Flame Atomic Absorption Spectrometry Research Articles

Independent components–discriminant analysis for discrimination of Brazilian Canephora coffees based on their inorganic fraction: A preliminary chemometric study

Essential element composition of new Brazilian Canephora coffees of specific origins, including both Robusta and Conilon varieties is reported for the first time. A sample set comprising 100 Canephora samples of different geographical origins (Conilon from Espírito Santo, Amazonian Robusta from indigenous and non-indigenous producers from Rondônia, and Conilon from Bahia) and Arabica coffee (25 samples) was analyzed in terms of their essential mineral content by flame atomic absorption spectrometry using diluted nitric acid to characterize their content in Fe, Ca, Zn, Mg, Mn, Cu, and K. A recent chemometric tool, independent components-discriminant analysis (IC-DA), was applied for the first time to analyze mineral composition data. IC-DA discriminated the samples according to the predetermined classes (geographical origins of Canephora and species – Arabica vs. Canephora), identifying the minerals responsible for the discriminations. IC-DA sensitivity and specificity were higher when compared to the partial least square-discriminant analysis (PLS-DA). The method is shown to be suitable to achieve supervised discrimination of samples based on their essential elemental composition, even when principal component analysis had failed. It can thus be used as a tool for origin and species discrimination based on the inorganic fraction of coffee.

Physicochemical and Microbial Quality of Water from the Ugandan Stretch of the Kagera Transboundary River

Increasing global pollution of water resources undermines the efforts invested in the realisation of Sustainable Development Goals. In developing countries, for example, water pollution is exacerbated by poor regulatory structures and improper waste disposal. This study, for the first time, investigated the physicochemical and microbial parameters of surface water from the Ugandan stretch of the Kagera transboundary river. Surface water (n = 135) from downstream, midstream and upstream of the river was sampled between February 2021 and June 2021, and analysed following standard methods for the examination of water and wastewater. Further, the samples were analysed using flame atomic absorption spectroscopy for the presence of heavy metals: nickel, lead, chromium, cadmium and copper. The obtained results showed that turbidity (24.77 ± 5.5–43.99 ± 6.87 mg/L), colour (118 ± 8.90–145.2 ± 30.58 Pt-co units), Escherichia coli (4.96 ± 7.01 CFU/100 mL), lead (23.0 ± 11.0–43.0 ± 12.0 µg/L) and cadmium (3.3 ± 1.0–10.1 ± 10.0 µg/L) were at levels that surpassed their permissible limits as per World Health Organization guidelines for potable water. These results are lower than previously reported for the Rwandese stretch of this river, but still present potential health risks to the population whose livelihoods depend on the river. Measures should therefore be instituted by the East African Community member states to mitigate riverine pollution and ensure sustainable use of the Kagera transboundary river.

Exposure Assessment of Essential and Potentially Toxic Metals in Wheat-Based Sweets for Human Consumption: Multivariate Analysis and Risk Evaluation Studies.

In recent years, there has been a growing concern about the negative impact of unforeseen contaminants such as metals in commonly consumed food items, which pose a threat to human well-being. Therefore, it is of utmost importance to evaluate the levels of these contaminants to guarantee the safe consumption of these food items. The goal of the current research is to determine the levels of essential (EMs: Mg, Ca, Mn, Fe, Co, Cu, and Zn) and potentially toxic metals (PTMs: Al, Cr, Ni, As, Cd, and Pb) in various brands of wheat-based sweets. One hundred samples were collected and analysed via flame atomic absorption spectrometry (FAAS) and inductively coupled plasma-optical emission spectrometry (ICP-OES). Also, the current study was to investigate the distribution, correlation, and multivariate analysis of 13 metals (Mg, Ca, Mn, Fe, Co, Cu, Zn, Al, Cr, Ni, As, Cd, and Pb). Hierarchical cluster analysis (HCA) and principal component analysis (PCA) were used to interpret the metals' association. The concentration (mg/kg) ranges of EMs were, in order, Mg (12.70-65.67), Ca (24.02-209.12), Mn (1.32-9.61), Fe (4.55-111.23), Co (0.32-8.94), Cu (2.12-8.61), and Zn (2.60-19.36), while the concentration (mg/kg) ranges of PTMs were, in order, Al (0.32-0.87), Cr (0.17-5.74), Ni (0.36-1.54), Cd (0.16-0.56), and Pb (0.14-0.92), and As was not detected in any sample under investigation. The HCA data revealed that Co, Al, and Ni form clusters with other metals. Sweets are prepared at high temperatures, and the elevated temperatures can increase the likelihood of Ni and Al leaching from stainless steel. Tolerable dietary intake (TDI) values for Ni were higher than the values established by the European Food Safety Authority (EFSA). The CR value found for the Ni and Cr was at the threshold level of cancer risk, if an amount of 25 g were to be used over a lifetime. In a nutshell, this study highlights the monitoring of EM and PTM levels in wheat-based sweets, and from a food safety perspective, the study is important for consumers of wheat-based sweets.

