Atomic Absorption Spectrometry Technique Research Articles

New Design Valve in Flow Injection System for the Determination of Pb(II) in Biological and Environmental Samples

A strategy to design an injection valve for a streamlined flow injection technique is described as speed and low-cost materials available in the environment for the determination of Pb(II) ion using the organic reagent 4-((4-methoxyphenyl)diazenyl)benzene-1,3-diol at a wavelength of 498 nm. The scope of the study is to find the optimal conditions, including the flow rate of the carrier, the dispersion coefficient, the length of the reaction coil, and the calibration drawing. The results showed that the optimum length of the reaction coil is 20 cm, and the optimum flow rate is 9.1 mL/min, which is equivalent to the pumping rate of 70 F/min. The range of linearity of the study was revealed by a calibration curve of 0.5–27 mg/L, slope = 1.507, correlation coefficient = 0.9995, the limit of quantitative (LOQ) = 0.088 mg/L, and limit of detection (LOD) = 0.026 mg/L. The system under study has a characteristic efficiency. The dispersion coefficient was calculated for concentrations of 10–15 mg/L Pb(II) ion. Furthermore, the accuracy of the flow injection technique in the estimation process was studied and compared with the Flame Atomic Absorption Spectroscopy (FAAS) technique.

Intoxicação crônica por chumbo em uma onça pintada (Panthera onca) alvejada com projéteis de chumbo - relato de caso

ABSTRACT Lead is a heavy metal and an important cause of acute or chronic toxicosis in humans, domestic, and wild animals. This report aims to describe a case of chronic lead poisoning in a jaguar (Panthera onca) kept under human care that was rescued from the wild environment. The animal was rescued in poor condition in 2004 and kept under human care at the Belo Horizonte Zoological Garden (Minas Gerais, Brazil) until 2020, when it presented with anorexia, vomiting and ataxia. Over the past years the animal had episodes of anemia and increased serum urea and creatinine. Radiography demonstrated 21 radiopaque projectiles on the right side of the face. At necropsy there were multiple projectiles surrounded by fibrous tissue in the subcutaneous of the right side of the face, fibrinous peritonitis, multiple gastric ulcers, and melena. The lead dosage was performed using the atomic absorption spectrometry technique using renal tissue collected at necropsy, with a result of 908 ppb (µg/kg). The findings of projectiles associated with the dosage of lead above the reference limits allow the diagnosis of chronic intoxication in this case.

Contamination, ecological and health risk assessments of potentially toxic elements in soil around a municipal solid waste disposal facility in Southwestern Nigeria

BackgroundThe increasing level of waste generated and disposed of especially in urban centers arising from population explosion and rapid industrialization is a global concern, because it may lead to the pollution of potentially toxic element (PTE) in surrounding soils and groundwater. This research is aimed at the investigation of PTE contamination in soil around a municipal solid waste open dump facility and their human health risk in Ibadan, Southwestern Nigeria. MethodsForty (40) soil samples were collected at 20 cm depth within the facility (WFC), close to the facility (CFC), and far from the facility (FFC). The soil samples were analysed for Cd, Co, Cu, Mn, Ni, Pb, and Zn using atomic absorption spectrometry technique. ResultsOn the basis of the mean concentration, PTEs decrease in the following order Zn > Mn > Pb > Cu > Co > Ni > Cd. The contamination statuses of Cd, Cu, Pb and Zn were high-very high at WFC, moderate-high at CFC, and low-moderate at FFC. The principal component (PC) analysis showed three loadings; PC1 composed of Cd, Cu, Pb, and Zn that were attributed to anthropogenic input from the materials dumped within facility while PC2 (Co and Ni) and PC3 (Mn) were sourced from the geogenic origin from weathering of rocks and soils. Only the ecological risk potential (Er) of Cd and Pb was high at WFC, considerable at CFC and low at FFC and affect the overall ecological risk (RI) of WFC and CFC. The hazard quotient and hazard index of non-carcinogenic risk were only > 1 for Cd especially for children at WFC and therefore, may pose health risk in the vicinity of the facility. The carcinogenic risk (CR) is within permissible limit. ConclusionThe anthropogenic activities in the municipal solid waste facility have impacted the soil of the area by some PTEs and posed potential human health risk to the people living close to the site. Therefore, constant monitoring of the area by regulatory bodies is recommended to reduce the impact of the PTEs on the soil.

