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1.
J Sci Food Agric ; 104(10): 5964-5972, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38437521

RESUMO

BACKGROUND: Seafood consumers are widely exposed to diclofenac due to the high contamination levels often present in aquatic organisms. It is a potential risk to public health due its endocrine disruptor properties. Limited information is available about diclofenac behavior after food digestion to enable a more realistic scenario of consumer exposure. This study aimed to evaluate cooking effects on diclofenac levels, and determine diclofenac bioaccessibility by an in vitro digestion assay, using commercial fish species (seabass and white mullet) as models. The production of the main metabolite 4'-hydroxydiclofenac was also investigated. Fish hamburgers were spiked at two levels (150 and 1000 ng g-1) and submitted to three culinary treatments (roasting, steaming and grilling). RESULTS: The loss of water seems to increase the diclofenac levels after cooking, except in seabass with higher levels. The high bioaccessibility of diclofenac (59.1-98.3%) observed in both fish species indicates that consumers' intestines are more susceptible to absorption, which can be worrisome depending on the level of contamination. Contamination levels did not affect the diclofenac bioaccessibility in both species. Seabass, the fattest species, exhibited a higher bioaccessibility of diclofenac compared to white mullet. Overall, cooking decreased diclofenac bioaccessibility by up to 40% in seabass and 25% in white mullet. The main metabolite 4'-hydroxydiclofenac was not detected after cooking or digestion. CONCLUSION: Thus, consumption of cooked fish, preferentially grilled seabass and steamed or baked white mullet are more advisable. This study highlights the importance to consider bioaccessibility and cooking in hazard characterization studies. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Culinária , Diclofenaco , Digestão , Contaminação de Alimentos , Alimentos Marinhos , Diclofenaco/metabolismo , Diclofenaco/química , Animais , Contaminação de Alimentos/análise , Alimentos Marinhos/análise , Peixes/metabolismo , Bass/metabolismo , Humanos , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/química , Smegmamorpha/metabolismo , Modelos Biológicos
2.
Sensors (Basel) ; 23(10)2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37430513

RESUMO

Nowadays, optical systems play an important role in communications. Dual depletion PIN photodiodes are common devices that can operate in different optical bands, depending on the chosen semiconductors. However, since semiconductor properties vary with the surrounding conditions, some optical devices/systems can act as sensors. In this research work, a numerical model is implemented to analyze the frequency response of this kind of structure. It considers both transit time and capacitive effects, and can be applied to compute photodiode frequency response under nonuniform illumination. The InP-In0.53Ga0.47As photodiode is usually used to convert optical into electrical power at wavelengths around 1300 nm (O-band). This model is implemented considering an input frequency variation of up to 100 GHz. The focus of this research work was essentially the determination of the device's bandwidth from the computed spectra. This was performed at three different temperatures: 275 K, 300 K, and 325 K. The aim of this research work was to analyze if a InP-In0.53Ga0.47As photodiode can act as a temperature sensor, to detect temperature variations. Furthermore, the device dimensions were optimized, to obtain a temperature sensor. The optimized device, for a 6 V applied voltage and an active area of 500 µm2, had a total length of 2.536 µm, in which 53.95% corresponded to the absorption region. In these conditions, if the temperature increases 25 K from the room temperature, one should expect a bandwidth increase of 8.374 GHz, and if it decreases 25 K from that reference, the bandwidth should reduce by 3.620 GHz. This temperature sensor could be incorporated in common InP photonic integrated circuits, which are commonly used in telecommunications.

3.
Environ Res ; 210: 112886, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35150711

RESUMO

Currently, the presence of endocrine disrupting chemicals (EDCs) in the marine environment pose а potential risk to both wildlife and human health. The occurrence of EDCs in seafood depends of several factors such as source and amounts of EDCs that reach the aquatic environment, physicochemical features of EDCs, and its accumulation in trophic chain. This review highlights the occurrence and distribution of EDCs along the seafood in the last 6 years. The following EDCs were included in this review: brominated flame retardants (PBDEs, PBBs, HBCDDs, TBBPA, and novel flame retardants); pharmaceuticals (paracetamol, ibuprofen, diclofenac, carbamazepine), bisphenols, hormones, personal care products (Musk and UV Filters), and pesticides (organochlorides, organophosphates, and pyrethroids). Some of them were found above the threshold that may cause negative effects on human, animal, and environmental health. More control in some countries, as well as new legislation and inspection over the purchase, sale, use, and production of these compounds, are urgently needed. This review provides data to support risk assessment and raises critical gaps to stimulate and improve future research.