Preparation and characterization of new Mixed ligand complexes For some transition metal ions (bivalent) with Schiff- Mannich and Schiff base ligands

In this research, new mixed ligand complexes were prepared for complexes of some transitional element ions from the first transition series, which are: cobalt (II), nickel (II), and copper (II). The research included two paths:
 First: The first path included the preparation of three polycyclic ligands derived from Isatin (L1, L2, and L3), all of these ligands were identified by measuring the melting point and infrared and ultraviolet-visible spectroscopy.
 Second: The second path included the preparation of Mixed ligand complexes (L1and L2) with cobalt (II), nickel (II), and copper (II) ions. And Mixed ligand complexes (L1and L3) with ions of cobalt (II) and nickel (II). All the complexes of the new Mixed ligand were identified by the available analytical and spectroscopic methods. Based on the analytical data, the metal to ligands ratio was (1:1:1) and all complexes were characterized by various analytical techniques including (FT-IR and UV-Vis spectroscopy), CHN elemental analysis and determination using flame atomic absorption spectroscopy The percent magnetic susceptibility and molar conductivity of metal ions in the prepared complexes and these metal complexes dissolved in DMSO at a laboratory temperature of 1 × 10-3 M were also studied. by means of infrared (IR) spectra, and when compared to the spectrum of the free ligands, it was observed that some bands were displaced and others disappeared, or a change in shape and intensity occurred, which indicates a coordination occur between the metal ions and the prepared ligands. As well as the ultraviolet-visible spectrum. And detecting the presence of chloride ion inside or outside the coordination sphere. Depending on these obtained results, we were able to conclude that ligands of L1 and L2 behaves like a bi-chelate ligands, which led to the formation of mixed ligand complexes (L1, L2) with the proposed geometry of the proposed hexahedral symmetry in the presence of two chloride ions inside the coordination sphere. . Whereas, the L3 ligand behaved like a tetragonal ligand, which led to the formation of mixed ligand complexes (L2, L3) with the proposed geometry of the proposed hexahedral symmetry

Assessing Heavy Metal Contamination in Traditional Herbal Medicine (Jamu) by Atomic Absorption Spectrophotometry

Heavy metal contamination of traditional herbal medicine (jamu) is a threat to humans, especially at levels above known threshold concentrations. Traditional herbal medicine found in Banda Aceh City – Indonesia, polluted by heavy metals cadmium (Cd), lead (Pb), and mercury (Hg) was performed. Heavy metal analysis used Flame - Atomic Absorption Spectrometry (FAAS) and Chemical Vapor Generation - Atomic Absorption Spectrometry (CVG - AAS) methods. The validation of the method was performed to obtain more accurate heavy metal analysis results for the samples. Heavy metal contamination, especially Pb metal, with concentrations of 4.32 ± 0.14 mg/Kg to 29.25 ± 0.24 mg/Kg. The Cd metal contamination was only found in herbal medicine sample E with a concentration of 0.80 ± 0.02 mg/Kg, above the threshold. The Hg metal contamination was also found with concentrations of 0.20 ± 0.01 to 2.14 ± 0.06 mg/Kg, and some were not detected. The government should be very concerned about stopping the distribution of herbal medicine that can be harmful to health and should inspect drug stores that still sell herbs that do not have established standards.

Influence of Isoflavones and Probiotics on Magnesium Status in Healthy Female Rats.