Study of the Adsorption Efficacy of Cr(III) on a Metal Oxide-Based Material Derived from the Quartz Sand Enrichment Process

In the present study, the efficacy of chromium removal from water media was studied. For this purpose, a metal oxide based material, derived from the enrichment process of quartz coastal sand was used as possible adsorbent of chromium (III) ions. Following additional modification of the adsorbent, the effect of operational parameters including pH, contact time and Cr(III) concentration were studied according to one-factor-at-a-time procedure. Adsorption efficacy was assessed by the measurement of the remaining chromium concentration in solution, after adsorption. Atomic absorption spectroscopy technique, with flame atomization was used for the determination of chromium concentration in solution. Obtained results revealed that selected material exhibited higher adsorption efficacy in alkaline solution (pH = 6-9). The maximum removal efficacy (>93%) was achieved after 180 minutes of contact time, with an adsorbent dosage of 5 g/L and initial chromium concentration 20 mg/L. The adsorption process for Cr(III) follow the Freundlich isotherm and gives high correlation coefficient R². Calculations performed based on the Langmuir isotherm showed that the maximum adsorption efficiency of Cr³⁺ in the natural metal-oxide material has resulted 10 mg/g or 10000 μg/g. Pseudo second order reaction kinetics has provided a realistic description for removal of Cr(III) from solution with high correlation coefficient R² of (0.999). The adsorption isotherms were better described by the Freundlich equation (R² = 0.934). Adsorption of trivalent chromium ions onto selected material followed the pseudo second order model (R² = 0.996). Hence, the residual materials derived from the enrichment processes of quartz sand can be used as alternative adsorbent for the removal of trivalent chromium ions from aqueous solutions.

Rapid and Robust Analytical Method for the Determination of Copper Content in Commercial Pesticides and Antifouling Biocides

The quality control of the agrochemicals and biocidal products in the market requires valid determination methods for the active ingredient content and is of utmost interest to ensure environmental protection, human health, and successful pest control. Copper has been used as fungicide for centuries, and today is still in the market in hundreds of products for various uses and is applied in very high application rates, both in pesticides and biocides. The aim of the present study was to develop a new fast, efficient, and inexpensive analytical method for the determination of copper content in antifouling Product Type 21 (PT-21) biocides as well as in copper containing pesticides. The samples were oxidized by microwave-assisted acid digestion method and copper content was determined by flame atomic absorption spectrometry technique. The recoveries of the method ranged from 87.9% to 97.6% for antifouling paints, and 98.6% to 99.95% for pesticides, while the percentage Relative Standard Deviation (%RSD) was lower than 6% in all cases. The validated method Limit of Quantification (LOQ) was 5 μg mL−1 that was sufficient for the present analysis needs. As a result, it is concluded that the method is easily applicable and transferable, with reasonable consumption of reagents, characterized by high reliability and sensitivity; therefore, it is suitable for monitoring the levels of copper in antifouling products as well as pesticides containing copper as active substance.

Chemical characteristics of bottom ash from biomedical waste incinerators in Ghana.

