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result(s) for
"Atomic absorption analysis"
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Automated Microextraction Separation of Lead from Vegetable Oils for Determination by Atomic Absorption Spectrometry
2024
Hydrophilic deep eutectic solvents based on choline chloride, carboxylic acids, and water are studied as “green” extractants for the liquid–liquid microextraction of lead from vegetable oils. An automated method is proposed for the microextraction of lead from vegetable oils into a ternary deep eutectic solvent based on choline chloride, lactic acid, and water. The carboxylic acid in the extractant ensured the effective mass transfer of lead due to complexation. Water in the extractant made it possible to reduce its viscosity to automate liquid–liquid microextraction. The analytical capabilities of the developed method are demonstrated on an example of determining lead in vegetable oils by atomic absorption spectrometry with electrothermal atomization. The limit of detection (3σ) for lead is 0.3 μg/kg. The developed method does not require sample mineralization.
Journal Article
Platinum Concentration and Pathologic Response to Cisplatin-Based Neoadjuvant Chemotherapy in Muscle-Invasive Bladder Cancer
by
Guancial, Elizabeth A.
,
Kim, Eric S.
,
Abu-Farsakh, Sohaib H.
in
Accumulation
,
Adjuvant chemotherapy
,
Aged
2016
Platinum (Pt)-based chemotherapy is the standard of care for muscle-invasive bladder cancer (MIBC). However, resistance is a major limitation. Reduced intratumoral drug accumulation is an important mechanism of platinum resistance. Our group previously demonstrated a significant correlation between tissue Pt concentration and tumor response to Pt-based neoadjuvant chemotherapy (NAC) in lung cancer. We hypothesized that increased Pt concentration in radical cystectomy (RC) specimens would correlate with improved pathologic response to Pt-based NAC in MIBC.
A cohort of 19 clinically annotated, archived, fresh frozen RC specimens from patients with MIBC treated with Pt-based NAC was identified [ypT0 (pathologic complete response, pCR), N = 4; ≤ypT1N0M0 (pathologic partial response, pPR), N = 6; ≥ypT2 (minimal pathologic response/progression), N = 9)]. RC specimens from 2 patients with MIBC who did not receive NAC and 1 treated with a non-Pt containing NAC regimen were used as negative controls. Total Pt concentration in normal adjacent urothelial tissue and bladder tumors from RC specimens was measured by flameless atomic absorption spectrophotometry.
Total Pt concentration in normal urothelium differed by tumor pathologic response (P = 0.011). Specimens with pCR had the highest Pt concentrations compared to those with pPR (P = 0.0095) or no response/progression (P = 0.020). There was no significant difference in Pt levels in normal urothelium and tumor between pPR and no response/progression groups (P = 0.37; P = 0.25, respectively).
Our finding of increased intracellular Pt in RC specimens with pCR following NAC for MIBC compared to those with residual disease suggests that enhanced Pt accumulation may be an important determinant of Pt sensitivity. Factors that modulate intracellular Pt concentration, such as expression of Pt transporters, warrant further investigation as predictive biomarkers of response to Pt-based NAC in MIBC.
Journal Article
Phytoremediation of toxic metals present in soil and water environment: a critical review
by
Rani, Lata
,
Kanwar, Varinder Singh
,
Sharma, Ajay
in
Activation analysis
,
Aquatic Pollution
,
Atmospheric Protection/Air Quality Control/Air Pollution
2020
Heavy metals are one of the most hazardous inorganic contaminants of both water and soil environment composition. Normally, heavy metals are non-biodegradable in nature because of their long persistence in the environment. Trace amounts of heavy metal contamination may pose severe health problems in human beings after prolonged consumption. Many instrumental techniques such as atomic absorption spectrophotometry, inductively coupled plasma-mass spectrometry, X-ray fluorescence, neutron activation analysis, etc. have been developed to determine their concentration in water as well as in the soil up to ppm, ppb, or ppt levels. Recent advances in these techniques along with their respective advantages and limitations are being discussed in the present paper. Moreover, some possible remedial phytoremediation approaches (phytostimulation, phytoextraction, phyotovolatilization, rhizofiltration, phytostabilization) have been presented for the removal of the heavy metal contamination from the water and soil environments.
Journal Article
Specialized Methods of Thermal Treatment of Riverine and Marine Suspensions Preparatorily to Their Analysis for Trace Concentrations of Chemical Elements
2018
The paper considerations of the possibility of the low-temperature (1000°C) and high-temperature (>1500°C) thermal decomposition of solid samples of suspensions and the selective fractional evaporation–condensation of elements in specialized electrothermal crucible and rod atomizers for the purposes of direct atomic-absorption analysis. The approach is applied to analyze samples of riverine and marine suspensions for Ag, Cd, and Tl.