Assuntos
Disruptores Endócrinos , Retardadores de Chama , Animais , Disruptores Endócrinos/análise , Éteres Difenil Halogenados/análise , Organofosfatos , Alimentos Marinhos/análise
4.
Environ Res ; 214(Pt 4): 114157, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36027956

RESUMO

In this study, we investigated factors that influence the differences in exposure of perfluoroalkyl acids (PFAAs) from eight species of Antarctic seabirds, including Pygoscelis penguins, Stercorarius maccormicki, and Macronectes giganteus. We analyzed the relationship between foraging ecology (based on δ13C, δ15N, and δ34S values) and PFAAs accumulated in eggs and breast feathers. Ten out of 15 targeted PFAAs were detected in eggs compared to eight in feathers. Mean ∑PFAA concentrations in feathers ranged from 0.47 in P. antarcticus to 17.4 ng/g dry weight (dw) in S. maccormicki. In eggs, ∑PFAA concentrations ranged from 3.51 in P. adeliae to 117 ng/g dw in S. maccormicki. The highest concentrations of most PFAAs were found in trans-equatorial migrators such as S. maccormicki, probably due their high trophic position and higher concentrations of PFAAs in the Northern Hemisphere compared to the Southern Hemisphere. Based on stable isotopes correlations, our results suggest that the trophic position (δ15N) and the foraging area (δ13C and δ34S) influence PFAAs concentrations in Antarctic seabirds. Our results point to the possibility that long-distance migratory birds may have as bio-vectors in the transport of pollutants, including PFCAs, in Antarctic environments, although this must be further confirmed in future studies using a mass balanced approach, such as extractable organofluorine (EOF).


Assuntos
Poluentes Ambientais , Fluorocarbonos , Spheniscidae , Animais , Regiões Antárticas , Monitoramento Ambiental/métodos , Plumas/química , Fluorocarbonos/análise
5.
An Acad Bras Cienc ; 94(suppl 2): e20211215, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35730899

RESUMO

Oil spills, intrinsically related to the petroleum production chain, represent a risk to the marine environment and a potential threat to humans through seafood consumption. We revised the NE Brazil oil spill and other accidents along the Brazilian coast, with a focus on seafood contamination, covering topics such as bioaccumulation, bioaccessibility, and risk analysis. Comprehensive knowledge of the impacts of spills helps in the interpretation of the dynamics of hydrocarbons released into the sea, contributing to actions to control their negative impacts. Currently, no legal limits have been established permanently in Brazil for PAHs in seafood edible tissues.


Assuntos
Poluição por Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Acidentes , Organismos Aquáticos , Monitoramento Ambiental , Humanos , Poluição por Petróleo/efeitos adversos , Poluição por Petróleo/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Medição de Risco , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
6.
J Environ Sci Health B ; 55(12): 1087-1098, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32900284

RESUMO

Poultry litter soil application contributes to sustainability of agricultural systems and is in accordance with the United Nations Sustainable Development Goals (UN-SDG). Poultry litter recommended rates are based on crop nitrogen (N) needs, however, their application can be a potential source of antibiotics and trace elements overload. The aim of the study was to estimate the role of poultry litter application on soil contamination by fluoroquinolones [enrofloxacin (ENR) and ciprofloxacin (CIP)] and trace elements, based on N requirements for crops. Analytical and sampling techniques were used to estimate the loads from poultry litter application. Only CIP was found in poultry litter samples (283 ± 124 µg kg-1) and its load was estimated to be of 9.89 ± 4.33 g ha-1, for the poultry litter application (35 t ha-1). The estimated loads (g ha-1) of trace elements were: Cr 9.19 ± 3.26, Ni 12.3 ± 4.93, Pb 22.0 ± 8.26, Cu 229 ± 85.6, Mn 691 ± 259 and Zn 1,011 ± 378. These estimates were 900% higher than those recommended by the technical guidance, while N exceeded 600% the recommended application. In order to achieve UN-SDGs, local policies to disseminate knowledge and technologies are required for consolidating sustainable agricultural practices.


