Determination Of Heavy Metals Research Articles

Determination of Heavy Metals in Two Common Street Foods (Falafel and Chiken Shoulder & Wing) Consumed in Qom City, Iran

Background & Aims: Street foods are ready-to-eat foods and drinks prepared and sold by vendors on the streets and other public places for immediate consumption or consumption at other times without any processing steps and are welcomed by a wide range of people for reasons such as the economy and easier access. This study aimed to investigate the status of heavy metals such as lead (Pb), cadmium (Cd), aluminum (Al), arsenic (As), and manganese (Mn) in the most common street foods in Qom City, Iran, (Falafel, shoulders and wings) according to the particular cultural, social, pilgrimage, and tourism conditions of the city. Materials and Methods: After preparing and collecting 18 samples of Falafel and 18 samples of shoulders and wings in the summer via quota stratified sampling method from supply and distribution centers in the city, the samples were transferred to the instrumental analysis laboratory of the faculty of health. After crushing, grinding, and weighing 2g of the samples, dry ashing was performed while maintaining the temperature program. White ash was dissolved in 5% nitric acid, and finally, the concentrations of Pb, Cd, As, Al, and Mn in the samples were measured by graphite furnace atomic absorption spectrometry (GFAAS). Results: According to this study, Mn, Al, and Pb metals had the highest concentrations in falafel, shoulder, and wing samples. Mean concentrations of Al, As, Cd, Pb and As in falafel samples were 10.07±9.82, 0.0005±0.0002, 0.0007±0.0003, 2.65±1.33, 24.50±11.91 µg/g, respectively, and in the shoulder & wing samples 11.12±7.70, 0.0009±0.0006, 0.050±0.018, 1.62±1.24, 18.50±14.64 µg/g, respectively. Also, the concentrations of Al, Pb, and Mn were higher than the standard level in all samples. The results showed that the mean concentration of As and Cd in Falafel, shoulder, and wing samples were less than the standard level. Conclusion: According to the results of this study, the concentration of aluminum, lead, and manganese in all samples is higher than the standard level; it seems that if the necessary hygienic measures are not taken during the various stages of production and supply of these foods, it will seriously threaten the health of consumers. The usefulness and enjoyment of street food are essential factors in encouraging consumers to purchase this type of food, so with the widespread acceptance of this type of food by society, essential strategies should be adopted by health authorities to create a proper food culture in society by emphasizing the correct understanding of food safety hazards and the quality of food consumed.

Preliminary Determination of Heavy Metals in Sediment, Water, and Some Macroinvertebrates in Tawi-Tawi Bay, Philippines

Determination of heavy metals is enormously important to determine the condition of the aquatic environment in terms of chemical pollution. In this study, a preliminary determination of heavy metal concentrations in sediment, water, and some macroinvertebrates in several sampling sites along Tawi-Tawi Bay, Philippines, was undertaken to have an initial status of heavy metal pollution in the area. Results revealed that the average concentration of heavy metals followed the order of Fe>Zn>Mn>Pb>Cu>Ni>Cd for sediment, Pb > Zn > Cu > Ni > Fe > Cd > Mn for seawater, Fe > Zn > Mn > Cu > Pb > Ni > Cd for spider conch (Lambis lambis Linnaeus, 1758), and Fe> Zn > Pb > Ni > Mn > Cu > Cd for sea cucumber (Holothuria scabra, Jaeger, 1833). However, all these determined heavy metals were within the safety limits set by WHO, US (EPA and FDA), and EMA. This study suggests that despite the anthropogenic activities in the coastal areas, heavy metal contamination in Tawi-Tawi Bay has not exceeded the safety limits.

Phytochemical and Pharmacognostical evaluation of an anti-inflammatory and Hapatoprotective poly-pharmaceutical preparation “Qurs-e-Zarishk”

Since the time Hippocrates man has made the use the different Unani medicines for the treatment of various ailments and still vast majority of population depends on these drugs. So the herbal drugs are gaining more and more attention all over the world due to their long historical clinical practice and less side effects. “Qurs- e- Zarishk” is one of the most important poly-pharmaceutical Unani formulation widely used for the treatment of liver disorders and anemia. Since the formulation has a very effective role in curing such diseases with zero side effects (unlike in Modern Medicine) so all the ingredients used in this preparation are required to be authenticated and standardized properly for quality control purposes. The present paper deals with different physicochemical and biological parameters like botanical identification, microbial load, aflatoxin, pesticide residue, determination of heavy metals, qualitative and quantitative analysis of phyto-chemical constituents, solubility in alcohol and water, successive extractions, pH values, ash values, quantitative estimation of total phenolics, resins etc. Besides, TLC studies of successive extracts have also been carried out.