Biomedical waste (BMW) incineration is the most used alternative disposal method in developing countries, such as Ghana. The improper disposal of incinerator-generated bottom ash (BA) is a significant concern due to the hazardous nature of waste. A study was conducted at Tema Hospital (TGH) and Asuogyaman Hospital (VRAH) incinerator sites. The BA samples were sent to the Council for Scientific and Industrial Research, Institute of Industrial Research, Ghana. The BA samples were weighed with fisher analytical balance, ground, and sieved with standard grade meshes of 120, 100, and 80 to determine the BA particle size distribution. The chemical composition and heavy metals were analysed using X-ray fluorescence spectrometry (XRF) and atomic absorption spectroscopy (AAS) techniques. The results indicated the chemical composition of the analysed BA samples was CaCO3 (49.90%), CaO (27.96%) and MgCO3 (6.02%) for TGH and CaCO3 (48.30%), CaO (27.07%), and SiO2 (6.10%) for VRAH, respectively. The mean concentration (M) (kg m-3) and standard deviation (SD) for TGH in the BA were 7.082 ± 0.478 (Ti), 4.657 ± 0.127 (Zn) and 4.271 ± 1.263 (Fe), while that of VRAH consisted of 10.469 ± 1.588 (Ti), 7.896 ± 2.154 (Fe) and 4.389 ± 0.371 (Zn). Therefore, the heavy metals' mean concentration at the BA is above the WHO permissible limits of soil, i.e., 0.056kgm-3 (Ti), 0.085kgm-3 (Pb), 0.100kgm-3 (Cr) and 0.036kgm-3 (Cu). Furthermore, the heavy metal mean concentrations of TGH and VRAH present in the BA analysed samples were ranked in descending order: Ti > Zn > Fe and Ti > Fe > Zn, respectively. It is therefore recommended that BA must be properly disposed of because of the hazardous nature of heavy metals present in the analysed samples, which are able to cause environmental and public health issues.

A halophilic Chromohalobacter species from estuarine coastal waters as a detoxifier of manganese, as well as a novel bio-catalyst for synthesis of n-butyl acetate.

Anthropogenic pollution due to ferro-manganese ore transport by barges through the Mandovi estuary in Goa, India is a major environmental concern. In this study a manganese (Mn) tolerant, moderately halophilic Chromohalobacter sp. belonging to the family Halomonadaceae was isolated from the sediments of a solar saltern adjacent to this Mandovi estuary. Using techniques of Atomic absorption spectroscopy, Scanning electron microscopy-Energy dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy and Atomic Force Microscopy, the Chromohalobacter sp. was explored for its ability to tolerate and immobilize Mn in amended and unamended media with 20% natural salt concentration (w/v). In aqueous media supplemented with 0.1 mM Mn, the Chromohalobacter sp. was capable of sequestering up to 76% Mn with an average immobilization rate of 8 mg Mn /g /day. Growth rate kinetic analysis using Gompertz mathematical functions was found to model the experimental data well. The model inferred that the maximum growth rate of Chromohalobacter sp. was at 10% natural salt concentration (w/v). The Chromohalobacter sp. was further found to be multimetal tolerant showing high tolerance to Iron (Fe), Nickel (Ni) and Cobalt (Co), (each at 4 mM), and tolerated Manganese (Mn) up to 6 mM. Morphologically, the Chromohalobacter sp. was a non-spore forming, Gram negative motile rod (0.726 μ× 1.33 μ). The adaptative mechanism of Chromohalobacter sp. to elevated Mn concentrations (1 mM) resulted in the reduction of its cell size to 0.339 μ× 0.997 μ and the synthesis of an extracellular slime, immobilizing Mn from the liquid phase forming Manganese oxide, as confirmed by Scanning Electron Microscopy. The expression of Mnx genes for manganese oxidation further substantiated the finding. This bacterial synthesized manganese oxide also displayed catalytic activity (∼50% conversion) for the esterification of butan-1-ol with CH3COOH to yield n-butyl acetate. This Chromohalobacter sp. being indigenous to marine salterns, has adapted to high concentrations of heavy metals and high salinities and can withstand this extremely stressed environment, and thus holds a tremendous potential as an environmentally friendly "green bioremediator" of Mn from euryhaline environments. The study also adds to the limited knowledge about metal-microbe interactions in extreme environments. Further, since Chromohalobacter sp. exhibits commendable catalytic activity for the synthesis of n-butyl acetate, it would have several potential industrial applications.

