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1.
Bull Environ Contam Toxicol ; 113(4): 39, 2024 Sep 06.
Article in English | MEDLINE | ID: mdl-39242363

ABSTRACT

Phytoremediation is a rapidly expanding process due to its technical and economic viability. The objective of this work was to evaluate the phytoremediation potential of Helianthus annuus in three cultivation media: artificially contaminated Catalão soil, hydroponics and roadside soil. In hydroponics, ZnCl2 doses 0.32 mgL- 1, 29.94 mgL- 1, 60.06 mgL- 1, 119.94 mgL- 1 were used. While in the artificially contaminated soil, the doses were 0 mgkg- 1, 299 mgkg- 1, 599 mgkg- 1, 1498 mgkg- 1. Physiological analyzes made it possible to demonstrate that treatments T3 and T4, with the highest concentrations of the metal, inhibited growth and promoted darkening of the roots. The highest Zn contents occurred in the aerial part. The results indicated that Helianthus annuus was classified as hyperaccumulator due to its ability to accumulate high levels of Zn mainly in artificially contaminated soil.


Subject(s)
Biodegradation, Environmental , Helianthus , Soil Pollutants , Tropical Climate , Zinc , Helianthus/metabolism , Soil Pollutants/metabolism , Soil Pollutants/analysis , Zinc/metabolism , Plant Roots/metabolism , Hydroponics
2.
ACS Omega ; 9(34): 36835-36846, 2024 Aug 27.
Article in English | MEDLINE | ID: mdl-39220530

ABSTRACT

Since 1970 acyclovir (ACV) has been the reference drug in treating herpes simplex virus (HSV) infections. However, resistant herpes simplex virus type 1 (HSV-1) strains have emerged, narrowing the treatment efficacy. The antiviral activity of classical Na+, K+ ATPase enzyme (NKA) inhibitors linked the viral replication to the NKA's activity. Herein, we evaluated the anti-HSV-1 activity of synthetic naphthoquinones, correlating their antiviral activity with NKA inhibition. We tested seven synthetic naphthoquinones initially at 50 µM on HSV-1-infected African green monkey kidney cells (VERO cells). Only one compound, 2-hydroxy-3-(2-thienyl)-1,4-naphthoquinone (AN-06), exhibited higher antiviral activity with a low cytotoxicity. AN-06 reduced the viral titer of 9 (log10) to 1.32 (log10) and decreased the steps of attachment and penetration. The addition of AN-06 up to 20 h postinfection (hpi) interfered with the viral cycle. The viral infection alone increases NKA activity 3 h postinfection (hpi), scaling up to 6 hpi. The addition of AN-06 in a culture infected with HSV-1 decreased NKA activity, suggesting that its antiviral action is linked to NKA inhibition. Also, docking results showed that this compound binds at the same site of NKA in which adenosine triphosphate (ATP) binds. AN-06 exhibited promising pharmacokinetic and toxicology properties. Thus, we postulate that AN-06 may be a good candidate for antiviral compounds with a mechanism of action targeting NKA activity.

3.
J AOAC Int ; 107(5): 790-794, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-38964346

ABSTRACT

BACKGROUND: Understanding the chemical composition of fluorescent lamp residue, particularly potentially toxic elements, is crucial for reducing environmental impacts and human health risks after disposal. However, the challenge lies in effectively analyzing these heterogeneous solid samples. Techniques involving quantitative dissolution become imperative, playing a fundamental role in quantifying trace elements. OBJECTIVE: The aim of this work is to develop and present a new, faster, and more efficient and environmentally friendly method using ultrasound-assisted acid extraction to quantify potentially toxic elements (Cu, Mn, Ni, Sr, and Zn) present in fluorescent lamp waste using the inductively coupled plasma-optical emission spectrometry technique. METHODS: An ultrasound-assisted acid extraction method for the quantification of potentially toxic elements in fluorescent lamp waste was developed and applied as a greener alternative to conventional digestion methods. For variable optimization, a full factorial design with two levels and two variables (time and temperature) was used to determine which factors significantly affected the observed response. RESULTS: The results obtained for the developed extraction method were compared with a reference method employing a heating acid digestion (with a mixture of HCl, HClO4, and HF) using statistical tools. The best results were obtained using an extraction time of 10 min and a temperature of 25°C. Inductively coupled plasma optical emission spectrometry was applied for element quantification. CONCLUSION: The proposed extraction method showed good results for Cu, Mn, Ni, Sr, and Zn. Furthermore, the proposed method based on ultrasound radiation presents additional criteria that align with the concepts of green analytical chemistry. HIGHLIGHTS: A greener alternative method for the determination of Cu, Mn, Ni, Sr, and Zn in fluorescent lamp waste was developed. Optimal conditions for ultrasound extraction of potentially toxic elements were achieved in 10 min at a temperature of 25°C. Environmentally friendly aspects of ultrasound align with the requirements of green analytical chemistry.