Assuntos
Fluoroquinolonas/análise , Esterco/análise , Nitrogênio , Aves Domésticas , Poluentes do Solo/análise , Oligoelementos/análise , Agricultura , Animais , Brasil , Ciprofloxacina/análise , Produtos Agrícolas , Enrofloxacina/análise , Fertilizantes , Solo/química
7.
J Environ Sci Health B ; 55(1): 30-41, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31496395

RESUMO

Organochlorine (OCP) pesticides were determined in samples of sardine (Sardinella brasiliensis), whitemouth croaker (Micropogonias furnieri), and mullet (Mugil liza) from Guanabara Bay (state of Rio de Janeiro, Brazil). OCP concentrations and fish consumption were linked with acceptable daily intake values in order to assess the human health risk for the Brazilian population. The total concentrations of OCPs (Σ OCP) was 6.6 ng/g f.w., 7.5 ng/g f.w., and 2.8 ng/g f.w. for sardines, corvina, and mullet, respectively. There was a significant difference (P < 0.05) among the species related to o,p'-DDD and o,p'-DDT concentrations. Both DDT-related compounds were 5 and 76 times more abundant in sardines than in whitemouth croaker and mullet. Newly discovered DDT metabolite, o-Cl-DDMU, was frequently detected in the fish. None of the samples exceeded the maximum limits for acceptable levels of OCP residues. According to the data of average intake of Brazilian population, none of three species exceeded toxicological parameter. The investigated fishes are considered as safe for human consumption in regard to exposure of the studied OCPs. However, fish may be a intake source of OCP metabolites such as o-Cl-DDMU whose toxicity is still unknown.


Assuntos
Produtos Pesqueiros/análise , Contaminação de Alimentos/análise , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Poluentes Químicos da Água/análise , Animais , Baías , Brasil , DDT/análise , DDT/metabolismo , Diclorodifenil Dicloroetileno/análise , Diclorodifenil Dicloroetileno/metabolismo , Monitoramento Ambiental , Peixes , Humanos , Nível de Efeito Adverso não Observado , Medição de Risco
8.
Environ Monit Assess ; 191(1): 28, 2018 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-30591972

RESUMO

Poultry litter is widely used as fertilizer in soils and can be a relevant source of heavy metals for agricultural environments. In this study, poultry litter fertilization of long-term (< 1-30 years) was evaluated in tropical soils. Our main goal was to investigate the occurrence of temporal variation in the available fraction of heavy metals (Cu, Cr, Zn, Pb, Cd, and Mn) in soils, in addition to their environmental loads through new indexes for risk assessment. The highest mean concentrations in poultry litter were the following: 525 mg kg-1 for Mn, 146 mg kg-1 for Zn, and 94.4 mg kg-1 for Cu. For soils, concentrations were higher for the same heavy metals: Mn (906 mg kg-1), Zn (111 mg kg-1), and Cu (26.3 mg kg-1). Significant accumulation (p < 0.05) in fertilized soils was observed for Cu, Cr, and Zn. The high estimates of poultry litter input based on geological background (LIGB) for Cu, Cr, and Zn coincided with the accumulation observed in soils, confirming the effectiveness of the index. The risk of biogeochemical transfer based on fertilized soils (LIFS) decreased for Cu, Cr, and Zn between 10 and 30 years of soil fertilization. For Mn, a very high LIFS was estimated in all long-term fertilized soils. The proposed indices, based on heavy metal concentration, can be used in risk assessments to guide future studies that analyze other environmental matrices possibly impacted by manure and poultry litter fertilization.