Removal of Ni2+ and Pb2+ IONS from Aqueous Medium Using Unmodified and 4-Aminophenol Modified Red Onion Skin Extract

The extraction of Ni2+ and Pb2+ ions from aqueous medium using unmodified (ROSE) and the 4-aminophenol modified red onion skin extract (ROSEDS) has been successfully achieved. Cold solvent extraction technique using a 50:50 acetone/water ratio was used for extraction of the red onion skin at 125 µm mesh size. The metal concentrations were determined using Atomic Absorption Spectrometry technique. Optimum percentage removal of the metal ions was achieved at pH 6.26 for Ni2+ (89.40 % for ROSE and 97.60 % for ROSEDS) and pH 7.57 for Pb2+ (80.10 % for ROSE and 82.56 % for ROSEDS). Optimum adsorption capacities of ROSE and ROSEDS for Ni2+ were 6.30 mg/g and 7.10 mg/g respectively; while for Pb2+ ions, values obtained for ROSE and ROSEDS were 5.87 mg/g and 6.34 mg/g respectively. Varying adsorbents dosage at fixed metals ion concentration yielded optimum percentage removal of 89.90 % and 97.90 % for Ni2+, while 86.85 % and 90.80 % for Pb2+, using ROSE and ROSEDS, respectively. Adsorption capacities of the adsorbents varied inversely with adsorbent dosages. In general, 4-aminophenol modified red onion skin extract (ROSEDS) gave comparatively, better results for the extraction of Ni2+ and Pb2+ ions from aqueous medium; relative to the unmodified red onion skin extract (ROSE). Additionally, extraction of Ni2+ ions gave higher percentage removal values in both adsorbents when compared to extraction of Pb2+ ion under similar conditions. This result has been attributed to differences in their ionic radii. REVIEW ARTICLE | April 4, 2023

Exposure risk to heavy metals through surface and groundwater used for drinking and household activities in Ifite Ogwari, Southeastern Nigeria

Surface and groundwater are the most common sources of water in Nigeria's rural communities, which are used for a variety of purposes ranging from farming to industrial processes and other domestic household activities including drinking. Water that contains heavy metals in excess of the maximum permitted levels poses a risk to human health. This study aims to evaluate the levels of heavy metals in surface and groundwater in Ifite Ogwari, a rural community in Anambra State, Southeast Nigeria, as well as their ecological indices and human health risks assessment. The concentration levels of Ni, Cr, Cd, Pb, Zn, Fe, Mn, and Cu were determined in fifteen water samples from the major water sources in the study area, viz., streams, river, and hand-dug wells. The water samples were collected using precleaned 500 cm3 glass bottles and were analyzed using Atomic Absorption Spectroscopy (AAS) technique. The results showed that four metals (Cr, Cu, Mn, and Pb) out of the eight heavy metals were not detected in all the samples. The concentration levels of total Ni had a range of 0.029–0.11 mg/L with highest concentration occurring at Isiachala stream, Onowulugbe well, and Omambala river (0.11 mg/L). The Cd levels in the water samples had a range of 0.001–0.036 mg/L, with Isiachala and Iyiutu having the highest values (0.036 mg/L). The concentration of Fe ranged from 0.01 to 0.047 mg/L. Mn was detected at a concentration level of 0.003 mg/L in Iyiutu stream only. The Pearson correlation deduced a strong correlation (> 0.75) and a medium correlation (0.50–0.75) for sample locations and analytes, while three factors (principal component analysis) were produced, which indicates the influence of anthropogenic release rather than natural release. Ecological indices showed the impact of multi-elemental matrices on the ecology, while health risk assessments showed that there was no adverse cancer risk or non-cancer risk across respondents (adults and children). The obtained results showed that anthropogenic release has an extensive mobility influence on the natural level of metals in surface and ground water in Ifite Ogwari, and so proper treatment is advocated. This study has shown that the water sources from Ifite Ogwari pose no adverse health risk to the residents. Consequently, additional research on Ifite Ogwari water is needed to characterize “forever chemicals,” per- and polyfluoroalkyl substances (PFAS) which are ubiquitous, cancerous and have been linked to reproductive and immune system harm, and suggest routes for remediation.