Utilization of leather fibrous wastes for the production of reconstituted fibric materials: heavy metal determination and removal

Utilization of leather fibrous wastes for the production of reconstituted fibric materials: heavy metal determination and removal

Levels of three heavy metals in ground water and cereals in Chattogram Division, Bangladesh

Heavy metals determination in cereals and vegetables is one of the vital interests, because of their essential or toxic nature. In order to assess the levels and the impact of different toxic metals on human health, a study was carried out to determine the concentration of different toxic metals present in ground water and edible cereals (rice, wheat, and maize), which are grown in Chattogram area of Bangladesh. The concentrations of three heavy metals, Lead (Pb), Chromium (Cr) and Copper (Cu) in ground water and three varieties of cereals were determined by using Atomic Absorption Spectroscopy (AAS). Results on ground water showed that the mean concentrations of Pb content were within the permissible limits in terms of Bangladesh Drinking water standards, but exceeds the WHO Drinking Water Standards (WHODWS), US Environmental Protection Agency Drinking Water Standards (USEPADWS) values. However, Cr and Cu content were within the permissible limits in terms of Bangladesh Drinking water standards, WHODWS and USEPADWS values, respectively. The concentrations of Pb, Cr and Cu in rice ranged from 0.853 to 9.265mg/L, 0.096 to 0.475µg/L and 0.096 to 0.562mg/L; in wheat,from 0.363 to7.523 mg/L, 0.056 to 0.284 µg/L and 0.065 to 0.326 mg/L; in maize, from 0.739 to 8.372 mg/L, 0.058 to 0.248 µg/L and 0.036 to 0.478 mg/L, respectively. Thus, awareness should be raised among the people about the adverse health effects of these metals. The carcinogenic and non-carcinogenic risks of Pb, Cr and Cu for human health is a matter of concern

Determination of Heavy Metals, Arsenic, and Aluminum Content in Pumpkin Seed Herbal Substance and Native Products, by Inductively Coupled Plasma Mass Spectrometry

Pumpkin seeds belong to the so-called native products. Their characteristic feature is that they can be consumed directly, without prior extraction of the starting material. All elemental toxicants contained in pumpkin seeds are transferred in full to the native product. Therefore, it is important to study specific aspects of elemental toxicant accumulation by pumpkin seeds.The aim of the study was to determine the content of heavy metals, As, and Al in pumpkin seed herbal substance and native products, and to assess the degree of accumulation of these elements, depending on the vegetation area.Materials and methods: the study evaluated pumpkin seed native products by Russian manufacturers as well as pumpkin seeds harvested in areas with different anthropogenic load. The sample preparation was performed by microwave digestion, and the determination of the elemental toxicants was perfomed by inductively coupled plasma mass spectrometry.Results: the pumpkin seeds were shown to contain essential, probably essential, potentially toxic, and toxic elements. The authors performed comparative analysis of the elemental composition of pumpkin seeds as well as seeds, grains, and beans of various oil-bearing, grain, and leguminous crops.Conclusions: the content of the specified elemental toxicants (As, Cd, Hg, Pb) in the tested samples of pumpkin seed herbal substance and herbal medicinal products did not exceed the limits established by the Russian Pharmacopoeia. The unspecified toxic elements were either absent in pumpkin seeds (Tl) or found in trace amounts (Al). The content of a number of essential elements (Zn, Fe, Mn, Cu, Mo, Cr) in pumpkin seeds was higher than in the seeds of many oil-bearing crops. The vegetation area had no significant influence on the content of the tested elements in the pumpkin seeds. Pumpkin seeds are capable of accumulating abnormally high amounts of Cd, Co, and Ni in areas with high environmental pollution.