Journal Article
Determination of Pb (Lead), Cd (Cadmium), Cr (Chromium), Cu (Copper), and Ni (Nickel) in Chinese tea with high-resolution continuum source graphite furnace atomic absorption spectrometry
2016
The contents of lead, cadmium, chromium, copper, and nickel were determined in 25 tea samples from China, including green, yellow, white, oolong, black, Pu'er, and jasmine tea products, using high-resolution continuum source graphite furnace atomic absorption spectrometry. The methods used for sample preparation, digestion, and quantificational analysis were established, generating satisfactory analytical precisions (represented by relative standard deviations ranging from 0.6% to 2.5%) and recoveries (98.91–101.32%). The lead contents in tea leaves were 0.48–10.57 mg/kg, and 80% of these values were below the maximum values stated by the guidelines in China. The contents of cadmium and chromium ranged from 0.01 mg/kg to 0.39 mg/kg and from 0.27 mg/kg to 2.45 mg/kg, respectively, remaining in compliance with the limits stipulated by China's Ministry of Agriculture. The copper contents were 7.73–63.71 mg/kg; only 64% of these values complied with the standards stipulated by the Ministry of Agriculture. The nickel contents ranged from 2.70 mg/kg to 13.41 mg/kg. Consequently, more attention must be paid to the risks of heavy metal contamination in tea. The quantitative method established in this work lays a foundation for preventing heavy metal toxicity in human from drinking tea and will help establish regulations to control the contents of heavy metals in tea.
Journal Article
Toxicity evaluation of textile effluents and role of native soil bacterium in biodegradation of a textile dye
2018
Water pollution caused by the discharge of hazardous textile effluents is a serious environmental problem worldwide. In order to assess the pollution level of the textile effluents, various physico-chemical parameters were analyzed in the textile wastewater and agricultural soil irrigated with the wastewater (contaminated soil) using atomic absorption spectrophotometer and gas chromatography-mass spectrometry (GC-MS) analysis that demonstrated the presence of several toxic heavy metals (Ni, Cu, Cr, Pb, Cd, and Zn) and a large number of organic compounds. Further, in order to get a comprehensive idea about the toxicity exerted by the textile effluent, mung bean seed germination test was performed that indicated the reduction in percent seed germination and radicle-plumule growth. The culturable microbial populations were also enumerated and found to be significantly lower in the wastewater and contaminated soil than the ground water irrigated soil, thus indicating the biotic homogenization of indigenous microflora. Therefore, the study was aimed to develop a cost effective and ecofriendly method of textile waste treatment using native soil bacterium, identified as
Arthrobacter soli
BS5 by 16S rDNA sequencing that showed remarkable ability to degrade a textile dye reactive black 5 with maximum degradation of 98% at 37 °C and pH in the range of 5–9 after 120 h of incubation.
Journal Article
Quantitative assessment on soil concentration of heavy metal–contaminated soil with various sample pretreatment techniques and detection methods
2020
Detection and quantification of heavy metals in soil samples are significant in terms of environmental monitoring and risk assessment for metals. In order to improve the accuracy and precision to detect heavy metal, in this study, four standard samples (NASS-4, NASS-5, NASS-9, and NASS-16) were analyzed by evolving heating (electric heating plate, water bath, and microwave) and acidic systems (includes HCl, HNO
3
, HF, and HClO
4
). The result shows that different pretreatment methods have different effects on the extraction of heavy metal elements and five heavy metal elements (Cu, Zn, Pb, Ni, and Cr) were selected for optimization through pretreatment methods. Although the contents of heavy metals were same but we found diversity in the results. Under optimal conditions, the selected standard samples were analyzed by inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled plasma atomic emission spectroscopy (ICP-AES), and atomic absorption spectroscopy (AAS), and the results were compared. The results show that different elements have their own most suitable detection methods, such as for Pb, the most suitable method is ICP-MS; and for Zn, the most suitable method is AAS. Pretreatment methods and detection techniques are combined to find and improve accuracy of results for certain elements. This study provides a reliable detection method for the accurate detection of heavy metals in the environment.
Journal Article
Potential health risk and levels of heavy metals in water resources of lead–zinc mining communities of Abakaliki, southeast Nigeria
by
Obasi Philip Njoku
,
Akudinobi Bennard Benedict
in
Abandoned mines
,
Alzheimer's disease
,
Analytical methods
2020
Heavy metals are potential health risk, especially in mining sites where they deteriorate from sulfide-rich ore bodies. Lead, cadmium, arsenic and mercury are very carcinogenic, while others are toxic. The assessment of the levels of these metals in water resources of the lead–zinc mining communities of Enyigba, Mkpuma Akpatakpa, Ameka, Amorie, Amanchara and Alibaruhu was carried out, and the potential health risk has been investigated. These areas make up the main mining communities of Abakaliki, where active and abandoned mines are located. One hundred and six water samples were analyzed in two seasons using atomic absorption spectrophotometric and ultra-violet/visible spectroscopy. Result indicates levels of Pb2+ > Hg2+ > As2+ > Cd2+ > Mn2+ > Ag2+ > Se2+ > Ni2+ > Cr2+ > Cu2+ in water sources. High levels of Mn2+(63.45 mg/L), Pb2+(11.42 mg/L), Cr3+(14.60 mg/L), Ni2+(1.260), Cd2+(15.67 mg/L), Ag+(6.06 mg/L), Hg2+(2.60 mg/L), As(4.13 mg/L), Se2+(2.68 mg/L), Zn2+(10.53 mg/L) and Co2+(0.9 mg/L) above the WHO recommended standard for drinking water were observed. Only Cu2+ recorded safe concentrations in 100% samples analyzed. Levels of associated metals including Pb2+, As, Hg2+, Se2+ and Cd2+ are higher in groundwater especially in areas close to the active mines; this is due to mineralization in the area. Seasonal analysis shows a decreased concentration of chemical constituents in the rainy season relative to the dry season. Potential health risk is associated with accumulation of toxic heavy metals in tissues including Parkinson disease, arsenicosis, acrodynia, selenoises, Alzheimer’s disease, hair loss, mental imbalance and abortion in women abound in the areas. Alternative water supply sources and sensitization on the potential health risk are highly advocated in these communities.