Subject(s)
Green Chemistry Technology , Green Chemistry Technology/methods , Spectrophotometry, Atomic/methods , Ultrasonics , Trace Elements/analysis , Trace Elements/isolation & purification
4.
Foods ; 13(14)2024 Jul 09.
Article in English | MEDLINE | ID: mdl-39063253

ABSTRACT

Plant-based milk has gained considerable attention; however, its high nutritional variation highlights the need for improved formulation designs to enhance its quality. This study aimed to nutritionally compare cow milk with plant-based milk produced from hazelnuts (H), Brazil nuts (BN), cashew nuts (CN), soybeans (S), and sunflower seeds (SS), and to perform physicochemical and technological characterization. The plant-based milk produced with isolated grains showed a nutritional composition inferior to that of cow milk in almost all evaluated parameters, protein content (up to 1.1 g 100 g-1), lipids (up to 2.7 g 100 g-1), color parameters, minerals, and especially calcium (up to 62.4 mg L-1), which were originally high in cow milk (up to 1030 mg L-1). However, the plant-based milk designed using a blend composition was able to promote nutritional enhancement in terms of minerals, especially iron (Fe) and magnesium (Mg), high-quality lipids (up to 3.6 g 100 g-1), and carbohydrates (3.4 g 100 g-1 using CN, BN, and S). The protein content was 1.3% compared to 5.7 in cow milk, and the caloric value of plant-based milk remained 32.8 at 52.1 kcal, similar to cow milk. Satisfactory aspects were observed regarding the shelf life, especially related to microbiological stability during the 11 d of storage at 4 °C. For the designed plant-based milk to be equivalent to cow milk, further exploration for optimizing the blends used to achieve better combinations is required. Furthermore, analyzing possible fortification and preservation methods to increase shelf life and meet the nutritional and sensory needs of the public would be interesting.

5.
Chemosphere ; 361: 142481, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38823428

ABSTRACT

The study presents the successful development of a new electrochemical sensor with low cost and disposability for application in nitrofurazone detection in environmental and pharmaceutical samples. The sensors were fabricated using materials obtained from local storage and conductive carbon ink. The modification of the screen-printed electrodes with the hybrid nanomaterial based on silver nanoparticles, carbon quantum dots, and carbon nanotubes showed synergistic contributions in the nitrofurazone electrooxidation, as observed in the wide linear range (0.008 at 15.051 µM), with a sensitivity of 0.650 µA/µM. The limit of detection obtained was 4.6 nM. Differential pulse voltammetry, cyclic voltammetry, X-ray photoelectron spectroscopy, X-ray diffraction analysis, and high-resolution transmission electron microscopy were used to evaluate the electrochemical and structural characteristics. Studies of possible interferences were considered with nitrofurazone in the presence of the ions and organic molecules. The results were satisfactory, with a variation of 93.3% ± 4.39% at 100% ± 2.40%. The low volume used in the analyses (50 µL), disposability, high sensibility, selectivity, and low limit of detection are advantages that make the proposed sensor an electrochemical tool of high viability for the NFZ detection in environmental matrices and pharmaceutical formulations.