Isoflavones and probiotics are promising nutrients for bone health, and magnesium (Mg) is essential for bone metabolism. This study aimed to determine the effects of daidzein, genistein and Lactobacillus acidophilus on the Mg status of healthy female rats. Forty-eight rats were randomly assigned to six groups, with the control group receiving a standard diet (AIN 93M). The remaining groups were fed the same diet with added ingredients such as tempeh flour; soy flour; pure daidzein and genistein; L. acidophilus or a combination of daidzein, genistein, and L. acidophilus. Tissue samples were collected after the eight-week intervention, and Mg concentrations were analysed using flame atomic absorption spectrometry. Myeloid and erythroid cells were determined using the haematoxylin and eosin bone staining method. Statistical analyses were conducted using one-way ANOVA with Tukey's post hoc test and Pearson's correlation coefficient. The threshold for significance was p < 0.05. Compared with the control group, adding tempeh to the diet of rats resulted in significant changes in Mg concentrations in various tissues, with a decrease in the kidneys and an increase in the fur. Although not statistically significant compared to the control group, the tempeh group showed increased Mg concentrations in the femur and spleen. The myeloid-to-erythroid cell ratio did not differ significantly among groups, but all intervention groups showed higher ratios than the control group. A strong negative correlation was observed between Mg concentrations in the kidneys and fur. Conversely, a positive correlation was identified between Mg concentrations in the pancreas and fur. Daily consumption of tempeh may improve Mg status in the organism. Intake of pure daidzein, genistein, or probiotic seems to have no effect on Mg concentrations in healthy rats.

Analytical application of flower-shaped nickel nanomaterial for the preconcentration of manganese in domestic wastewater samples.

In this study, detection sensitivity of the conventional flame atomic absorption spectrophotometer (FAAS) for the determination of manganese (Mn2+) was enhanced by employing a preconcentration method from wastewater samples. Flower-shaped Ni(OH)2 nanomaterials were synthesized and used as sorbent material in preconcentration procedure. With the aim of attaining optimum experimental conditions, effective parameters of extraction method were optimized and these included pH of buffer solution, desorption solvent concentration and volume, mixing type and period, nanoflower amount, and sample volume. The detection limit of the optimized method was determined to be 2.2 μg L-1, and this correlated to about 41-fold enhancement in detection power relative to direct FAAS measurement. Domestic wastewater was used to test the feasibility of the proposed method to real samples by performing spike recovery experiments. The wastewater sample was spiked at four different concentrations of manganese, and the percent recoveries determined were in the range of 95-120%.

Simultaneous complexation and extraction of manganese in melissa tea sample by deep eutectic solvent based liquid phase microextraction

Manganese at trace levels cannot be detected by flame atomic absorption spectrophotometer (FAAS) without a preconcentration method. In the presented study, an accurate and sensitive analytical method for the determination of manganese at trace levels in melissa tea samples was established. Deep eutectic solvent based liquid phase microextraction (DES-LPME) was used to preconcentrate the analyte from aqueous medium. Several important parameters were individually optimized to achieve high signal to noise ratio for the analyte in FAAS system. Under the optimum experimental conditions, limit of detection (LOD), limit of quantitation (LOQ) and linear range (LR) for the developed DES-LPME-FAAS system were found as 1.7 µg/kg, 5.8 µg/kg and 6.5–202.8 µg/kg, respectively. Enhancement in detection power was calculated as 112.2 folds by dividing manganese LOD value in FAAS system to value obtained by DES-LPME-FAAS system. Three different melissa tea samples were analyzed by the proposed method to find their manganese content. Percent recovery results for the tea samples ranged between 80.4% and 122.6% with low standard deviation values.

Variations in elemental composition of rice (Oryza sativa L.) with different cultivation areas of Ethiopia.

