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1.
J Trace Elem Med Biol ; 65: 126717, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33647737

RESUMO

BACKGROUND: Seafood present important advantages for human nutrition, but it can also accumulate high levels of toxic and potentially toxic elements. Culinary treatments could influence seafood chemical element content and element bioavailability. In this study, the influence of culinary treatments on the total concentration and on the bioavailability of Cd, Cr, Cu and Pb in shark, shrimp, squid, oyster, and scallop was assessed. METHODS: Boiling, frying, and sautéing with or without seasonings (salt, lemon juice and garlic) were evaluated. Total concentration and bioavailability of Cd, Cr, Cu and Pb in seafood after all these culinary treatments were compared with those in uncooked samples. Analytes were determined by triple-quadrupole inductively coupled plasma mass spectrometry (ICP-MS/MS). An alternative to express the results avoiding underestimated or overestimated values was proposed. RESULTS: The analytes concentration in seafood without culinary treatment varied from 0.0030 µg g-1 (shrimp) to 0.338 µg g-1 (oyster) for Cd; 0.010 µg g-1 (squid) to 0.036 µg g-1 (oyster) for Cr; 0.088 µg g-1 (scallop) to 8.63 µg g-1 (oyster) for Cu, and < 0.005 µg g-1 (shrimp, squid and oyster) to 0.020 µg g-1 (shark) for Pb. Only Cd (in scallop) was influenced by culinary treatments (reduction from 37 to 53 % after boiling, frying, and sautéing). Bioavailability percentage varied from 11% (oyster) for Cd; 18% (oyster) to 41% (shark) for Cr; 6% (shark) for Cu, and 8% (oyster) for Pb. Bioavailability percentage was not influenced by culinary treatments. CONCLUSION: Cadmium concentration was reduced in scallop after some culinary treatments (reduction o 37-53% after boiling, frying, and sautéing), but bioavailability percentage was not influenced. The employed analytical method was adequate for the purpose, presenting import results for food safety assessment about the influence of culinary treatments on metals concentration and bioavailability in seafood.


Assuntos
Cádmio/análise , Cromo/análise , Culinária , Cobre/análise , Chumbo/análise , Alimentos Marinhos/análise , Disponibilidade Biológica , Cádmio/farmacocinética , Cromo/farmacocinética , Cobre/farmacocinética , Contaminação de Alimentos/análise , Humanos , Chumbo/farmacocinética
2.
Environ Geochem Health ; 43(4): 1441-1456, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31599372

RESUMO

Biochar (BC) is a porous, carbonaceous material produced by slow pyrolysis of biomass under oxygen-limited conditions. BC production has been attracting research interest because it modifies soil physicochemical characteristics and improves the growth of plants in problem soils. These benefits may be best actualized for soils contaminated by metals, where remediation is hampered by metal toxicity to both plants and soil microbial communities. The objectives of this study were to evaluate the impact of the addition of chicken manure biochar (CMB), oat hull biochar (OHB), or pine bark biochar (PBB) on copper (Cu) bioavailability in a Cu-contaminated soil, the effectiveness of these BCs promoting plant growth, and its effects on soil microbial communities supporting these plants. A sandy soil (338 mg Cu kg-1) was amended with CMB, OHB, and PBB, and the metallophyte Oenothera picensis or the agricultural species Solanum lycopersicum and Lolium perenne were grown for 3 months. The BCs produced an increase in soil pH, reduced the exchangeable Cu, and increased Cu bound to organic matter and residual fractions. All BCs enhanced the quality of contaminated soil and increased the plant biomass production, notably for S. lycopersicum, which grew until 12 times more than plants in non-amended soil. While BC addition reduced the concentration of Cu in soil pore water, the amendment did not reduce the concentrations of Cu in shoot tissues. BC additions also stimulated soil microorganisms, increasing basal respiration and DHA activity and modifying microbial communities, especially in soils supporting L. perenne. These results indicate that BCs represent an effective tool to remediate Cu-contaminated sandy soils.