Monitoring The Content of Heavy Metals in The Soil and Wines from Different Wine-Growing Areas of Romania

Determination of heavy metals in soil and wine is very important for wine quality and consumer health, but at the same time it is a complementary tool for differentiating wines according to their geographical origin. In this work, soils and ten brands of wines originated from four major wine-growing areas of Romania (Iaşi, Babadag, Ştefăneşti and Blaj) were considered for performing a multielement (Cr, Ni, Cu, As, Pb, Hg, V, Sr, Mn, Zn, Fe) investigation in order to assess regional specificity. Heavy metals found in the investigated wines were below the limits imposed by European standards (O.I.V.) the elements concentrations following the trend: Zn>Fe>Mn>Sr>Ni>Cr>Cu>Pb>V>Hg>As. For the soils analyzed, the heavy metals content was found to be below the maximum permitted limit, except for Cu (135.45 mg/kg) from the Iaşi vineyard, which was at the permitted limit. The high values obtained for copper may be the result of different treatments with the Bordelaise solution for the vine. The elements CA, Mn and Hg observed from the research that they are predominantly of natural origin. Based on our results, a distinction has been made between wines according to their geographical origin, considering that the specific elements of discrimination Sr, Pb, and Ni for the Stefănesti vineyard (Muntenia region), Cr and Hg for the Babadag vineyard (Dobrogea region), Sr and V for the Iaşi vineyard (region of Moldova), respectively Fe and Zn for the Blaj vineyard (Transilvania region).

Determination of heavy metals in raw and pasteurized liquid milk of Bangladesh to assess the potential health risks

Milk is a balanced diet and the consumption of milk is increasing day by day in Bangladesh. For public health concerns, it becomes essential to detect the amount of heavy metals in milk and their effects on human health. For this purpose, the potential health risks of adults and children due to consumption of Cow raw milk and liquid Pasteurized milk were accessed. In this research, the concentrations of eight heavy metals namely Iron (Fe), Copper (Cu), Manganese (Mn), Zinc (Zn), Lead (Pb), Cadmium (Cd), Chromium (Cr) and Arsenic (As) in 64 samples of raw and liquid Pasteurized cow’s milk were accessed. These samples are collected from 64 different administrative areas of Bangladesh. From this study, it was found that Cu showed the highest concentration and daily intake rate; while Pb showed the lowest concentration and daily intake among these metals. Except for Cr, the value of estimated daily intake (EDI) of the heavy metals was found to be lower than the permissible value. From the results of EDI, it can be concluded that the minor potential health risks may occur due to the consumption of raw and liquid pasteurized milk samples. From Target Hazard Quotient (THQ) values, it can be said that there is no chance of non-carcinogenic health risks. From the Target Carcinogenic Risk (TCR) values of As and Pb, it could be suggested that child milk consumers are sensitive to be exposed to carcinogenic health risk.

Health Risk Assessment and Multivariate Statistical Analysis of Heavy Metals in Vegetables of Khyber Pakhtunkhwa Region, Pakistan.

The level of heavy metals in vegetables grown in soil irrigated with various sources of water and the health risks associated with the consumption of these vegetables were assessed in this study. Samples of water, soil, and vegetables were collected from farmer fields. After digestion in acidic solution, analytical measurements were made using an atomic absorption spectrophotometer. The mean concentration of Pb, Cr, Cd, Cu, Zn, Ni, Fe, and Mn in the soil of two sampling area were in the range from 60.00 to 84.00mgkg-1, 68.00 to 98.00mgkg-1, 1.60 to 2.60mgkg-1, 26.10 to 33.20mgkg-1, 22.60 to 30.80mgkg-1, 50.10 to 78.30mgkg-1, 420.00 to 471.00mgkg-1, and 270.20 to 340.50mgkg-1, respectively. Heavy metals in soil varied significantly at (P ≤ 0.001) among sampling area. The nine heavy metals were divided into two clusters for wastewater and soil, according to cluster analysis. The number of variables was reduced using principal component analysis, which yielded three latent factors, one for wastewater and one for soil. Pb, Cr, Cd, Cu, Zn, Ni, Fe, and Mn concentrations were significantly higher at P ≤ 0.001 in nine vegetables grown on soil irrigated with untreated wastewater than in vegetables grown on fresh-tube well-water-irrigated soil. The health risks associated with metal intake were assessed using the estimated daily intake of metals (EDIM), hazard quotients (HQs), and hazard index (HI). The rates of metal transfer to vegetables have been determined. Except for Pb and Cd, all of the elements' EDMI values were found to be lower than their RfD values. The corresponding HRI values of metals in the various vegetables were found to be below 1, implying that vegetable consumption in the studied region poses no carcinogenic risk. Constant determination of heavy metals in all fruits and vegetables is essential for the assessment of health risks associated with dietary metal exposure. The study has provided valuable information to the general public about the use of wastewater for irrigation of vegetables.