Assuntos
Monitoramento Ambiental/métodos , Fertilizantes/análise , Esterco/análise , Metais Pesados/análise , Solo/química , Agricultura , Animais , Brasil , Aves Domésticas , Medição de Risco , Poluentes do Solo/análise
9.
Ren Fail ; 35(5): 680-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23650973

RESUMO

Despite the fact that low plasma zinc (Zn) levels play important roles in the oxidative stress, the relationships between lipid peroxidation and inflammation biomarkers with low plasma Zn levels have not been investigated in chronic kidney disease (CKD) patients. The aim of this study was to evaluate the Zn plasma levels, electronegative LDL [LDL(-)] levels, and inflammation markers as predictors of cardiovascular (CV) mortality in hemodialysis (HD) patients. Forty-five HD patients (28 men, 54.2 ± 12.7 years, 62.2 ± 51.4 months on dialysis and BMI 24.3 ± 4.1 kg/m(2)) were studied and compared to 20 healthy individuals (9 men, 51.6 ± 15.6 years, BMI 25.2 ± 3.9 kg/m(2)) and followed for 24 months to investigate the risks for CV mortality. LDL(-) levels were measured by ELISA, plasma Zn levels by atomic absorption spectrophotometry, C-reactive protein (CRP) level by immunoturbidimetric method, and tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), monocyte chemotactic protein-1 (MCP-1), and plasminogen activator inhibitor-1 (PAI-1) levels by a multiplex assay kit. HD patients presented low plasma Zn levels (54.9 ± 16.1 µg/dL) and high-LDL(-) (0.18 ± 0.12 U/L) and TNF-α (5.5 ± 2.2 pg/mL) levels when compared to healthy subjects (78.8 ± 9.4µ g/dL, 0.10 ± 0.08U/L, 2.4 ± 1.1 pg/mL, respectively, p < 0.05). Zn plasma levels were negatively correlated to TNF-α (r = -0.49; p = 0.0001) and LDL(-) (r = -0.33; p = 0.008). During the 2 years, 24.4% of the patients died, all due to CV disease. Analysis by the Cox model showed that high CRP, TNF-α, IL-6 levels, and long duration of HD were significant predictors of mortality. In conclusion, reduced Zn levels were associated with lipid peroxidation and inflammation, and we confirm here in a Brazilian cohort of HD patients that inflammation markers are strong predictors of CV death.


Assuntos
Doenças Cardiovasculares/sangue , Falência Renal Crônica/sangue , Peroxidação de Lipídeos , Lipoproteínas LDL/sangue , Zinco/sangue , Adulto , Idoso , Brasil/epidemiologia , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/mortalidade , Estudos de Casos e Controles , Feminino , Voluntários Saudáveis , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/mortalidade , Masculino , Pessoa de Meia-Idade , Diálise Renal , Fatores de Risco
10.
Micromachines (Basel) ; 14(2)2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36838063

RESUMO

Renewable energy sources are becoming more and more essential to energy production as societies evolve toward a fossil-fuel-free world. Solar energy is one of the most abundant sources of green energy. Nanoantennas can be used to improve and enhance the absorption of light into a photovoltaic cell in order to generate more current. In this study, different nanoantenna structures are analysed in tandem with a silicon solar cell in an effort to improve its output. The nanoantennas studied are metallic aperture nanoantennas made up of either silver, aluminium, gold or copper. The three geometries compared are rectangular, circular and triangular. The maximum field enhancement obtained is for an aluminium rectangular nanoantenna of 50 nm thickness. Despite this, the geometry with more improvements compared with a basic silicon cell was the circle geometry with a 100 nm radius.

11.
Sci Rep ; 13(1): 12490, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37528136

RESUMO

Renewable energies are increasingly playing an important role in the world's energy supply. Society demands new solutions to solve environmental issues caused by fossil fuels. The importance of photovoltaic technology has been increasing and consequently, the necessity to have more accurate models to characterise the performance of solar cells during their entire lifetime has rose as well. Performance problems may appear during devices' lifetimes associated with factors, such as weather conditions or faulty installation. Cracking might occur, leading to abrupt reductions on the produced power, quite difficult and expensive to fix. The I-V curves of a defected or cracked solar cell might not have the shape imposed by the usual models as 1M5P. In this article, cracked c-Si solar cells are modelled using a novel model: d1MxP. This model is based on the discretisation of the diode's response on models as 1M5P. Instead of imposing a shape and compute some parameters to fit it on experimental data, the proposed model connects every two points. The results suggest a better fit using the proposed model in comparison with the 1M5P, not only in the original curves, but also modelling cracked cells. As consequence of a better fitting, the computation of important figures of merit as maximum power point or fill factor, reveals to be more precise. It is concluded that the proposed model might characterise the performance of a solar cell, even cracked, which is a huge advance aiming the possibility of simulating complex problems during the cells' operation lifetime.