Assuntos
Carvão Vegetal , Cobre/química , Produtos Agrícolas , Microbiologia do Solo , Poluentes do Solo/química , Animais , Disponibilidade Biológica , Biomassa , Galinhas , Chile , Cobre/análise , Cobre/farmacocinética , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/metabolismo , Concentração de Íons de Hidrogênio , Lolium/efeitos dos fármacos , Lolium/metabolismo , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/metabolismo , Esterco , Oenothera/efeitos dos fármacos , Oenothera/metabolismo , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/farmacocinética
3.
Chemosphere ; 239: 124767, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31518925

RESUMO

The present study analyzed the Peruvian scallop Argopecten purpuratus and its food sources for metal and fatty acid concentrations in order to determine spatial and temporal differences. Metals such as copper (Cu), manganese (Mn), and zinc (Zn) in gills and iron (Fe) and Zn in sediments were the most significant explaining factors for spatial differentiations (degree of contamination), while for fatty acids, it was C14:0, C15:0, C16:0 and C18:0 in A. purpuratus' muscle and in its food sources, which explained more temporal differences (El Niño-Southern Oscillation (ENSO) effect). Gills, digestive gland and intestine were the tissues where metal accumulation was the highest in A. purpuratus. Cd in digestive gland was always high, up to ∼250-fold higher than in other tissues, as previously reported in other bioindicator species for metal pollution. Fatty acids were good biomarkers when annual comparisons were performed, while metals when locations were compared. ENSO 2017 played an important role to disentangle A. purpuratus' biological conditions and food sources. A. purpuratus from Paracas locations mostly showed higher metal concentrations in gills and digestive glands, and lower fatty acid concentrations in muscle than those from Sechura and Illescas Reserved Zone.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Pectinidae/química , Poluentes Químicos da Água/análise , Animais , Aquicultura , Cobre/análise , Cobre/farmacocinética , Biomarcadores Ambientais , Ácidos Graxos/análise , Brânquias/química , Ferro/análise , Ferro/farmacocinética , Manganês/análise , Manganês/farmacocinética , Músculos/química , Pectinidae/metabolismo , Peru , Frutos do Mar/análise , Análise Espaço-Temporal , Distribuição Tecidual , Zinco/análise , Zinco/farmacocinética
4.
Environ Geochem Health ; 42(2): 601-615, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31428946

RESUMO

The Caco-2 cell line is derived from a human colon adenocarcinoma and is generally used in toxicity assays. The ingestion of soil or dust is a significant route of human exposure to potential harmful elements (PHE), and assays of bioaccessibility or bioavailability can be used to measure the potential hazard posed by exposure to toxic substances. The in vitro digestion (UBM method) and Caco-2 cell model were used to investigate the bioaccessibility and absorption by intestinal cells of the PHE in four matrices (two urban soils and two soils with lead (Pb)-mining tailings) along with the guidance material for bioaccessibility measurements, BGS 102. The gastrointestinal (GI) compartment was simulated, and the resulting material added to Caco-2 cells. In the GI, the average bioaccessibility was 24% for cadmium (Cd), 17% for copper (Cu), 0.2% for Pb, 44% for manganese (Mn) and 6% for zinc (Zn). The poor reproducibility was attributed to the pH (6.3) and the highly complex GI fluid that formed PHE precipitates and complexes. In 2 h, Caco-2 cells absorbed 0.2 ng mg-1 of cellular protein for Cd, 13.4 ng mg-1 for Cu, 5 ng mg-1 for Mn and 31.7 µg mg-1 for Zn. Lead absorption was lower than the limit of quantification (< 2 µg L-1). Cd was presented in the cell monolayer and could interfere in the intracellular accumulation of Cu, Mn and Zn. The use of in vitro assays allowed for an estimation of the absorption of Cd, Cu, Mn and Zn from environmental matrices to be made, and except for Mn, it had a positive correlation with bioaccessible concentration, suggesting a common association of these elements in the cellular environment.