Variations in the elemental composition of rice (Oryza sativa L.) grains, and the link with the growing soil, were investigated across the major production areas of Ethiopia (Fogera, Metema and Pawe). The elements (Ca, Mg, Fe, Zn, Mn, Cu, Ni, Cr, Cd and Pb) were determined by using flame atomic absorption spectroscopy (FAAS), after digesting samples through an optimized procedure with respect to volumes of reagents (HNO3, HClO4 and H2O2), temperature and time. The accuracy of the FAAS method was in the range of 87‒113%. The most abundant element in rice was Mg (414‒561 mg kg-1) followed by Fe (49.4‒168 mg kg-1), while in soil was Fe (11674‒12917 mg kg-1) followed by Mg (619‒709 mg kg-1). Chromium, Cd and Pb were all below the limit of quantitation of the method. The concentrations of the elements, except Zn in rice and Fe in soil, varied significantly (p < 0.05) with the growing region. Notably, rice from Fogera contained more than double Fe, while from Pawe less than half Cu than from the other region. Soils from the rice fields of Pawe, generally, had lower levels of the elements than from the other regions. The order of the abundances of the elements in soil was reflected in the rice grains, except for the reversal between Fe and Mg. However, elemental concentrations were higher in soil than in rice, indicating the absence of bioaccumulation by the rice grains. Furthermore, only copper exhibited a strong positive correlation (r = 0.991) between the rice grain and soil.

Trace Metals in PM10 and Associated Health Risk in Two Urban Sites Located in Campeche

This study reports the trace metal concentrations in PM10 collected in two urban sites of Campeche, Mexico (the INAH site, located in the downtown, and the TNL site, located in the Tecnologico Nacional de Mexico campus Lerma). Trace metals (Cd, Co, Cu, Fe, Mn, and Zn) were determined by flame atomic absorption spectroscopy, with Fe and Mn being the most dominant species. Cd and Co showed high values of enrichment factors, indicating that they were highly enriched by anthropogenic sources. A health risk assessment was carried out according to the IRIS-EPA methodology considering both carcinogenic and non-carcinogenic effects and different age and gender population groups. The TNL site showed cancer risk coefficients that exceed the maximum limits established by the EPA and the WHO (1 × 10−6 and 1 × 10−5, respectively), being higher for Cd and Co. The non-carcinogenic risk exceeded the limits recommended by the EPA, being higher in the INAH site for cobalt (HQ = 28.92). There is a latent risk that the exposed population may develop cardiovascular and respiratory diseases due to inhalation of the metals measured in PM10. It is necessary to carry out more continuous monitoring campaigns of trace metals linked to PM10 in this area to enable a better understanding of the effects of these contaminants on the health of the exposed population. The results of the present work constitute the first efforts to evaluate the trace metals concentrations in PM10 in urban areas of the city of Campeche, Campeche and can be used to develop programs focused on improving air quality.

In vitro techniques for evaluating smear layer removal by root canal irrigants: a literature review

Introduction: The purpose of this review is to address the most commonly used techniques for evaluating smear layer removal ability or chelating capacity of root canal irrigants, including Energy Dispersive X-Ray Spectroscopy (EDS or EDX), Atomic Absorption Flame Spectrometry (AASF), wavelength dispersive X-ray fluorescence spectrometry (WDXRF), inductive coupled plasma emission spectroscopy (ICP-AES), Scanning Electron Microscopy (SEM), and Fourier Transform Infrared Spectroscopy (FTIR). Methods: An electronic literature search was conducted in the Pub Med / MEDLINE database of indexed journals from 1992 to 2020. The search terms included chelating, chelation, calcium chelation, smear layer, smear layer removal, and demineralizing effect. Results: All the techniques were classified in terms of their results, both quantitatively and qualitatively. Even though smear layer removal and chelating capacity are not the same parameters, most of the studies included both techniques to correlate their results. SEM is the most commonly used technique for evaluating smear layer removal using various root canal irrigants. Ethylenediaminetetraacetic acid (EDTA) (17%) was the most widely studied root canal irrigant. Conclusion: Different techniques can be used to evaluate smear layer removal and chelating capacity of root canal irrigants. All of these methods have their corresponding advantages and disadvantages. This study aimed to provide researchers with a background for the selection of technique(s) to study the irrigant´s capacity for calcium chelation, which is applicable to smear layer removal.