12.
Chemosphere ; 328: 138575, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37011823

RESUMO

Chlorinated paraffins (CPs) are synthetic organic compounds of growing environmental and social concern. Short-chain chlorinated paraffins (SCCPs) were listed under the Stockholm Convention on Persistent Organic Pollutants (POPs) in 2017. Further, in 2021, medium-chain chlorinated paraffins (MCCPs) were proposed to be listed as POPs. We investigated SCCP and MCCP amounts and homolog profiles in four wild fish species from Bahía Blanca Estuary, a South Atlantic Ocean coastal habitat in Argentina. SCCPs and MCCPs were detected in 41% and 36% of the samples, respectively. SCCP amounts ranged from <12 to 29 ng g-1 wet weight and <750-5887 ng g-1 lipid weight, whereas MCCP amounts ranged from <7 to 19 ng g-1 wet weight and <440-2848 ng g-1 lipid weight. Amounts were equivalent to those found in fish from the Arctic and Antarctic Oceans and from some North American and Tibetan Plateau lakes. We performed a human health risk assessment and found no direct risks to human health for SCCP or MCCP ingestion, according to present knowledge. Regarding their environmental behavior, no significant differences were observed among SCCP amounts, sampling locations, species, sizes, lipid content, and age of the specimens. However, there were significant differences in MCCP amounts across species, which could be attributed to fish size and feeding habits. Homolog profiles in all fish were dominated by the medium-chlorinated (Cl6 and Cl7) CPs and shorter chain length CPs were the most abundant, with C10Cl6 (12.8%) and C11Cl6 (10.1%) being the predominant SCCPs and C14Cl6 (19.2%) and C14Cl7 (12.4%) the predominant MCCPs. To the best of our knowledge, this is the first study on the presence of CPs in the environment in Argentina and the South Atlantic Ocean. CP occurrence in the environment, particularly in the food chain, promotes the need for further research on their occurrence and behavior, and the impact of CPs in marine ecosystems in Argentina.


Assuntos
Hidrocarbonetos Clorados , Humanos , Animais , Hidrocarbonetos Clorados/análise , Parafina/análise , Ecossistema , Estuários , Argentina , Brasil , Monitoramento Ambiental , Lipídeos , China
13.
Sci Total Environ ; 905: 167704, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37820801

RESUMO

Guiana dolphins, Sotalia guianensis, are vulnerable to extinction along their distribution on the Brazilian coast and assessing chemical pollution is of utmost importance for their conservation. For this study, 51 carcasses of Guiana dolphins were sampled across the Brazilian coast to investigate legacy and emerging brominated flame retardants (BFRs) as well as the naturally-produced MeO-BDEs. PBDEs and MeO-BDEs were detected in all samples analyzed, whereas emerging BFRs were detected in 16 % of the samples, all in Rio de Janeiro state. PBDE concentrations varied between 2.24 and 799 ng.g-1 lipid weight (lw), emerging BFRs between 0.12 and 1.51 ng.g-1 lw and MeO-BDEs between 3.82 and 10,247 ng.g-1 lw. Concentrations of legacy and emerging BFRs and natural compounds varied considerably according to the sampling site and reflected both the local anthropogenic impact of the region and the diversity/mass of biosynthesizers. The PBDE concentrations are lower than what was found for delphinids in the Northern Hemisphere around the same sampling period and most sampling sites presented mean concentrations lower than the limits for endocrine disruption known to date for marine mammals of 460 ng.g-1 lw, except for sampled from Santa Catarina state, in Southern Brazil. Conversely, MeO-BDE concentrations are higher than those of the Northern Hemisphere, particularly close to the Abrolhos Bans and Royal Charlotte formation, that are hotspots for biodiversity. Despite the elevated concentrations reported for this group, there is not much information regarding the effects of such elevated concentrations for these marine mammals. The distinct patterns observed along the Brazilian coast show that organobrominated compounds can be used to identify the ecological segregation of delphinids and that conservation actions should be planned considering the local threats.