Assuntos
Cádmio/farmacocinética , Cobre/farmacocinética , Poluentes Ambientais/farmacocinética , Manganês/farmacocinética , Zinco/farmacocinética , Disponibilidade Biológica , Brasil , Células CACO-2 , Cidades , Digestão , Poeira , Humanos , Concentração de Íons de Hidrogênio , Mineração , Reprodutibilidade dos Testes , Solo/química , Poluentes do Solo/farmacocinética , Testes de Toxicidade
5.
Environ Geochem Health ; 41(2): 603-615, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30022342

RESUMO

This study aimed to evaluate mine water reuse, elucidating the potential problems related to trace metal biogeochemistry focusing on Cu dynamics in water, soil, and plants. Water samples were collected from a Cu mine and a reservoir used to store mine water. Additional samples were taken from soils from an uncultivated area and a banana orchard (irrigated with mine water for at least 10 years) and plant from the irrigated area. The following parameters were analyzed: pH, redox potential, dissolved ions in water samples (e.g., Ca2+, Mg2+, Na+, K+, Cu2+, SO 4 2- , and Cl-), bioavailable Cu and Cu solid-phase fractionation (in soils and reservoir sediments samples), as well as Cu content in banana plants. Mine water presents high dissolved Cu concentration (mean 2.3 ± 0.0 mg L-1), limiting its use for irrigation. Water storage at the reservoir increased water quality, reducing dissolved Cu concentration (mean 0.2 ± 0.0 mg L-1), due to adsorption/precipitation as carbonates (mean 131.8 ± 24.6 mg kg-1), organic matter (mean 1526.2 ± 4.7 mg kg-1) and sulfides (mean 158.4 ± 56.9 mg kg-1). Despite higher water quality at the reservoir, the use of mine water increased the amount of bioavailable Cu in soils, which was primarily associated with organic matter. Increased bioavailable Cu in the soil did not increase the Cu content of banana leaves but resulted in high Cu content of roots and fruit, increasing the risk of toxicity for the population.


Assuntos
Irrigação Agrícola/métodos , Cobre/análise , Cobre/farmacocinética , Mineração , Musa/química , Disponibilidade Biológica , Brasil , Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Sedimentos Geológicos/química , Metais/análise , Musa/efeitos dos fármacos , Musa/metabolismo , Medição de Risco/métodos , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/farmacocinética , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/farmacocinética , Qualidade da Água
6.
Sci Total Environ ; 595: 920-927, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28432992

RESUMO

Metal bioaccumulation and toxicity to aquatic organisms depends on factors such as magnitude, duration and frequency of the exposure. The type of the exposure affects the toxicokinetic processes in the organisms. In this study, we carried out 30-day toxicity tests on juveniles of Ruditapes philippinarum exposed to increasing, continuous and pulsed exposure. Organisms were exposed to copper-spiked sediments followed by a 10-day recovery period. We assessed the interaction between the kinetics of subcellular copper partitioning and the growth response. Results showed that the growth rate of the bivalve was inversely correlated to the bioaccumulation rate and that sublethal copper concentrations stimulated the detoxification mechanisms inside the organism regardless the type of the exposure. However, a large stimulatory effect on growth was observed during the recovery period, associated with significant negative accumulation rate values and dependent on the type of antecedent exposure. This suggested that on individual and short-term basis pulsed exposures have a more adverse effect compared to increasing or continuous exposure scenarios.


Assuntos
Bivalves/metabolismo , Cobre/farmacocinética , Sedimentos Geológicos/química , Poluentes Químicos da Água/farmacocinética , Animais , Cinética
7.
Appl Radiat Isot ; 115: 18-22, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27295514

RESUMO

The aim of this study was to obtain data on the biodistribution of (64)CuCl2 in rats and to obtain estimates of the radiation doses to humans by extrapolating the animal data. MicroPET imaging and biodistribution studies were carried out with Wistar rats, and the doses were estimated with OLINDA/EXM. The lower large intestine wall was found to be the critical organ with an absorbed dose of 139±34 and 125±32µGy/MBq for females and males, respectively. The corresponding effective doses were estimated as 47±4 and 39±4µSv/MBq.


Assuntos
Cobre/farmacocinética , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/farmacocinética , Animais , Feminino , Humanos , Masculino , Radiometria , Ratos , Ratos Wistar , Nanomedicina Teranóstica , Distribuição Tecidual
8.
J R Soc Interface ; 12(110): 0509, 2015 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-26269233