Assessment of selected heavy metals in soil samples from mechanical workshop in Azare Town, Katagum Local Government, Bauchi State, Nigeria

This study evaluated the level of different selected heavy metals namely; Cadmium (Cd), Copper (Cu), Lead (Pb), Manganese (Mn) and Zinc (Zn) pollutants in soil sample, from Azare mechanical workshop (Babban Gareji), Katagum Local Government, Bauchi State, Nigeria. The soil were collected using stainless steel soil auger, from the surface to about 15cm soil depths, 4 core different samples randomly taken were homogenized in a clean plastic bucket and composited to represent a sample. The representative soil samples (4) were taken to the laboratory, dried, crushed and sieved to remove larger particles. Ten cube of centimeters (10cm3) of 1:3 ratio of HNO3 and HCl was added to 2.0g portion of the soil sample on a hot plate until a clear solution was obtained, the content of the beaker was then allowed to cool. Twenty cube centimeters (20cm3) of distilled water was added and then filtered using filter paper (0.45µm) in 100cm3 volumetric flask. The solution was analyzed for the levels of Cadmium, Lead, Manganese, Copper and Zinc using Atomic Absorption Spectroscopy (AAS) technique. The results obtained showed the following levels for Cd 0.0265 mg/kg, Pb 3.0746 mg/kg, Mn 1.2466mg/kg, Cu, 2.4113 mg/kg and Zn 0.4557 mg/kg respectively for the soil samples from mechanical workshop, while that of control samples was Cd 0.0533mg/kg, Pb 0.1398 mg/kg, Mn, 0.4890 mg/kg, Cu 0.2541 mg/kg and Zn 0.0376 mg/kg respectively. The results of heavy metals obtained from the analysis of soil from the mechanic workshops indicated that their concentrations are relatively higher than that of the control sites but lower than the WHO standard except for manganese which is higher than the WHO standard.

Assessment of the Impact of Industry-Related Air Emission of Arsenic in the Soils of Forest Ecosystems

The soils of forest ecosystems are often affected by the industrial activity of mining and metallurgical enterprises, and insufficiently investigated for the content of pollutants due to enterprise emissions. Some pollutants, such as arsenic, are transported over long distances by these emissions. To analyze this connection, the present study was conducted on the eastern slope of Mount Yurma, the Southern Urals, Russia, to determine the content of arsenic in the soils of mountain forest areas in the impact zone of the copper smelter (Karabash). The physical and chemical parameters, total content of arsenic, mineralogical composition of silt, and concentration of arsenic in the silty fraction in soils located at different altitudes were determined using atomic absorption spectroscopy (AAS) and X-ray diffraction (XRD) techniques. The soils under study are physico-chemically and chemically acidic in the upper horizons with a pH of 3.26 to 4.05. The carbon of organic matter decreases with depth from 7.98 to 0.06%. Exchangeable Ca and Mg cations in the range of 2.6–8.6 mg-eq per 100 g of soil were determined. The mineralogical composition of the silty fraction consists mainly of quartz and aluminosilicates. Following an analysis of the arsenic content in the above-ground leaf litter, the bioconcentration factor (BCF) was calculated. Arsenic exceeding Clarke concentrations was recorded. In all upper soil horizons, concentrations of total arsenic exceeded background values by 3.7–5.2 times, with maximum values in the horizons A—25.3 mg/kg, in the horizons O—64.4 mg/kg. The obtained BCF > 1 data points to the biological arsenic accumulation by plants and, as a result, its input into the soil via industrial emissions from the smelter. It was found that the silty fraction plays a special role in the accumulation of arsenic in the studied soils. Accumulation of arsenic occurred mainly due to the secondary minerals of Ca and Mg. Differences in the accumulation of arsenic in the forest litter depending on the plant association were noted. The obtained results could serve as a guideline for monitoring the areas around the enterprise and enhancing the understanding of pollutants’ distribution in the soils of remote areas and mountain landscapes.

Examination of the transfer of certain elements that are of importance to human health and wine quality in bentonite-model solution system

This scientific research includes sixteen of the most common bentonites on Bulgarian market, which are used by Bulgarian wine cellars in order to achieve colloidal stability of wines. There are bentonites with different composition: sodium, calcium, sodium-calcium, activated calcium, as well as mixtures between natural calcium and activated calcium. Their capacity to transfer elements from and to a model solution with wine parameters have been investigated. Inductively coupled plasma-optical emission spectrometry (ICP-OES), inductively coupled plasma with mass spectrometry (ICP-MS), flame atomic emission spectrometry (FAES) and flame atomic absorption spectrometry (FAAS) techniques have been used. The selected elements, which are subject to this study, are important for human health as well as for the stability of wine clarity.