Evaluation of Heavy Metal Presence in Agricultural Samples of Lactuca sativa and Trifolium alexandrinum Using Picosecond Laser-Induced Breakdown Spectroscopy and Flame Atomic Absorption Spectroscopy in Banha and Giza Governorates, Egypt

This pioneering study utilizes Flame Atomic Absorption Spectroscopy (FAAS) and Picosecond Laser-Induced Breakdown Spectroscopy (Ps-LIBS) to quantify heavy metal contents in samples of Lactuca sativa L. and Trifolium alexandrinum L. collected from Banha and Giza, Egypt for the first time. In order to enhance the performance of Ps-LIBS, laser parameters were carefully optimized. Expressly, laser energy was set to 100 ± 5% J/cm², pulse duration was calibrated to 170 picoseconds, and 1064 nm Nd: YAG pulses were employed. This optimization facilitated the creation of linear LIBS calibration curves, a crucial element in ensuring precise elemental quantification and bolstering the overall analytical reliability. The assessment of pollution indices revealed concerningly high levels of copper, nickel, and cadmium consistently across all study sites. Lactuca sativa L. and Trifolium alexandrinum L. also demonstrated multiple metals’ bioaccumulation factors (&gt;1), further underscoring the potential health risks associated with copper, nickel, and cadmium contents. Given these findings, it is imperative to recommend constructing a dedicated wastewater treatment facility to address Al Mansouria village’s environmental challenges in the Giza governorate.

One-pot/one-step synthesis of Bi2O3/ZnO/Pd nanocomposite for preconcentration and determination of some heavy metal ions in different samples

ABSTRACT In this contribution, a new green eco-friendly synthesised nanocomposite (Bi2O3/ZnO/Pd) was fabricated by one-pot/one-step method, using ultrasonic waves. The nanocomposite was used for pre-concentration of some heavy metals, i.e. cadmium (II), lead (II), and copper (II), exploiting ultrasound-assisted dispersive micro solid phase extraction (UA-D-μ-SPE) method, before their determination by flame atomic absorption spectroscopy (FAAS). The adsorbent synthesis was confirmed by XRD, SEM, BET, TEM, EDS, and TGA analyses. The central composite design (CCD) method was employed to optimise various parameters affecting the extraction of heavy metals. The effective parameters in the adsorption process, viz. the amount of adsorbent (16 mg), pH of the sample solution (6.2), and adsorption time (4 min), were optimised. The type and the concentration of eluting agent (HCl solution) was investigated as one parameter at a time. Impressive parameters in the desorption stage such as the volume and concentration of eluting solution (400 μL of 0.8 mol L−1 HCl) and desorption time (2.5 min) were optimised. In the best extraction conditions for cadmium (II), lead (II), and copper (II), the limits of detection (LODs) were 0.75, 2.1, and 0.90 ng mL−1; the limits of quantification (LOQs) were 2.5, 7.0, and 3.0 ng mL−1; the linear dynamic ranges (LDRs) were 2.5–100, 7.0–600, and 3.0–250 ng mL−1; preconcentration factors (PF) were 24.10, 25.20, and 25.39; and the relative standard deviations (RSDs%) were 3.7, 4.1, and 3.8 (n = 5), respectively. Additionally, the adsorbent had the ability to extract metals up to 8 times without a significant decrease in the extraction percentages. The adsorbent was successfully used in the determination of cadmium (II), lead (II), and copper (II) ions in different food, biological, cosmetic, and water samples.

Determination of Thallium in Tea with Preconcentration by Microwave-Assisted Synthesized Molybdenum Disulfide Nanoparticles and Flame Atomic Absorption Spectrometry (FAAS) Analysis

A simple, quick and environmentally friendly microwave-assisted synthesis method was developed to produce MoS2 nanoparticles (MoS2NP) for the preconcentration of thallium. The characteristics of the synthesized MoS2NP were validated by x-ray diffraction (XRD) and scanning electron microscopy (SEM). The determination of thallium was achieved with MoS2NP based preconcentration and a flame atomic absorption spectrophotometer (MoS2NP-PM-FAAS). A detection limit of 14.6 µg/kg was achieved for thallium using the optimum conditions by the MoS2-PM-FAAS method. The developed method provided an improvement in the detection power of the FAAS system by approximately 20-fold. The applicability of the method was validated with tea samples through spike recovery experiments.