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.

Au Nanoparticles Decorated Graphene-Based Hybrid Nanocomposite for As(III) Electroanalytical Detection

Electrochemical sensors integrating hybrid nanostructured platforms are a promising alternative to conventional detection techniques for addressing highly relevant challenges of heavy metal determination in the environment. Hybrid nanocomposites based on graphene derivatives and inorganic nanoparticles (NPs) are ideal candidates as active materials for detecting heavy metals, as they merge the relevant physico-chemical properties of both the components, finally leading to a rapid and sensitive current response. In this work, a hybrid nanocomposite formed of reduced graphene oxide (RGO) sheets, surface functionalized by π-π interactions with 1-pyrene carboxylic acid (PCA), and decorated in situ by Au NPs, was synthesized by using a colloidal route. The hybrid nanocomposite was characterized by cyclic voltammetry and electrochemical impedance spectroscopy with respect to the corresponding single components, both bare and deposited as a layer-by-layer junction onto the electrode. The results demonstrated the high electrochemical activity of the hybrid nanocomposite with respect to the single components, highlighting the crucial role of the nanostructured surface morphology of the electrode and the PCA coupling agent at the NPs-RGO interphase in enhancing the nanocomposite electroactivity. Finally, the Au NP-decorated PCA-RGO sheets were tested by anodic stripping voltammetry of As(III) ion—a particularly relevant analyte among heavy metal ions—in order to assess the sensing ability of the nanocomposite material with respect to its single components. The nanocomposite has been found to present a sensitivity higher than that characterizing the bare components, with LODs complying with the directives established by the U.S. EPA and in line with those reported for state-of-the-art electrochemical sensors based on other Au-graphene nanocomposites.

Sample Preparation of Cosmetic Products for the Determination of Heavy Metals

The sample preparation of a cosmetic specimen in Cosmetic Science for the purpose of determining the analytical composition of heavy and toxic metals such as lead (Pb), mercury (Hg), cadmium (Cd), and arsenic (As) is of particular importance due to the difficulty of handling the sample. There are two main methods of sample preparation. The first method is the wet digestion of the sample with strong acids such as H2SO4, HNO3, HF, and HNO3/HCl (1:3) and the combination of a strong acid with H2O2. Liquid digestion of the sample under the influence of strong acids damages the organic material of the sample and converts the carbon into carbon dioxide. The contained metals are oxidized to the highest oxidizing step and converted to soluble salts. A problem with this method is the loss of metals during digestion because it occurs at high temperatures as well as the decrease in the concentration of the residual acid. The second method of preparation is the wet liquid digestion of the sample with strong acids in a microwave oven in a closed vessel. The acids that are used are mainly HNO3 or mixtures of acids such as HNO3–HCl and HNO3–H2SO4. When the sample in the acid’s solvent is exposed to microwave energy, it can reach temperatures substantially above the boiling temperature of the acid solution. The result is the decomposition of the organic material, the oxidation of the metals, and their conversion to soluble nitrates. The advantages of using microwaves are the ability to control the temperature, pressure, and loss of metals and, thus, avoid erroneous measurement results. Simultaneously with the above, extraction methods have been, for almost a decade, very effective complementary processes that we can use to enrich a sample of a cosmetic product. Liquid–liquid dispersion micro-extraction (DLLME) and solid phase extraction (SPE) are the two main methods used in sample preparation and are usually applied after the digestion process.

X-ray fluorescence spectrometric determination of heavy metals in selected rice samples sold on the Liberian market: a case study conducted in Paynesville City, Greater Monrovia