Imidazolium organometallic complex of palladium on Fe3O4 nanoparticles as selective and magnetically recoverable nanocatalyst for C‐C cross‐coupling reactions

The synthesis of an efficient heterogeneous nanocatalyst was prepared by the anchoring of palladium complex on the surface of an imidazolium‐based ionic liquid‐functionalized Fe3O4 (Pd‐imidazolium@Fe3O4 NPs). The nanocatalyst, Pd‐imidazolium@Fe3O4 NPs, was characterized by Raman, X‐ray diffraction (XRD), thermogravimetric analysis (TGA), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy‐dispersive X‐ray spectroscopy (EDX), fourier transform infrared (FT‐IR), inductively coupled plasma (ICP), and vibrating sample magnetometer (VSM) techniques. The catalytic performance of this novel nanocatalyst was evaluated in the Heck––Mizoroki and Suzuki–Miyaura cross‐coupling reactions under mild conditions using PEG‐400 as a green and biodegradable solvent. The nanocatalyst exhibited high catalytic activity for both cross‐coupling reactions. Furthermore, this stable nanocatalyst can be easily removed and recovered from the reaction mixture and reused for at least eight consecutive cycles without a discernible decrease in the catalytic activity. Also, the recovered Pd‐imidazolium@Fe3O4 NPs was characterized by FT‐IR, XRD, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, and atomic absorption spectroscopy techniques.

Evaluation of the activity and selectivity of mesoporous composites of MCM-41 and CuO in the CO2 photoreduction process

The conversion of CO2 into valuable chemical feedstock through photocatalysis is considered an effective strategy to mitigate global warming and energy supply problems. Among the challenges for CO2 photoreduction are the design and synthesis of active photocatalysts with high affinity for the CO2 molecule and suitable reduction potentials of valence and conduction bands to promote the reduction of the CO2 molecule. Molecular sieves (MCM-41) with semiconductors, such as copper oxide, are alternatives to the traditional semiconductors (TiO2 and ZnO) with high CO2 adsorption capacity, high specific surface area, and good stability, making them perfect candidates for photocatalysis. Therefore, in this work, mesoporous composite materials based on MCM-41 and CuO were synthesized via the impregnation method. The synthesized materials were chemically, structurally, and morphologically characterized by XRD, SEM, FTIR, XPS, DRS, N2 adsorption and desorption, and atomic absorption spectroscopy techniques, and the photocatalytic activity in the reduction of CO2 was evaluated under visible radiation. We show that MCM-41 and the composite MCM-41/CuO have significant potential for use in the CO2 photoreduction process, where the composition and different active sites in the photocatalysts play an important role in the activity and selectivity of the products formed. The results showed that the MCM-41 and the composite with 1 % (w/w%) CuO presented high selectivity and production of methanol, with 585.88 and 267.05 μmol.gcatalyst-1, respectively. Thus, the findings demonstrated the versatility of the MCM-41 to form composites with semiconductors, as well as the need to comprehend the main aspects that influence CO2 photoreduction activities and the selectivity of the composites, including their surface, structural, and electrical features.

Ion Exchange Properties of Crosslinked and Carboxylated Peanut (Arachis Hypogaea L.) Testa Extract