Subject(s)
Anti-Bacterial Agents , Electrochemical Techniques , Metal Nanoparticles , Nanotubes, Carbon , Nitrofurazone , Nitrofurazone/analysis , Nitrofurazone/chemistry , Electrochemical Techniques/methods , Nanotubes, Carbon/chemistry , Metal Nanoparticles/chemistry , Anti-Bacterial Agents/analysis , Limit of Detection , Silver/chemistry , Electrodes , Quantum Dots/chemistry
6.
Eur J Clin Nutr ; 78(9): 801-807, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38909172

ABSTRACT

BACKGROUND/OBJECTIVES: Sickle cell anemia (SCA) is marked by hypoxia, inflammation, and secondary iron overload (IO), which potentially modulate hepcidin, the pivotal hormone governing iron homeostasis. The aim was to evaluate the iron incorporation in red blood cells (RBC) in SCA pediatric patients, considering the presence or absence of IO. SUBJECTS/METHODS: SCA children (n = 12; SCAtotal) ingested an oral stable iron isotope (57Fe) and iron incorporation in RBC was measured after 14 days. Patients with ≥1000 ng/mL serum ferritin were considered to present IO (SCAio+; n = 4) while the others were classified as being without IO (SCAio-; n = 8). Liver iron concentration (LIC) was determined by Magnetic Resonance Imaging (MRI) T2* method. RESULTS: The SCAio+ group had lower iron incorporation (mean ± SD: 0.166 ± 0.04 mg; 3.33 ± 0.757%) than SCAio- patients (0.746 ± 0.303 mg; 14.9 ± 6.05%) (p = 0.024). Hepcidin was not different between groups. Iron incorporation was inversely associated with serum ferritin level (SCAtotal group: r = -0.775, p = 0.041; SCAio- group: r = -0.982; p = 0.018) and sickle hemoglobin (HbS) presented positive correlation with iron incorporation (r = 0.991; p = 0.009) in SCAio- group. LIC was positively associated with ferritin (SCAtotal: r = 0.921; p = 0.026) and C reactive protein (SCAio+: r = 0.999; p = 0.020). CONCLUSION: SCAio+ group had lower iron incorporation in RBC than SCAio- group, suggesting that they may not need to reduce their intake of iron-rich food, as usually recommended. Conversely, a high percentage of HbS may indirectly exacerbate hypoxia and seems to increase iron incorporation in RBC. TRIAL REGISTRATION: This trial was registered at www.ensaiosclinicos.gov.br . Identifier RBR-4b7v8pt.


Subject(s)
Anemia, Sickle Cell , Erythrocytes , Ferritins , Hepcidins , Iron Isotopes , Iron Overload , Iron , Humans , Anemia, Sickle Cell/blood , Pilot Projects , Erythrocytes/metabolism , Child , Male , Female , Ferritins/blood , Iron/blood , Iron/metabolism , Iron Overload/blood , Adolescent , Hepcidins/blood , Liver/metabolism
7.
Eur J Nutr ; 63(6): 2163-2172, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38722385

ABSTRACT

PURPOSE: Iron absorption in sickle cell anemia (SCA) remains unclear and studies in adults with SCA are scarce. The aim of this study was to evaluate the iron absorption SCA adults and its association with iron status and hepcidin concentration. METHODS: SCA patients (n = 13; SCAtotal) and control participants (n = 10) ingested an oral stable iron isotope (57Fe). Iron absorption was measured by inductively coupled plasma mass spectrometry (ICP-MS) 14 days after isotope administration. Patients with ≥ 1000 ng/mL serum ferritin were considered to present iron overload (IO) (SCAio+; n = 3) and others classified without IO (SCAio-; n = 10). RESULTS: Iron absorption in the control group ranged from 0.3 to 26.5% (median = 0.9%), while it varied from 0.3 to 5.4% in SCAio+ (median = 0.5%) and from 0.3 to 64.2% in the SCAio- (median = 6.9%). Hepcidin median values were 14.1 ng/mL (3.0-31.9 ng/mL) in SCAio-, 6.2 ng/mL (3.3-7.8 ng/mL) in SCAio + and 6.2 ng/mL (0.6-9.3 ng/mL) in control. Iron absorption was associated with ferritin level (r = - 0.641; p = 0.018) and liver iron concentration (LIC; r = - 0.786; p = 0.036) in the SCAtotal group. CONCLUSION: Our data suggest that SCAio- individuals may be at risk of developing primary IO. Simultaneously, secondary IO may induce physiological adaptation, resulting in reduced iron absorption. Further studies evaluating intestinal iron absorption using larger sample sizes should be conducted to help establish a safe nutrition approach to be adopted and to ensure the security of food-fortifying public policies for these patients. TRIAL REGISTRATION: This trial was registered at www.ensaiosclinicos.gov.br (Identifier RBR-4b7v8pt).