Assuntos
Golfinhos , Retardadores de Chama , Animais , Retardadores de Chama/análise , Brasil , Monitoramento Ambiental , Cetáceos , Éteres Difenil Halogenados/análise
14.
Am J Ind Med ; 55(12): 1159-65, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22314773

RESUMO

BACKGROUND: Fish consumption is considered the most important source of contaminant exposure for humans beings, and farmed fish can be exposed to contaminants via feed supply. METHODS: Total mercury concentrations (THg) were determined in the muscle, liver, and feed of farmed Nile tilapia (juveniles and adults) from four different fish farms in Brazil (net cages and intensive tanks systems), by a flow injection mercury system. RESULTS: Mercury concentrations observed in fish muscle were markedly lower (13.5-30.5 µg kg(-1)) than the values recommended by ANVISA/MAPA for edible part of fish (500 µg kg(-1)), and in the liver the concentrations found were higher than in the muscle. CONCLUSIONS: These low levels of THg in farmed tilapia may be due to the low THg concentrations found in the analyzed fish feed, that ranged from 5.2 to 33.2 µg kg(-1), below the limit of 100 µg kg(-1) established by the European Commission.


Assuntos
Ração Animal/análise , Monitoramento Ambiental , Contaminação de Alimentos/análise , Mercúrio/análise , Músculo Esquelético/química , Tilápia , Animais , Animais Domésticos , Fígado/química , Poluentes Químicos da Água
15.
Am J Ind Med ; 55(12): 1166-71, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22495910

RESUMO

BACKGROUND: Climate change is a natural phenomenon that has been intensified due to increased emissions of greenhouse gases (GHG). It has become an indispensable issue in international negotiations related to global sustainability and is deeply related to the overall status of environmental health in our planet. METHODS: We compiled an inventory of GHG emissions that resulted from human activities at the Brazilian Antarctic Scientific Station "Comandante Ferraz" (EACF) and collected emissions data relating to these activities from January to March 2011. The present work aims to identify the sources of GHG emissions, their characteristics, and composition, using as methodology and framework basis the international ISO 14,064:07 and the GHG Protocol. RESULTS: We addressed emissions of CO(2), CH(4), and N(2)O arising from the use of vehicles, diesel-electric generators, boilers, and wastewater treatment for the sewage treatment plant. We identified that the main GHG emissions derived from the activities of power generation using diesel and boilers (more than 80% of the emissions), adding more than 772 t of CO(2) equivalents. CONCLUSIONS: We identified that the diesel generators and boilers are the most important sources of emission by Expedition XXIX (2010-2011). In that CO(2) is principally emitted in relation to electrical energy generation from diesel generators, we emphasize the need for fuel burning reduction through energy consumption reduction.


Assuntos
Dióxido de Carbono/análise , Monitoramento Ambiental/estatística & dados numéricos , Efeito Estufa , Regiões Antárticas , Brasil , Centrais Elétricas
16.
J Ren Nutr ; 22(3): 350-6, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21741859