After polymerization via polycondensation of catechin units in the acetone extract of peanut (arachis hypogaea L.) testa (PTE) using phosphorus oxychloride (POCl3) as a crosslinking agent, POCl3-crosslinked PTE (Crosslinked-PPTE) was functionalized by etherification (PC-PTE) using monochloroacetic acid (MCAA) in the presence of an alkali according to the method of Williamson ether synthesis. Subsequent to characterization by Fourier Transform Infrared spectroscopy (FTIR) as well as physical properties, Crosslinked-PPTE was assessed for cation exchange capacity (CEC) and pH at point of zero charge (ZPHC) following demonstrated capacity to remove heavy metal ions in single and multi-elements aqueous solutions by Atomic Absorption Spectrometry (AAS) technique while functionalized (carboxymethylated) Crosslinked-PPTE (PC-PTE) was further characterized by degree of substitution (DS). FTIR absorption bands due to -C-O-P=O, -P=O, P-O-C- and R-O-P-OH stretching vibrations were seen at 1350/1250, 1244/1246, 997/993 cm-1 respectively. Asymmetric and symmetric stretching vibrations of the -C=O of a COOH, Ar-O-C- of an aromatic ether as well as -P-O-C - of an aromatic PO43-, R-P=O of a -PO43-, -R-O-P- and R-O-P-OH of a PO43- ester created by crosslinked and carboxymethylated PTE respectively were seen at 1743, 1377, 1278, 1190, 1062 and 823 cm-1. The results obtained showed that 0.6 was the DS of PC-PTE while 6.72 meq/g and 3.57 defined the CEC and pH (zpc) respectively of Crosslinked-PPTE. Quantitative removal of Fe2+, Ni2+, Pb2+, Cu2+ and Zn2+ in laboratory simulated metal ion wastewater (LSW) to the levels of 84.4, 81.7, 76.5, 72.0 and 75.1% respectively was achieved using Crosslinked-PPTE resin in batch adsorption experiments in which the efficiency was found to depend significantly on the temperature and pH of the water as well as initial adsorbate concentration and contact time but partially on the amount of adsorbent used was observed to be independent of the speed of stirring of the wastewater. Stable, Matakana and fine powder crosslinked-PPTE which is insoluble in water and common laboratory solvents holds great potential in the purification of heavy metal ions polluted water

Development and validation of Graphite Furnace Atomic Absorption Spectrometry method and its application for clinical evaluation of blood lead levels among occupationally exposed lead smelting plant workers.

The growing interest in estimating the blood lead levels, for early detection of lead exposure, warranted a need for a validated analytical method for trace levels estimation of lead. The present study aimed to develop an analytical method for detecting trace amounts to elevated levels of lead in human blood using the Graphite Furnace Atomic Absorption Spectrometry technique and its application in evaluating blood lead levels among occupationally exposed individuals. The method validation was performed with standard test parameters including linearity, recovery, precision, method detection limit, and limit of quantification. The validation results for each performance parameter were in agreement with acceptable criteria as per standard guidelines. The correlation was observed as optimum linear (R2 = 0.998) between absorbance and lead concentration range from 0 to 10µg/dL. The recoveries for spiked samples ranged between 95 and 105%. The calculated value for the method detection limit was 0.16µg/dL and the limit of quantification was 0.51µg/dL. The precision for all spiked concentrations was below 10% of the relative standard deviation. Evaluation of lead exposure among occupationally exposed individuals revealed the study population had found average blood lead level (42.80 ± 12.47µg/dL), which was above the upper acceptable limit suggested by Occupational Safety and Health Administration, USA. The majority of system-specific symptoms were observed among study groups having mean blood lead levels above 40µg/dL. However, sociodemographic status and employment factors were found possible determinants of the prevalence of high blood lead levels.

Comparison of Digestion Methods Using Atomic Absorption Spectrometry for the Determination of Metal Levels in Plants

Trace metal elements (TMEs) are among the most important types of pollutants in the environment. Therefore, a precise determination of these contaminants in several environmental components is required for the safety assurance of living organisms. Spectroscopic analysis is an efficient technique employed to detect and determine TME contents in numerous samples. Hence, to achieve reliable and accurate results when using spectroscopic analysis, samples should be carefully prepared. In the present study, the comparison of eight digestion methods of five vegetal samples was carried out to quantify Cd, Mn, Al and Mg contents using the atomic absorption spectroscopy technique. According to the extraction techniques used in this study, results showed an outstanding difference in TME levels determined in the same vegetal sample. The results obtained indicated that the highest Mn concentrations were recorded when using the mixture of HNO3-HClO4 in the studied species: atriplex portulacoides, arthrocnemum indicum, olea europaea BCR-62, ulva lactuca and ulva lactuca BCR-279 compared to all other methods. Regarding the extraction of Cd, our results showed that heated extraction using different acids (HNO3-H2SO4-HClO4, HCl-HNO3, HNO3-HClO4, HNO3-H2SO4, HNO3-HCl-HClO4 and HNO3-HCl-H2SO4) was the most efficient in atriplex portulacoides, arthrocnemum indicum, olea europaea BCR-62, ulva lactuca and ulva lactuca BCR-279. Similarly, these heated acid digestion techniques (efficient for Cd) showed the highest levels of Al in atriplex portulacoides and arthrocnemum indicum. However, for the Mg extraction, our results revealed that the effectiveness of the method used depended on the plant species studied. Regarding these findings, the efficiency of metal quantification by AAS depends on the digestion procedure, the metallic ion to determine and the plant species.