Background: Environmental pollution with toxic heavy metals can be lead to the possible contamination of rice. Rice is a staple food widely consumed in the urban and rural parts of Liberia daily. Rice is cultivated in approximately 113 countries and a fundamental source for energy and protein. Objective: The study assesses selected heavy metals (As, Pb, Cd, Se, and Cr) concentration in selected imported rice and traditionally grown rice and bulgur wheat in Liberia. Methods: Six grade of imported rice, Bulgar wheat, and traditionally grown rice were purchased from the Duport Road and Red-Light markets in Greater Monrovia and analyze using X-ray Fluorescence Spectrometer. All data were analyzed using XLSTAT, and data was used to calculate the risk factor of each rice sample. Results: The mean concentration of heavy metal found in the rice as follow: As, 1.31ppm; Cd, 9.42ppm; Cr. 12.3ppm; Se, 5.73ppm; and Pb, 1.75ppm. The estimated daily intakes (EDIs) were calculated in combination with the rice consumption data. The mean intakes of As, Cd, Cr, Se, and Pb through rice were estimated to be 1.32, 9.42. 12.4. 5.74, and 1.75 mg/kg BW/day. Chromium has the average estimated daily intake. The combined hazard index for the heavy metals in each sample and the total cancer risk for each sample contributed most significantly to a cancer risk of rice consumption during adult life expectancy.Conclusion: The selected heavy metal concentration from the rice sample was above the FAO/WHO reference Standard but was within the range of the contaminant level except for chromium, which is above the accepted range. However, the hazard index and the total cancer risk indicate a potential non-carcinogenic and carcinogenic risk. Â

Non-equilibrium potentiometric sensors integrated with metal modified paper-based microfluidic solution sampling substrates for determination of heavy metals in complex environmental samples

Metal modified paper-based substrates were utilized for microfluidic paper-based solution sampling coupled with Pb2+-ion selective electrodes (ISEs) with the aim of controlling the super-Nernstian response which usually occurs when using unmodified paper substrates. Potentiometric responses of Pb2+-ISEs coupled with gold, platinum and palladium coated paper substrates were investigated. Potentiometric response time was found to be predominantly dependent on the thickness of metallic layer deposited at the paper substrates. Paper-based substrates coated on both sides with 38 nm gold layers were found to be the most advantageous in controlling the super-Nernstian response of ISEs at non-equilibrium conditions. Durability studies indicated that the lifetime of Pb2+-ISEs could be doubled when used with paper-based substrates in complex environmental samples with high solid-to-liquid content. Determination of lead in real samples using metal modified paper substrates coupled with Pb2+-ISEs was validated by inductively coupled plasma optical emission spectrometry (ICP-OES). Detailed life cycle assessments were performed for model screen printed potentiometric sensors with and without metal modified paper-based solution sampling substrates. The results confirmed that the use of modified paper substrates demonstrated lower environmental impact per potentiometric measurement of Pb2+-ISE in prepared simulated environmental sample as compared to sensors without the use of paper substrates.

Determination of Heavy Metals and Anti-nutrient Residues in Selected Organs of Bovines Commonly Slaughtered in Federal Polytechnic Mubi, Adamawa State, Nigeria

This study was conducted to determine the concentrations of heavy metals (Lead, Chromium, Copper, Cadmium and Zinc) and anti-nutrients residues (phytate and oxalate) in cattle (bovines) organs slaughtered at Federal Polytechnic Mubi, Nigeria slaughterhouse. Different organs (kidney, liver, lungs, heart and spleen) were collected randomly from five different bovines as samples from slaughterhouse and were brought to the laboratory for analysis. All of the heavy metals analyzed were detected with Lead presenting 293.07 ± 163.53 mg/kg in lung, 2.97 ± 0.39 mg/kg Zinc in heart, 0.632 + 0,3724 mg/kg Cadmium, 1.53 + 1.48 2.972 2.97 ± 0.39 mg/kg Copper, 4.0E-4 ± 2.0E-4 mg/kg Chromium in liver, while highest concentration 0.63 ± 0.37 mg/kg of Cadmium and 1.53 ± 1.48 mg/kg Copper was found in spleen. The concentrations of Lead, Zinc, Copper, Cadmium and Chromium detected exceeds the recommended maximum acceptable levels proposed by the World Health Organization (WHO) which are Cadmium 0.5 mg/kg, Lead 0.30 mg/kg, Zinc 0.2 mg/kg, Chromium 1.00 mg/kg, Copper 0.1- 0.50 mg/kg. The results from this study indicate that heavy metal toxicity could result from the consumption of organs of bovines (cows) feed within contaminated areas of Federal Polytechnic Mubi, Adamawa State, Nigeria.
 Keywords: Anti-nutrient, Bovines, Heavy metals, Organs, Slaughter