Distribution, Accumulation, and Risk Assessment of Pb and Cd in the Tea Plant Leaves, Black Tea, and Soil from Different Tea Plantations in Lahijan, Iran

Since heavy metals (HM) exist in the soil due to industrial activity and the usage of pesticides and fertilizers, monitoring the content of these pollutants is very significant. The current research aimed to determine the concentrations of cadmium (Cd) and lead (Pb) in the tea plant leaves, black tea, and soil and look for their correlations. Twenty-seven (27) samples were divided into three groups of tea plant leaves, black tea, and soil from the same tea plantations originating from Lahijan, Iran. The concentrations of Pb and Cd in samples were determined using a flame atomic absorption spectrophotometer. After that, some analyses were conducted to find the correlation between the content of Pb and Cd in tea plant leaves, black tea, and soil, and their health risks were evaluated. In leaves, black tea, and soil, the mean contents for Cd were 0.001, 0.044, and 0.044 ppm, whereas those for Pb were 0.501, 0.939, and 2.093 ppm, respectively. The results showed that Cd and Pb concentration means in tea plant leaves, black tea, and soil samples were lower than the guidelines recommended by EU, WHO, and national Iranian standards (P &lt; 0.05). The values of the non-carcinogenic hazard quotients (HQ) and the hazard index (HI) were below 1, indicating that these two HMs will not adversely affect consumers' health through the oral pathway of drinking tea. However, more attention should be paid to monitoring the content of HMs in soil. This research recommends that soil Pb contamination should be managed to ensure safe tea production in the study area. An effective management strategy appears necessary to ensure the quality and safety of tea plantations, as well as to reduce the risk of the accumulation of HMs in tea.

Synthesis, characterization and application of cross-linked functional terpolymer through epoxy group as sorbent for extraction of cadmium from waters and foods: Multivariate optimization

The purpose of this study was to develop a selective sorbent for cadmium ions (Cd(II)) enrichment in orbital shaker assisted solid phase microextraction (OS-SPME) from different aqueous and food samples. A maleic anhydride-styrene-glycidyl methacrylate (MA-St-GMA) terpolymer was synthesized and characterized in detail. Experimental variables of sample preparation step were optimized using a central composite design (CCD). The final determination step was performed using flame atomic absorption spectroscopy (FAAS). The MA-St-GMA sorbent exhibited a high adsorption capacity (195.9 mg g−1) for the Cd(II) ion. The developed method under optimal conditions provides satisfactory performance and a significant improvement compared to other protocols available in the literature. The linear range and detection limit of the method is 0.1–130 ng mL−1 and 0.03 ng mL−1, respectively. The robustness, intraday/interday precision, selectivity, and accuracy of the method were investigated. To further validate the method, a dedicated series of analysis was performed using certified reference materials (CRMs). This part of the study confirmed the applicability of the method for routine analysis. The OS-SPME-FAAS method was validated using water and food samples. Relative standard deviations and recovery for real-world samples were in ranges 1.7–2.2 % and 95.5–98.5 %, respectively. As a result, the MA-St-GMA sorbent showed that it could quantitatively extract Cd(II) ions from aqueous solution.

Determination of zinc content in insulin products by inductively coupled plasma mass spectrometry

Scientific relevance. Zinc content is a quality attribute of insulin products. The State Pharmacopoeia of the Russian Federation requires that it should be determined by flame atomic absorption spectrometry (FAAS). However, many pharmaceutical manufacturers currently prefer inductively coupled plasma mass spectrometry (ICP-MS), which is considered the most promising method for pharmaceutical and biomedical elemental analysis.Aim. The study aimed to develop and validate an ICP-MS-based analytical procedure for zinc content determination in insulin products.Materials and methods. The study focused on human insulin, insulin lispro, insulin aspart, and insulin glargine in the form of active substances, suspensions for subcutaneous injection, and solutions for injection from different manufacturers. Zinc content was determined on an Agilent 7900 ICP-MS; the analysis included 66Zn signal intensity registration.Results. The study compared the results of zinc content determination in test samples with either hydrochloric or nitric acid used as the solvent for sample preparation. The authors selected the experimental conditions to achieve relative standard deviations (RSDs) of not more than 2.5% for the measurements. The ICP-MSbased analytical procedure was validated for its specificity, linearity, accuracy, and precision in the range of 0.4–1.6 mg/L. The authors compared the measurements of zinc content made using FAAS and ICP-MS.Conclusions. The ICP-MS-based analytical procedure for zinc content determination in insulin products meets the validation criteria. This analytical procedure, as developed and validated, may be used in the quality control of medicinal products in the Russian healthcare system and at the batch release stage of pharmaceutical manufacturing.