Subject(s)
Anemia, Sickle Cell , Hepcidins , Intestinal Absorption , Iron Isotopes , Humans , Anemia, Sickle Cell/blood , Adult , Male , Female , Iron Isotopes/pharmacokinetics , Hepcidins/blood , Young Adult , Ferritins/blood , Iron/blood , Iron/pharmacokinetics , Iron/metabolism , Iron Overload , Iron, Dietary/pharmacokinetics , Iron, Dietary/administration & dosage , Middle Aged , Nutritional Status
8.
Environ Sci Pollut Res Int ; 31(16): 24163-24179, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38436860

ABSTRACT

Coastal sedimentary systems are affected by continental and marine metal pollutant inputs associated with different hydrodynamic characteristics and geochemical processes. These include the formation of acid-volatile sulfides (AVS) within sediments, which affects metal bioavailability and associated aquatic biota toxicity risks. Physicochemical changes in these environments in the face of extreme natural or man-made environmental influences can dramatically alter metal bioavailability and toxicity through metal binding and immobilization as insoluble sulfides. Surface sediments from Guanabara Bay, river mouths, and two mangrove areas were collected, and AVS and simultaneously extracted metals Cd, Cu, Fe, Mn, Ni, Pb, and Zn and ΣSEM were determined to assess sediment quality. A severe eutrophication history favored AVS concentrations exceeding or close to the sum-SEM concentrations, demonstrating that AVS play an important role in making trace metals unavailable for assimilation by living organisms, mitigating the risks of contamination for the local biota. This eutrophication-driven sulfide accumulation may attenuate the sediment toxicity in sites heavily polluted by metals, while some fewer eutrophic sites became more exposed to metals in excess to AVS.


Subject(s)
Metals, Heavy , Trace Elements , Water Pollutants, Chemical , Acids , Bays , Environmental Monitoring , Geologic Sediments/chemistry , Metals/analysis , Metals, Heavy/analysis , Sulfides/chemistry , Water Pollutants, Chemical/analysis
9.
Talanta ; 270: 125579, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38150969

ABSTRACT

Iron is an essential element for human life and its nutritional status in the human body is directly linked to human health. More than 1015 atoms of iron per second are necessary for the maintenance of haemoglobin formation. To predict iron bioavailability three approaches are normally employed: (a) faecal recovery; (b) plasma appearance; and (c) erythrocyte incorporation (the most used). Isotope Pattern Deconvolution (IPD) is a mathematical tool that allows the isolation of distinct isotope signatures from mixtures of natural abundance and enriched tracers. In this work we propose a novel strategy to assess erythrocyte iron incorporation, based on the use of an iron stable isotope (57Fe) and the IPD concept. This strategy allows direct calculation of the exogenous concentration of 57Fe incorporated into RBCs after supplementation. In this way, to determine the mass of iron incorporated into erythrocytes, the unique prediction that must be made is the blood volume, estimate to reproduce the natural dilution of the tracer (57Fe) in the blood. This novel bioanalytical approach was applied for the measurements of iron incorporation and further iron absorption studies in humans, using a group of twelve healthy participants, that should be further evaluated for the assessment of other chemical elements that could be of health concerns and directly impact society.


Subject(s)
Erythrocytes , Iron , Humans , Iron/metabolism , Iron Isotopes/metabolism , Erythrocytes/metabolism , Plasma , Biological Availability
10.
Drug Test Anal ; 15(11-12): 1392-1402, 2023.
Article in English | MEDLINE | ID: mdl-37641464

ABSTRACT

Cobalt was included on the World Anti-Doping Agency Prohibited List in 2015 due to its effect on stimulus of erythropoiesis via stabilization of hypoxia-inducible factor. Although it has proven benefits for performance enhancement, the unavailability of inductively coupled plasma-mass spectrometry on routine of the accredited laboratories is a factor that reduces its applicability in anti-doping analysis. Therefore, an analytical method for quantification of urinary cobalt as its diethyldithiocarbamate complex by liquid chromatography coupled with high-resolution tandem mass spectrometry was developed and validated. Palladium was proposed as internal standard and rhodium as a complexation control. A microwave-assisted acid digestion of the urine samples was essential, not only to eliminate the matrix effect but mainly to avoid the non-specific bond of cobalt to endogenous molecules. A linear method was obtained over the studied range from a negative urine control to a spiked concentration of 25 ng/mL, with an estimated limit of quantification of 2.5 ng/mL, and an adequate combined standard uncertainty of 11.4%. Considering that all reagents are commercially available, the proposed strategy is feasible to be included on routine sample preparation. Monitoring urinary cobalt concentrations globally opens the perspective to support the anti-doping system to define a suitable threshold value and to understand its potential misuse by athletes seeking for performance improvement.