RESUMO

BACKGROUND: Iron supplementation is a common recommendation to chronic kidney disease patients undergoing hemodialysis (HD). However, iron excess is closely associated with lipid peroxidation and, it is well known that electronegative low-density lipoproteins (LDL[-]) are present at higher plasma concentrations in diseases with high cardiovascular risk such as chronic kidney disease. Thus, the aim of this study was to investigate whether ferritin levels are associated with LDL(-) levels in HD patients. DESIGN: This was a cross-sectional study. SETTING: This study was conducted from a private clinic in Rio de Janeiro, Brazil. PATIENTS: The study included 27 HD patients and 15 healthy subjects. METHODS AND PROCEDURES: Twenty-seven HD patients (14 men, 58.6 ± 10 years, 62.2 ± 51.4 months on dialysis, and body mass index: 24.4 ± 4.2 kg/m(2)) were studied and compared with 15 healthy individuals (6 men, 53.8 ± 15.4 years, body mass index: 24.5 ± 4.3 kg/m(2)). Serum LDL(-) levels were measured using the enzyme-linked immunosorbent assay method; ferritin levels by commercially available kits, and tumor necrosis factor-α, interleukin-6, monocyte chemoattractant protein-1, and plasminogen activator inhibitor-1 were determined with a multiplex assay kit manufactured by R&D Systems. RESULTS: The HD patients presented higher LDL(-) and tumor necrosis factor-α levels (0.15 ± 0.13 U/L and 5.9 ± 2.3 pg/mL, respectively) than healthy subjects (0.07 ± 0.05 U/L and 2.3 ± 1.3 pg/mL, respectively) (P = .0001). The mean ferritin level in HD patients was 1,117.5 ± 610.4 ng/mL, and 90% of patients showed ferritin levels exceeding 500 ng/mL. We found a positive correlation between LDL(-) and ferritin in the patients (r = 0.48; P = .01), and ferritin was a significant contributor to LDL(-) concentrations independent of inflammation. CONCLUSIONS: Excess body iron stores for HD patients was associated with signs of increased oxidative stress, as reflected by increased LDL(-) levels in HD patients.


Assuntos
Ferritinas/sangue , Lipoproteínas LDL/sangue , Diálise Renal , Adulto , Idoso , Brasil , Quimiocina CCL2/sangue , Estudos Transversais , Feminino , Humanos , Interleucina-6/sangue , Ferro da Dieta/administração & dosagem , Ferro da Dieta/sangue , Masculino , Pessoa de Meia-Idade , Avaliação Nutricional , Estresse Oxidativo/efeitos dos fármacos , Projetos Piloto , Inibidor 1 de Ativador de Plasminogênio/sangue , Fator de Necrose Tumoral alfa/sangue
17.
Chemosphere ; 291(Pt 3): 132674, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34736745

RESUMO

PFAS are a group of organic chemicals, which some presents environmental persistence, dispersion and potential toxicity. Some of them have been listed in the Stockholm Convention as persistent organic pollutants (POPs) to have its production and use restricted, namely PFOS, its salts and PFOSF and PFOA, its salts and related substances. As a Party, Brazil has to comply with the Convention provisions regarding the control of POPs. In order to develop listed PFAS inventories in the country, the Convention guidance documents were used. Stakeholders were consulted and trade data was assessed. Complementary, a review on listed PFAS occurrence in Brazil was performed. From over 1000 queries sent, only 3 answers were received. International trade data showed an import of 93.7 tonnes of PFOSF from China and export of sulfluramid-base ant bait to other developing countries. Domestic trade data showed that around 28 t per year of EtFOSA is commercialized in Brazil. The EtFOSA sold internally could lead to emissions of up to 616 t of PFOS. With domestic and foreign trade data it was possible to estimate the production of EtFOSA from 2010 to 2018 to 40 t per year. Only 10 studies reported listed PFAS occurrence in Brazilian environmental matrices. All of them reported ubiquitous occurrence of listed PFAS in the country, being PFOS the predominant in terms of occurrence and concentration. Brazil needs to develop strategies to overcome the low engagement of stakeholders and enforce control over listed PFAS foreign trade.


Assuntos
Ácidos Alcanossulfônicos , Poluentes Ambientais , Fluorocarbonos , Brasil , Comércio , Fluorocarbonos/análise , Internacionalidade , Poluentes Orgânicos Persistentes
18.
Chemosphere ; 287(Pt 3): 132344, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34826954

RESUMO

Chlorinated paraffins (CPs) are chemicals with multipurpose applications. Their global production has increased despite their adverse impacts on the environment and human health. In 2017, short-chain chlorinated paraffins (SCCPs) were listed as persistent organic pollutants (POPs) in the Stockholm Convention. Yet, specific exemptions were granted for their applications despite the recycling prohibition for products containing SCCPs. Therefore, we aimed to produce the first Brazilian inventory of SCCPs following its respective guidance to evaluate the applicability of the SCCP inventory guidance and to provide technical insights regarding SCCPs in the update of the Brazilian National Implementation Plan (NIP). Moreover, we performed a review of SCCP occurrence in Brazil to fulfil data gaps in the inventory development. We identified and consulted nationwide stakeholders and assessed foreign trade data of CPs and products that might contain CPs in relevant amounts. The Brazilian production of CPs was discontinued in 1994. However, CPs are still imported and used in the country. CPs have been mostly applied as plasticizers, flame retardants and lubricants in Brazil. The import of products containing CPs also pose a significant route of CP entrance into Brazil. Thus, the current end-of-life management of CP-containing products is a bottleneck towards the Convention implementation. The guidance application was feasible and useful despite the low engagement of stakeholders. To assess foreign trade of CPs and CP-containing products, we recommend the use of more specific tracking codes. Besides, the review of SCCP occurrence is not a demanded part for an inventory but was a useful complementation.