THE ECOLOGICAL AGRICULTURAL PRODUCTS – SOURCES OF RAW MATERIALS FOR QUALITY FOOD PRODUCTS

Organic agricultural products are the best raw materials for food products with high nutritional density (food supplements, functional foods, and nutraceuticals). The applied technologies in the organic farming system use inputs free of hormones, GMOs, pesticides, antibiotics and other synthetic substances - and all of these allow both the preservation of the bio-availability of the active compounds during processing and the elimination of toxicological risks in final food products. The authors present an innovative approach to the production technology specific to a food product with high nutritional density that is developed from raw materials from Romania. The production of quality foods with high nutritional density can be supported both by Romania's huge potential within the production system specific to ecological agriculture and by the increased demand for such products with added value. The use of special techniques of Atomic Absorption Spectrometry (AAS), extraction of active bio-compounds with the help of supercritical agents (SFE), molecular absorption spectrometry (MAS) facilitates the monitoring of food safety for both raw materials and final foods.

Determination of Heavy Metals in Cocoa Products Consumed in Nairobi County Kenya

Cocoa is an important cash crop obtained from the beans of the Theobroma cacao tree belonging to the family Malvaceae. Its products are rich in several classes of phenolic compounds such as Flavanols, procyanidins, and anthocyanins. These compounds are attributed to copious health benefits. In addition to the bioactive compounds, cocoa contains heavy metals whose origin and levels depend on natural and anthropogenic activities. Beyond permissible limits, these metals are linked to deleterious damage to several systems in the human body. This study aims to determine the concentration of some heavy metals in Cocoa products and compare the levels with the permissible exposure limits stipulated by international health agencies. This was achieved by wet digestion of the strategically sampled cocoa products and their analysis using the atomic absorption spectrometry technique. The average concentration of Lead (Pb), Copper (Cu), Zinc (Zn), and Manganese (Mn) in cocoa powder was 0.154±0.021, 0.270±0.037, 0.794±0.063, and 0.334±0.015 respectively. The average concentration of Pb, Cu, Zn, and Mn in cocoa butter was 0.329±0.008, 0.028±0.038, 0.116±0.075, and 0.124±0.008 respectively. The average concentration of Pb, Cu, Zn, and Mn in chocolate milk was 0.463±0.003, 0.042±0.066, 0.296±0.015, and 0.162±0.010 respectively. Cadmium levels were below the detection limit in all the samples. The results obtained in all the samples were within the WHO and KEBS permissible levels in food products.

A Green Product Using Selective Compound for Susceptible Assessment of Copper in Blood Serum

A highly reliable approach for assessment of copper(II) in blood serum samples using an organic molecule 4-(3-hydroxyphenylazo)resorcinol, 4-HAR was developed. The paper presents the synthesis of 4-HAR, which serves as probe for definite species. 4-HAR was characterized with the FT-IR, UV-visible, 1H-NMR, 13C-NMR and mass analysis, thermal TG and DSC techniques. After examining its interactions with more than twenty-five metal ions, it was found that 4-HAR showed reaction only with copper(II), giving a distinct green color at λmax 603 nm. Experimental conditions for the reaction of 4-HAR with copper(II) were optimized. A calibration curve was created and the exhibition range of concentration obeyed Beer's Law from 0.30 to 16 μg.mL-1 with correlation coefficient of r = 0.9986, and value of the molar absorption coefficient, ε, being 3314 L.mol- 1.cm-1. The analytical method was used to determine copper(II) levels in several blood serum samples. The amounts of copper(II) found in the sera samples were compared with flame atomic absorption spectrometry technique, and the results were found to be highly reliable. Based on validation, the new approach can be utilized for assurance quality purposes with a high degree of confidence.