Subject(s)
Body Fluids , Doping in Sports , Humans , Tandem Mass Spectrometry/methods , Cobalt/urine , Chromatography, Liquid/methods , Specimen Handling , Substance Abuse Detection/methods
11.
Anal Methods ; 15(31): 3874-3884, 2023 08 10.
Article in English | MEDLINE | ID: mdl-37498592

ABSTRACT

This study presents the development of an electrochemical sensor, denoted as GCE/CB/SiAlSn, based on the modification of a glassy carbon electrode surface with the ternary oxide SiO2/Al2O3/SnO2 associated with carbon black, for direct determination of the neonicotinoid pesticide clothianidin in different matrices, such as environmental and food samples. Morphological characterization by the scanning electron microscopy technique, electroanalytical analyses using the cyclic voltammetry technique and differential pulse voltammetry are presented which demonstrated that the developed electrochemical platform presents high sensitivity in the electroanalytical clothianidin determination. The linear range studied was from 2.99 × 10-7 to 6.04 × 10-5 mol L-1, with an LOD of 2.47 nmol L-1. This high sensitivity was explained using the synergistic relationship between carbon black and ternary oxide that maximized the electroactive surface area of the GCE/CB/SiAlSn sensor. Interferent studies were performed that showed high selectivity of the sensor to the pesticide in the presence of Ca2+, K+, Na+, and Mg2+ and carbendazim, glyphosate, imidacloprid and thiamethoxam pesticides. The sensor was applied to real samples of tap water and apple juice obtaining recoveries from 91.0% to 103.0%.


Subject(s)
Graphite , Oxides , Oxides/chemistry , Graphite/chemistry , Soot , Silicon Dioxide , Neonicotinoids
12.
Environ Monit Assess ; 195(6): 691, 2023 May 19.
Article in English | MEDLINE | ID: mdl-37204496

ABSTRACT

The metal contamination and the degradation of polyethylene terephthalate (PET) due to human activities have contributed to the worsening of environmental problems in aquatic systems. Therefore, the study aimed to evaluate PET microplastic adsorption levels when exposed to high amounts of Ni, Cu and Co. The PET microplastic was characterized by scanning electron microscopy, Brunner-Emmet-Teller, porosimetry system, Barrett-Joyner-Halenda and Fourier transform infrared spectroscopy with attenuated total reflectance for evaluation of surface morphology, surface area, porosity, pore size and functional groups, respectively. The results showed that the surface area, the presence of macro and mesopores, and the functional groups influence the adsorption of metals on the surface of PET microplastic. The adsorption isotherms confirmed the presence of mesoporosity and macroporosity on the PET microplastic surface. The Freundlich and Langmuir models were used to study the adsorption capacity. The kinetics of adsorptions were interpreted using pseudo-first order and pseudo-second order models. The results indicated that the Langmuir isotherm and the pseudo-second order adequately described the adsorption of metals by the PET microplastic. The removal rates by the PET microplastic varied from 8 to 34% for Ni, 5 to 40% for Cu and 7 to 27% for Co after a period of 5 days. Furthermore, the adsorption was predominantly chemical and extremely fast, indicating that the presence of microplastics in the environment can lead to a rapid metal accumulation which elevates the hazards potential of microplastic in living beings.


Subject(s)
Microplastics , Water Pollutants, Chemical , Humans , Plastics , Water Pollutants, Chemical/analysis , Environmental Monitoring , Metals , Spectroscopy, Fourier Transform Infrared , Kinetics , Adsorption , Hydrogen-Ion Concentration
13.
Molecules ; 27(22)2022 Nov 17.
Article in English | MEDLINE | ID: mdl-36432079