Determination of Lead in Herbal Medicine by a Lab-on-a-Tip (LOT) Optical Fiber Sensor

A lab-on-a-tip (LOT) has been constructed as a sensing platform for the detection of lead using a disposable pipette tip. The LOT has been constructed with optical fiber spectroscopy where the inside wall of a pipette tip is modified with a polymeric inclusion membrane (PIM) immobilized with dithizone as a chemical sensor for Pb(II) in herbal samples. Under optimal conditions, the LOT determined Pb(II) across a linear concentration range from 1.9 to 20 mg/L with a detection limit of 0.621 mg/L. The analysis of samples shows good agreement with the flame atomic absorption spectroscopy (FAAS).

Lead, Cadmium, and Arsenic in Raw Cow's Milk in a Central Andean Area and Risks for the Peruvian Populations.

Milk and its derivatives are basic foods in Peru, especially for children. The Junín region, in the central Andes, is one of the leading dairy basins. However, the safety of milk is affected by mining-metallurgical activities, wastewater dumping, organic residues, and inappropriate use of organophosphate fertilizers in agriculture whose contaminants reach the food chain, putting human health at risk. The purpose of this study was to evaluate the bioaccumulation of lead (Pb), cadmium (Cd), and arsenic (As) in milk produced on a representative farm in central Peru, which uses phosphorous agrochemicals and is adjacent to a small mineral concentrator and a municipal solid waste dump, and to evaluate the potential risk for the Peruvian population of 2-85 years considering three levels of daily intake by age, which constitutes the innovative contribution of the study. These three elements were quantified by flame atomic absorption spectrometry following standardized procedures. The mean contents of Pb (0.062 mg/kg), Cd (0.014 mg/kg), and As (0.030 mg/kg) in milk exceeded the maximum limits allowed by international standards. At all ages, the target quotient hazard followed a descending order of As > Pb > Cd, being > 1 in the case of As. The hazard index was >1 for children under 7, 9, and 11 years of age in the scenarios of low, medium, and high milk intake. The information is valid for formulating policies to prevent adverse health effects and develop standards and awareness programs, monitoring, and control of heavy metals in milk in Peru.

Mapping copper concentrations in tropical open cast mining fronts from X-ray fluorescence and FAAS techniques: A comparative study

Determining copper (Cu) contents and their spatial distribution in tropical open cast mining fronts is crucial for short-term exploitation planning. However, this evaluation in a fast and accurate way can be directly impaired by methods applied. The aim of this work was to assess the analytical performance of portable X-Ray fluorescence (pXRF) for Cu analysis in the mining fronts at the Cu Sossego Mine, in the Carajás Mineral Province, State of Pará, Brazil. For this, 143 drilling samples were collected in mining fronts at the Sequeirinho pit, an area chosen as representative of the heterogeneity of the Cu levels in the deposit of Sossego Mine. The samples were analyzed with three different techniques to determine the Cu levels as follows: pXRF; wavelength-dispersive X-Ray fluorescence (WDXRF); and flame atomic absorption spectrometry (FAAS) after acid digestion with aqua regia (reference method). Results of the three analytical methods were used to generate block models through Leapfroag Geo 6.0 software. Portable XRF data presented a strong positive correlation (>0.70) with the results obtained by the FAAS. In addition, pXRF performed better than WDXRF, with less dispersed values compared to FAAS. Similar distribution maps were generated using the three methods of analysis. After correction, the average Cu content from the pXRF-generated block model was only 0.15% lower than that derived from FAAS data. Therefore, pXRF is a fast, portable, non-destructive, low-cost, accurate and recommendable method for mining front sample analysis and to assist the quality control and geoscience teams in decision-making for feeding the mineral processing plant.