Assuntos
Hidrocarbonetos Clorados , Parafina , Brasil , China , Monitoramento Ambiental , Humanos , Hidrocarbonetos Clorados/análise , Parafina/análise
19.
Nanomaterials (Basel) ; 12(18)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36144960

RESUMO

Photovoltaic technology is currently at the heart of the energy transition in our pursuit to lean off fossil-fuel-based energy sources. Understanding the workings and trends of the technology is crucial, given the reality. With most conventional PV cells constrained by the Shockley-Queisser limit, new alternatives have been developed to surpass it. One of such variations are heterojunction cells, which, by combining different semiconductor materials, break free from the previous constraint, leveraging the advantages of both compounds. A subset of these cells are multi-junction cells, in their various configurations. These build upon the heterojunction concept, combining several junctions in a cell-a strategy that has placed them as the champions in terms of conversion efficiency. With the aim of modelling a multi-junction cell, several optic and optoelectronic models were developed using a Finite Element Tool. Following this, a study was conducted on the exciting and promising technology that are nanoantenna arrays, with the final goal of integrating both technologies. This research work aims to study the impact of the nanoantennas' inclusion in an absorbing layer. It is concluded that, using nanoantennas, it is possible to concentrate electromagnetic radiation near their interfaces. The field's profiles might be tuned using the nanoantennas' geometrical parameters, which may lead to an increase in the obtained current.

20.
Artigo em Inglês | MEDLINE | ID: mdl-36497865

RESUMO

Accumulation of pesticides has a harmful impact on the environment and human health. The main goal of this work was to develop a method to determine and quantify the residues of thirteen pesticides in edible fish and bivalves such as parati (Mugil curema), seabass (Centropomus ssp.), mullet (Mugil brasiliensis), clams (Anomalocardia brasiliana) and mussel (Mytilus galloprovincialis) collected from Sepetiba Bay and Parnaiba River Delta (Brazil) between 2019 and 2020. Matrix solid-phase dispersion (MSPD) was used for extraction and quantification through gas chromatography coupled to tandem mass spectrometry (GC-MS/MS). The method was validated (linearity, accuracy and precision) for fatty fish (Salmo salar), lean fish (Mugil curema) and bivalves (Mytilus edulis). The survey found linear correlation coefficients (r) equal to or greater than 0.9 for almost all analytes. The relative standard deviations (RSD) of five replicates were less than 20% for almost all analytes at different concentrations in lean fish, fatty fish and bivalves. Most analytes showed satisfactory accuracy. Alachlor herbicide was found in samples of seabass, mussels, clams and parati with levels ranging between 0.55 to 420.39 µg kg-1 dw. Ethion was found in parati (maximum 211.22 µg kg-1 dw), mussels (15.1 µg kg-1 dw) and clams (maximum 44.50 µg kg-1 dw). Alachlor was found in clams (maximum 93.1 µg kg-1 dw), and bifenthrin was found in parati (maximum 43.4 µg kg-1 dw) and clams (maximum 42.21 µg kg-1 dw). The validated method was satisfactory for the determination of eleven pesticides in the fatty fish matrix, and thirteen pesticides in the samples of lean fish and bivalves. The presence of alachlor, ethion and bifenthrin stands out.


Assuntos
Bivalves , Praguicidas , Smegmamorpha , Animais , Humanos , Espectrometria de Massas em Tandem/métodos , Baías , Agroquímicos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Bivalves/química , Peixes , Praguicidas/análise , Extração em Fase Sólida/métodos
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