ABSTRACT

Soybean meal (SBM) is a co-product of the soybean oil industry that is rich in bioactive compounds, such as isoflavones. We aimed to study the effects of processing SBM by fermentation (Saccharomyces cerevisiae) (FSBM) and enzymatic hydrolysis (CelluMax C, a commercial cellulase) (ESBM) on its chemical composition, with emphasis on isoflavones. Fermentation increased protein content by 9%, ash content by 7%, dietary fiber by 11% and minerals by up to 38%, except for iron, which decreased by 26%. Fermentation completely removed oligosaccharides from SBM, while enzymatic processing decreased oligosaccharides by 45% in SBM. Both processes converted glycosylated isoflavones into the corresponding aglycones, the content of which increased by up to 7.7-fold. Biscuits containing SBM, FSBM and ESBM could be labeled as dietary sources of dietary fibers, potassium, phosphorous, calcium and zinc, as well as high in proteins, copper, iron, manganese and magnesium. While FSBM biscuits had lower sensory scores compared to SBM biscuits, ESBM biscuits had equivalent scores. During storage for 180 days at room temperature, the isoflavone profile of all biscuits remained stable. Moreover, storage did not impair microbiological and sensory qualities of any biscuits. Altogether, ESBM biscuits show great marketing potential.


Subject(s)
Fabaceae , Isoflavones , Glycine max , Dietary Fiber , Iron
14.
Mikrochim Acta ; 189(8): 307, 2022 08 02.
Article in English | MEDLINE | ID: mdl-35917034

ABSTRACT

The study aimed to develop an electrochemical sensor based on glassy carbon, mixed oxide (SiO2/TiO2/Sb2O5), and carbon black. The material was synthesized, characterized, and used to determine thiamethoxam in raw honey and water. The morphologic structure and electrochemical performance of the sensor was characterized by scanning electron microscopy and cyclic voltammetry. Differential pulse voltammetry with a concentration of 0.1 mol L-1 of Britton-Robinson buffer at pH 7.0 allowed the generation of a method to determine thiamethoxam in a linear range of 0.25 to 100.5 µmol L-1 and with a limit of detection of 0.012 µmol L-1. The system efficiently quantified traces of thiamethoxam in raw honey and tap water samples. The modified sensor did not present interferences of K+, Na+, Ca2+, Mg2+, glyphosate, imidacloprid, and carbendazim. In addition, the device showed good recovery values for thiamethoxam when applied directly to honey and water samples without any treatment, presenting an electrochemical sensor to monitor real-time hazardous substances in environmental and food matrices.


Subject(s)
Honey , Oxides , Electrochemical Techniques/methods , Electrodes , Limit of Detection , Oxides/chemistry , Silicon Dioxide , Soot , Thiamethoxam , Titanium , Water
15.
Talanta ; 250: 123718, 2022 Dec 01.
Article in English | MEDLINE | ID: mdl-35797860

ABSTRACT

Antifouling paints containing Cu, Zn, organotins, and many organic booster biocides may be found in ships and watercraft hulls to avoid the fouling of marine organisms. This type of paint can be harmful to the environment, therefore, the monitoring of toxic elements and compounds in antifouling paints are of great importance to access its quality and potential toxicity to the environment. Hence, this work describes the development of microwave-assisted digestion methods for the determination of Cu and Sn in antifouling paints by inductively coupled plasma optical emission spectrometry (ICP OES). The factors: sample mass and solutions of HNO3, HF, and HCl were optimized using the central composite design (CCD). Dry ashing with a muffle furnace and laser ablation-ICP-MS were used for methodological comparison with the microwave digestion-assisted ICP-OES methods. All the mixtures of acids allowed efficient extraction of the analytes; however, the one that stood out was the use of HF, HNO3, and H2O2.


Subject(s)
Biofouling , Disinfectants , Biofouling/prevention & control , Digestion , Hydrogen Peroxide , Microwaves , Paint , Spectrum Analysis
16.
Environ Monit Assess ; 193(12): 767, 2021 Nov 03.
Article in English | MEDLINE | ID: mdl-34731306

