new approach to cocoa genetic diversity, together with the understanding of complex microbiome interactions through fermentation, as well as quality reproducibility challenged by geographical conditions, have demonstrated the importance of terroir in the production of special attributes. Cocoa growing communities around the tropics have been clearly enabled by new omics and chemometrics to systematize producing conditions and practices in the designation of specifications for the differentiation of origin quality. © 2021 Society of Chemical Industry.

Comprehensive strategy for pesticide residue analysis in cocoa beans through qualitative and quantitative approach

Multiresidue quantitative and qualitative screening method for the analysis of pesticide residues in dried cocoa beans was validated and applied to imported and domestic cocoa beans samples. The quantitative method comprises of 15 pesticides while the screening method covers 110 pesticides of different chemical classes. The method was based on modified QuEChERS (Quick Easy Cheap Efficient Rugged Safe) extraction and detection using triple quadrupole (QQQ-MS) and ion mobility quadrupole time of flight mass spectrometry (IMS-QTOF). The method was quantitatively validated in terms of linearity, limit of quantification (LOQ), specificity, selectivity, accuracy, and precision. On the other hand, screening detection limits were established for 110 pesticides. Finally, the optimized strategy was successfully applied for the routine analysis of pesticide residues in 137 cocoa bean samples and 32% of the total samples were found positive for ametryn, chlorpyrifos, isoprocarb, and metalaxyl.

Health and exposure risk assessment of heavy metals in rainwater samples from selected locations in Rivers State, Nigeria

Rainwater has being getting popularity in use due to lack of portable water sources in Nigeria. The study seeks to evaluate the health and exposure risk assessment of heavy metals from the usage of rainwater from inhabitants of four oil producing area of Rivers State, Nigeria. A total of 32 rainwater samples were collected from different sampling surfaces (ambient, zinc, aluminium, asbestos and stone-coated) to analyse for arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), mercury (Hg), lead (Pb) and zinc (Zn) using inductively coupled plasma – optical emission spectrophotometer. Analysed concentration (mg/L) showed varying results across different sampling surfaces converted to average concentration (mg/kg) was below WHO/FAO recommended guideline with no issue associated. Health and Exposure risk assessment were performed on analysed results from rainwater samples as non-carcinogenic risk assessment showed that HI value is less than 1.0 indicating no risk to population who consumes rainwater across different roofing surfaces in Rivers state. Carcinogenic risk assessment showed that chromium-VI were found to be the highest contributor to cancer risk across all sampling surfaces. Special treatment and regulations should be taken into consideration especially on stone-coated roof before administering to children, as they are prone to health issues due to developing immunity compared to adults.

A novel smartphone-based electrochemical cell sensor for evaluating the toxicity of heavy metal ions Cd2+, Hg2+, and Pb2+ in rice

A novel smartphone-based electrochemical cell sensor was developed to evaluate the toxicity of heavy metal ions, such as cadmium (Cd²⁺), lead (Pb²⁺), and mercury (Hg²⁺) ions on Hep G2 cells. The cell sensor was fabricated with reduced graphene oxide (RGO)/molybdenum sulfide (MoS₂) composites to greatly improve the biological adaptability and amplify the electrochemical signals. Differential pulse voltammetry (DPV) was employed to measure the electrical signals induced by the toxicity of heavy metal ions. The results showed that Cd²⁺, Hg²⁺, and Pb²⁺ significantly reduced the viability of Hep G2 cells in a dose-dependent manner. The IC₅₀ values obtained by this method were 49.83, 36.94, and 733.90 μM, respectively. A synergistic effect was observed between Cd²⁺ and Pb²⁺ and between Hg²⁺ and Pb²⁺, and an antagonistic effect was observed between Cd²⁺ and Hg²⁺, and an antagonistic effect at low doses and an additive effect at high doses were found in the ternary mixtures of Cd²⁺, Hg²⁺, and Pb²⁺. These electrochemical results were confirmed via MTT assay, SEM and TEM observation, and flow cytometry. Therefore, this new electrochemical cell sensor provided a more convenient, sensitive, and flexible toxicity assessment strategy than traditional cytotoxicity assessment methods.

Simultaneous determination of cadmium, lead and copper in chocolate samples by square wave anodic stripping voltammetry

In this work, an effective and simple method is proposed for the simultaneous determination of cadmium, lead and copper in chocolate samples by Square Wave Anodic Stripping Voltammetry (SWASV). An ultrasonic bath was used for the extraction of cadmium, lead and copper from fourteen chocolate samples using HNO₃ solution (7 mol L^-1). The electrochemical system consisted of a cell with three electrodes and HCl solution (10 mmol L^-1) as the supporting electrolyte. An efficient extraction of the metals (~100%) was attained after 1 h of ultrasonic pre-treatment. Quantitative analysis was carried out by the standard addition method. Good linearity, precision and accuracy were obtained in the range of concentrations examined. The accuracy was evaluated by means of a reference sample of spiked skim milk powder (BCR 151) to prove the reliability of the method. Detection limits (LOD) of 0.089, 0.059 and 0.018 µg g^-1 were found for cadmium, copper and lead, respectively, in the chocolate samples. Concentrations in chocolate samples were 4.30-138 µg g^-1 for Cu and 0.83-27.9 µg g^-1 for Pb, with no significant Cd. The simultaneous determination brings advantages to other methods already reported for chocolate analysis and the samples preparation proposed avoids the traditional sample mineralization step. These characteristics show this new method is especially attractive for case studies and routine analysis.

Investigation of chocolate types on the content of selected metals and non-metals determined by ICP-OES analytical technique

Chocolate, one of the most popular sweets in the world, is consumed by people of all ages. Available data point to significant increases in consumption and production. However, successful determination of elements in chocolate is still difficult because of the characteristics of the matrix which contains a high content of organic compounds, like hydrogenated vegetable oil, vegetable fats, solids from malt extract, salts, emulsifiers, etc., causing problems with appropriate decomposition or digestion of sample. In this study, chocolate samples were prepared according to two procedures: water bath and microwave-assisted mineralisation. The use of Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) allowed us to determine the elemental composition of dark, milk, and white chocolate bars available on the Polish market as well as a cacao sample (100% cocoa powder). The elements assessed were Al, Ba, Ca, Cu, Fe, K, Mg, Mn, Na, Ni, P, S, Sr, and Zn. The obtained results were used to compare the effectiveness of sample pre-treatment methods and to assess the correlation between the concentrations of specific elements and type of chocolate by the application of chemometric and statistical tools. The research showed that levels of analysed macro- and microelements are directly connected with the type of chocolate, characterised by the variable contents of cocoa paste and added milk. Data for all samples after mineralisation shown that among macroelements P was the most abundant, followed by Mg, Ca, Na, K, and S. The major essential element with the highest level was Fe, followed by Zn and Cu. In the group of toxic metals the highest content was obtained for Ba, then Al and Sr, but none exceeded permissible values prepared by health benefit organisations.