RESUMO

This work aimed to develop novel composite biomaterials for bone tissue engineering (BTE) made of bioactive glass nanoparticles (Nbg) and alginate cross-linked with Cu(2+) or Ca(2+) (AlgNbgCu, AlgNbgCa, respectively). Two-dimensional scaffolds were prepared and the nanocomposite biomaterials were characterized in terms of morphology, mechanical strength, bioactivity, biodegradability, swelling capacity, release profile of the cross-linking cations and angiogenic properties. It was found that both Cu(2+) and Ca(2+) are released in a controlled and sustained manner with no burst release observed. Finally, in vitro results indicated that the bioactive ions released from both nanocomposite biomaterials were able to stimulate the differentiation of rat bone marrow-derived mesenchymal stem cells towards the osteogenic lineage. In addition, the typical endothelial cell property of forming tubes in Matrigel was observed for human umbilical vein endothelial cells when in contact with the novel biomaterials, particularly AlgNbgCu, which indicates their angiogenic properties. Hence, novel nanocomposite biomaterials made of Nbg and alginate cross-linked with Cu(2+) or Ca(2+) were developed with potential applications for preparation of multifunctional scaffolds for BTE.


Assuntos
Cálcio , Cobre , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células-Tronco Mesenquimais/metabolismo , Nanocompostos/química , Engenharia Tecidual , Alicerces Teciduais/química , Animais , Substitutos Ósseos/química , Substitutos Ósseos/farmacocinética , Cálcio/química , Cálcio/farmacocinética , Cobre/química , Cobre/farmacocinética , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/citologia , Ratos , Ratos Sprague-Dawley
9.
J Agric Food Chem ; 63(28): 6331-7, 2015 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-26134249

RESUMO

In vitro gastrointestinal digestion of babassu mesocarp in the absence and presence of milk and lignin was performed to evaluate the bioaccessibility of Cu, Fe, and Zn. Extractions using NaOH solutions (pH 7 and 12) were carried out to evaluate the interactions of Cu(II), Fe(III), and Zn(II) with the extracted compounds and with the washed mesocarp. Studies using reference solutions showed a decrease in the free concentration of the elements in the presence of mesocarp. Phytate, a component present in the mesocarp, can be the main compound responsible for the elements' interactions with mesocarp. Lignin increases the elements' soluble fractions; however, the elements' concentrations in the dialyzed fractions, representing the bioaccessible portion, were very low. On the other hand, Cu, Fe, and Zn bioaccessibility in milk was not influenced by the mesocarp.


Assuntos
Arecaceae/metabolismo , Cobre/farmacocinética , Digestão , Ferro/farmacocinética , Sementes/metabolismo , Zinco/farmacocinética , Animais , Arecaceae/química , Disponibilidade Biológica , Cobre/análise , Humanos , Ferro/análise , Lignanas/farmacologia , Leite/química , Sementes/química , Zinco/análise
10.
Artigo em Inglês | MEDLINE | ID: mdl-23403295

RESUMO

We studied the recovery of juvenile fat snook (Centropomus parallelus) after subchronic exposure to different concentrations of copper. Healthy juveniles (1.98 g) were exposed to 25 or 50 µg Cu/L for 30 days (12 replicates with 5 fish in each one), and recovery was observed at 0, 4, 10, and 30 days after exposure (3 replicates with 5 fish in each one). Copper genotoxicity in exposed individuals was observed using a micronucleus assay, and recovery was not observed even 30 days post-exposure. Copper accumulation was observed in fish exposed to 25 or 50 µg/L of copper in the gills (14.4 and 34.4 µg/g, respectively) and muscle (5.7 and 5.5 µg/g, respectively), and a return to normal copper levels (6.0 µg/g for gills and 2.5 µg/g for muscle) was observed 4 and 30 days post-exposure in the gills and muscle tissues, respectively. Glutathione S-transferase (GST) was 80% inhibited in individuals exposed to copper and returned to normal levels for fish exposed to basal concentrations within 10 days. Although copper accumulation in tissues dispersed 30 days post-exposure, no recovery from genotoxicity was observed during this time. Thirty days was not enough to recover juvenile fat snook following subchronic exposure to copper.


Assuntos
Cobre/toxicidade , Perciformes/fisiologia , Poluentes Químicos da Água/toxicidade , Fatores Etários , Animais , Cobre/farmacocinética , Relação Dose-Resposta a Droga , Brânquias/efeitos dos fármacos , Glutationa Transferase/metabolismo , Testes para Micronúcleos , Músculos/efeitos dos fármacos , Distribuição Tecidual , Testes de Toxicidade Subcrônica , Poluentes Químicos da Água/farmacocinética
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