Journal Article
Quantification of Heavy Metals and Pesticide Residues in Widely Consumed Nigerian Food Crops Using Atomic Absorption Spectroscopy (AAS) and Gas Chromatography (GC)
by
Okonkwo, Finbarr
,
Rasaq, Waheed A.
,
Okpala, Charles Odilichukwu R.
in
Absorption spectroscopy
,
Aldrin
,
Arsenic
2021
More still needs to be learned regards the relative contamination of heavy metals and pesticide residues, particularly those found in widely consumed Nigerian food crops like cereals, vegetables, and tubers. In this current study, the heavy metals and pesticide residues detectable in widely consumed Nigerian food crops were respectively quantified using atomic absorption spectroscopy (AAS) and gas chromatography (GC). Specifically, the widely consumed Nigerian food crops included cereals (rice, millet, and maize), legume (soybean), tubers (yam and cassava), as well as leaf (fluted pumpkin, Amaranthus leaf, waterleaf, and scent leaf) and fruit vegetables (okro, cucumber, carrot, and watermelon). Results showed that the detected heavy metals included arsenic (As), cadmium (Cd), chromium (Cr), cobalt (Co), iron (Fe), lead (Pb), manganese (Mn), mercury (Hg), and nickel (Ni), whereas the pesticide residues included Aldrin, Carbofuran, g-chlordane, Chlorpyrifos, DichloroBiphenyl, Dichlorodiphenyldichloroethane (DDD), Dichlorodiphenyltrichloroethane (DDT), Dichlorvos, Endosulfan, Heptachlor, Hexachlorobenzene (HCB), Isopropylamine, Lindane, t-nonachlor, and Profenofos. Across the studied food crops, the concentrations of heavy metals and pesticides were varied, with different trends as they largely fell below the established maximum permissible limits, and with some exceptions. Our findings suggest there could be a somewhat gradual decline in the concentration of the heavy metals and pesticide residues of these studied food crops when compared to previously published reports specific to Nigeria. To help substantiate this observation and supplement existing information, further investigations are required into the concentration of these heavy metals and pesticide residues specific to these studied food crops at other parts of the country.
Journal Article
Trace Element and Heavy Metal Levels in Colorectal Cancer: Comparison Between Cancerous and Non-cancerous Tissues
by
Khoonsari, Mahmood Reza
,
Kohi, Zahra
,
MohammadHossein Hosseini Azar
in
Absorption spectroscopy
,
Aetiology
,
Aluminium
2018
Cases of colorectal cancer (CRC) have increased dramatically in Middle Eastern and other Asian countries. Many studies indicate an important role of environmental factors, including trace elements as an etiology of cancer. This study aims to assess the concentration of eight trace elements in cancerous and adjacent non-cancerous tissues in case of CRC. In a cross-sectional study, conducted between March 2015 and February 2016, zinc (Zn), chromium (Cr), manganese (Mn), tin (Sn), copper (Cu), aluminum (Al), lead (Pb), and iron (Fe) levels were evaluated among patients suffering from CRC. All the patients underwent a full colonoscopy. Multiple samples were taken from cancerous lesions and adjacent healthy tissues that kept a minimum distance of 10 cm from the lesions. These specimens were kept at −80 °C. The classic flame atomic absorption spectroscopy (FAAS) method was applied in this study. The mean age of the study population was 55.6 ± 12.8. The median of Zn, Cr, Cu, Al, and Pb in cancerous tissues was significantly higher than that of healthy tissues (P < 0.05). Nevertheless, the median of Mn, Sn, and Fe was significantly lower than that of non-cancerous tissues (P < 0.05). Between colon and rectal specimens, we did not find a difference between Cr and Al levels and Zn, Sn, and Cu levels in cancerous and healthy tissues, respectively. We revealed that gender and history of smoking may influence the level of some trace elements. We revealed that the levels of eight elements were significantly different for cancerous and healthy tissues. This may play a role in developing CRC. These findings reflect the importance of environmental pollution in this setting.
Journal Article