ABSTRACT

The sediment contamination by trace metals in coastal aquatic ecosystems is a worldwide environmental problem, since metals can be toxic, persistent, and bioaccumulated. In case of natural events, such as storms, or anthropogenic activities, like dredging, the sediment resuspension to the water column occurs and can solubilize metals, probably increasing their bioavailability and consequently the risk to aquatic life. This study evaluated the bioavailability on reactive trace metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in estuarine sediments from Iguaçu and Meriti Rivers, both in the drainage basin of Guanabara Bay (Rio de Janeiro, Brazil). Additionally, a discussion about the anthropogenic interference throughout time of six short sediments cores, calculating three different indexes (contamination factors, CF; potential ecological risk index for a single heavy metal, Eif for short; potential ecological risk, PERI) was performed. It was considered as reactive phase, the metal concentrations obtained using a weak acid extraction (in HCl 1 mol L-1 solution). Zn presented high concentrations after resuspension, being above effect range medium (ERM) (52.81 to 1337.4 mg kg-1). The CF indicated very high contamination degree for Cu (14.62 to 17.96) and Zn (27.80 to 35.85) for both rivers. The Eif for short presented higher risk to Cu and Zn for Iguaçu and Meriti rivers. PERI index classified Meriti River samples as severely contaminated (238.10 to 351.62).


Subject(s)
Metals, Heavy , Water Pollutants, Chemical , Brazil , China , Ecosystem , Environmental Monitoring , Estuaries , Geologic Sediments , Metals, Heavy/analysis , Risk Assessment , Rivers , Water Pollutants, Chemical/analysis
17.
Environ Pollut ; 274: 115889, 2021 Apr 01.
Article in English | MEDLINE | ID: mdl-33223335

ABSTRACT

Exposure to heavy metals, such as lead, is a global public health problem. Lead has a long historic relation to several adverse health conditions and was recently classified as an endocrine disruptor. The aim of this study was to investigate the effects of subacute exposure to lead on the thyroid gland function. Adult male and female Wistar rats received a lead acetate solution containing 10 or 25 mg/kg, by gavage, three times a week, for 14 days. One week later, behavioral testing showed no alterations in anxiety and motor-exploratory parameters, as evaluated by Open-Field and Plus-Maze Tests, but impairment in learning and memory was found in the male 25 mg/kg lead-treated group and in both female lead-treated groups, as evaluated by the Inhibitory Avoidance Test. After one week, serum levels of tT3 were reduced in the 25 mg/kg female group and in the 10 mg∕ kg male group. However, tT4 levels were increased in the 25 mg/kg male group and in both female treated groups. TSH levels did not change and lead serum levels were undetectable. Morphologic alterations were observed in the thyroid gland, including abnormal thyroid parenchyma follicles of different sizes, epithelial stratification and vacuolization of follicular cells, decrease in colloid eosinophilia and vascular congestion, accompanied by morphometric alterations. An increase in collagen deposition was also observed. No differences were observed in TPO activity or protein expression, H2O2 generation by NADPH oxidases or hepatic D1 mRNA expression. However, thyroid NIS protein expression was considerably decreased in the male and female lead-treated groups, while TSHr expression was decreased in the 25 mg/kg female lead-treated group. These findings demonstrated that subacute exposure to lead acetate disrupts thyroid gland function in both sexes, leading to morphophysiological impairment and to changes in learning and memory abilities.


Subject(s)
Lead , Thyroid Gland , Animals , Female , Hydrogen Peroxide , Lead/toxicity , Liver , Male , Rats , Rats, Wistar
18.
Food Chem ; 326: 126978, 2020 Oct 01.
Article in English | MEDLINE | ID: mdl-32413760

ABSTRACT

The aim of this research was to quantify essential trace elements (iron, copper, zinc and iodine) and establish their speciation in human milk. Both the element and the species are important in new-born nutrition. Colostrum, and transitional and mature milks (25) were collected from 18 mothers of pre-term or full-term infants. Concentrations of the target elements were determined using ICP-MS. For speciation, HPLC coupled to ICP-MS was employed. Total contents of the micronutrients varied in mothers of pre-term (Fe = 0.997, Cu = 0.506, Zn = 4.15 and I = 0.458 mg L-1) and mothers of full-term (Fe = 0.733, Cu = 0.234, Zn = 2.91 and I = 0.255 mg L-1) infants. Fe, Cu and Zn were associated with biomolecules with high molecular mass compounds, such as immunoglobulins, albumin and lactoferrin whilst iodine was only found as iodide.