Cadmium content in aquatic organisms of the Caspian Sea

Aim . Reveal the distribution of cadmium in the components of the ecosystem of the Caspian Sea. Materials and Methods . The sampling was carried out according to generally accepted methods, the determination of heavy metals was carried out by the method of atomic absorption spectroscopy using an atomic absorption spectrometer with electrothermal atomization MGA‐915 MD. Results . As a result of the studies carried out, it was found that the bottom sediments of the Middle Caspian were distinguished by a greater accumulation of cadmium than the North Caspian. Invertebrates of the Caspian Sea accumulate cadmium from water and soil, with the exception of shrimp, for which water is the only source of metal. Among the taxonomic groups of organisms studied, molluscs of the genus Didacna are cadmium accumulators. In the body of the Russian and Persian sturgeons, cadmium is mainly accumulated in the kidneys. Conclusion . Coefficients of cadmium accumulation in the organs and tissues of Russian and Persian sturgeons, black‐backed herring and Dolginsky herring relative to their food objects indicate that cadmium is able to accumulate in food chains.

Simultaneous electrochemical determination of heavy metals by an electrode modified CPE-NP-Al2O3

In the present study, A novel electrochemical sensor based on CPE-NP-M for determination of heavy metals was proposed. The electrode constructed in this work was studied in 0.3 M NaCl solution.The performance of the NP-Al2O3 for determination of Pb (II) and Hg (II) was studied using cyclic voltammetry (CV), square wave voltammetry and electrochemical impedance spectroscopy in 0.3 mol/L NaCl.Under optimized experimental parameter, the developed NP-Al2O3/CPE sensor has a lowest detection limit 0.756 and 0.5 nM for Pb (II) and Hg (II) respectively. The proposed working electrode was applied with successfully for the determination of Pb (II) and Hg (II) in tap water, and then we obtained good results.

Determination of Heavy Metals in Soil and Some Selected Vegetables Irrigated with Waste Water Along Asikolaye Stream Kaduna, Nigeria

Determination of Heavy Metals in Soil and Some Selected Vegetables Irrigated with Waste Water Along Asikolaye Stream Kaduna, Nigeria

Determination of heavy metals in water using an FTO electrode modified with CeO2/rGO nanoribbons prepared by an electrochemical method.

The rGO/CeO2/FTO nanocomposite modified electrode was prepared by an electrochemical method. A simple and highly sensitive electrochemical sensing platform for electrochemical rGO and modified CeO2 nanoribbons directly on FTO electrodes was developed. Simultaneous determination of Pb2+ and Cd2+ used the differential pulse anodic stripping voltammetry (DPASV) method. The method was simple to operate, and CeO2 nanobelts could be obtained simultaneously by electrodeposition and reduction of GO without further processing. This is an environmentally friendly electrochemical method to obtain modified electrodes under mild conditions. The experimental results showed that the linear calibration curves of Pb2+ and Cd2+ are 1–300 and 0.2–500 μg L−1, respectively. At the same time, no interference from other coexisting metal ions was found during the detection process, which proved that the modified electrode had good stability and repeatability.

Determination of proximate composition, selected essential and heavy metals in sesame seeds (Sesamum indicum L.) from the Ethiopian markets and assessment of the associated health risks

In this study, the proximate composition, levels of essential and heavy metals; and health risk assessment were evaluated in sesame seed (Sesamum indicum L.) samples purchased randomly from local markets of three study sites in Ethiopia. A 0.15 g of dried and homogenized samples were digested using 6 mL of HNO3 (69–72%) and 3 mL of HClO4 (70%) at 120 °C for 3 h. The levels of proximate composition and essential metals in the sesame samples were determined by the Association of Official Agricultural Chemists (AOAC) and Flame Atomic Absorption Spectrometer (FAAS), respectively. The moisture content, crude fiber, ash content, fat, crude proteins and carbohydrate of sesame samples ranged between 3.15% and 5.52%, 4.21–4.40%, 3.10–4.75%, 55.75–56.9%, 22.65–23.39% and 8.34–8.80%, respectively. The accuracy of the procedure was validated by percent recovery of samples for all metals varied from 85.60% to 102.00%. The mean levels of the metals (mg/kg) were found in the range of 37.20–70.10 (Na), 315.1–338.00 (K), 209.00–216.50 (Mg), 328.00–341.30 (Ca), 12.60–12.90 (Fe), 4.90–5.00 (Cu) and 8.30–8.70 (Zn) mg/kg. The THQ values of heavy metals were found < 1, indicating that the consumption of sesame may not cause health risks to local consumers. The values of HI ranged from 1.5 × 10−3 to 1.8 × 10−3 in the study areas and may not have a possible adverse health effect on the adult population from the consumption of sesame seeds.