Subject(s)
Copper/analysis , Iodine/analysis , Iron/analysis , Mass Spectrometry/methods , Milk, Human/chemistry , Zinc/analysis , Adult , Chromatography, High Pressure Liquid , Female , Humans , Iodine/isolation & purification , Iron/isolation & purification , Pregnancy , Zinc/isolation & purification
19.
Eng. sanit. ambient ; Eng. sanit. ambient;23(5): 995-1000, set.-out. 2018. tab
Article in Portuguese | LILACS | ID: biblio-975144

ABSTRACT

RESUMO Áreas contaminadas por metais podem configurar sério risco à saúde pública e ao meio ambiente. Na década de 1980 foi instalado um pátio de estocagem provisória de resíduos industriais perigosos (CENTRES), no município de Queimados, Rio de Janeiro, o que causou um grande impacto ambiental ao solo da região. A legislação brasileira para o diagnóstico de áreas contaminadas limita a extração de metais em solos aos métodos recomendados pela United States Environmental Protection Agency (USEPA) 3050 e 3051A. Entretanto, muitos pesquisadores utilizam o método com água-régia para a extração de metais em solo, mas são escassos estudos que comparem as concentrações de metais extraídos por água-régia e USEPA 3051A. Logo, o objetivo deste trabalho foi avaliar se o método de extração de metais em solos por água-régia é estatisticamente diferente do método USEPA 3051A. Os resultados obtidos revelaram que as concentrações de Cd, Cr, Cu, Ni, Pb e Zn utilizando ambas as extrações (água-régia e USEPA 3051A) foram estatisticamente semelhantes. Também foi possível identificar que as concentrações de Cu, Ni, Pb e Zn foram superiores ao valor de investigação industrial, o que caracteriza essa área como altamente contaminada e solo classe 4.


ABSTRACT Metal contaminated areas lead to environmental and public health risks. In the 1980s, dangerous industrial waste storage was initiated in the CENTRES area in the municipality of Queimados, Rio de Janeiro, Brazil. The inadequate management of these wastes has promoted a large environmental impact to this region's soils. The Brazilian legislation for diagnostics of contaminated areas limits the extraction of metals on soils to USEPA 3050-B and USEPA 3051-A methods. However, many researchers use the aqua regia method for extracting metals in soil, but there are few studies comparing concentrations of metals extracted by aqua regia and USEPA 3051A. Therefore, the objective of this work was to evaluate if the method of extracting metals in soils by aqua regia is statistically different from US EPA 3051A. The results showed that the Cd, Cr, Cu, Ni, Pb and Zn concentrations using both extractions were statistically similar. It was also observed that Cu, Ni, Pb and Zn concentrations were higher than the industrial investigation value which characterizes this area as highly contaminated and soil class 4.

20.
Sci Rep ; 8(1): 11963, 2018 08 10.
Article in English | MEDLINE | ID: mdl-30097589

ABSTRACT

Bone mineral density is an important parameter for the diagnosis of bone diseases, as well as for predicting fractures and treatment monitoring. Thus, the aim of the present study was to evaluate the potential of Quantitative Ultrasound (QUS) to monitor bone changes after calcium, phosphorus, and magnesium loss in rat femurs in vitro during a demineralization process. Four quantitative ultrasound parameters were estimated from bone surface echoes in eight femur diaphysis of rats. The echo signals were acquired during a decalcification process by Ethylenediaminetetraacetic Acid (EDTA). The results were compared to Quantitative Computed Tomography (QCT) and inductively coupled plasma optical emission spectrometry measurements for validation. Integrated Reflection Coefficient (IRC) reflection parameters and Frequency Slope of Reflection Transfer Function (FSRTF) during demineralization tended to decrease, while the backscattering parameter Apparent Integrated Backscatter (AIB) increased and Frequency Slope of Apparent Backscatter (FSAB) showed an oscillatory behavior with no defined trend. Results indicate a clear relation between demineralization and the corresponding decrease in the reflection parameters and increase in the scattering parameters. The trend analysis of the fall curve of the chemical elements showed a better relationship between IRC and QCT. It was possible to monitor bone changes after ions losses, through the QUS. Thus, it is an indication that the proposed protocol has potential to characterize bone tissue in animal models, providing consistent results towards standardization of bone characterization studies by QUS endorsing its use in humans.


Subject(s)
Bone and Bones/diagnostic imaging , Bone and Bones/metabolism , Calcium/metabolism , Femur , Magnesium/metabolism , Phosphorus/metabolism , Ultrasonography , Animals , Bone Density , Rats , Ultrasonography/methods
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