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1.
J Sci Food Agric ; 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38437521

RESUMEN

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.

2.
Sci Total Environ ; 905: 167704, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-37820801

RESUMEN

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.


Asunto(s)
Delfines , Retardadores de Llama , Animales , Retardadores de Llama/análisis , Brasil , Monitoreo del Ambiente , Cetáceos , Éteres Difenilos Halogenados/análisis
3.
Sci Rep ; 13(1): 12490, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37528136

RESUMEN

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.

4.
Sensors (Basel) ; 23(10)2023 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-37430513

RESUMEN

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.

5.
Chemosphere ; 328: 138575, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37011823

RESUMEN

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.


Asunto(s)
Hidrocarburos Clorados , Humanos , Animales , Hidrocarburos Clorados/análisis , Parafina/análisis , Ecosistema , Estuarios , Argentina , Brasil , Monitoreo del Ambiente , Lípidos , China
6.
Micromachines (Basel) ; 14(2)2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36838063

RESUMEN

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.

7.
Artículo en Inglés | MEDLINE | ID: mdl-36497865

RESUMEN

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.


Asunto(s)
Bivalvos , Plaguicidas , Smegmamorpha , Animales , Humanos , Espectrometría de Masas en Tándem/métodos , Bahías , Agroquímicos , Cromatografía de Gases y Espectrometría de Masas/métodos , Bivalvos/química , Peces , Plaguicidas/análisis , Extracción en Fase Sólida/métodos
8.
Nanomaterials (Basel) ; 12(18)2022 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-36144960

RESUMEN

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.

9.
Environ Res ; 214(Pt 4): 114157, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36027956

RESUMEN

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).


Asunto(s)
Contaminantes Ambientales , Fluorocarburos , Spheniscidae , Animales , Regiones Antárticas , Monitoreo del Ambiente/métodos , Plumas/química , Fluorocarburos/análisis
11.
An Acad Bras Cienc ; 94(suppl 2): e20211215, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35730899

RESUMEN

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.


Asunto(s)
Contaminación por Petróleo , Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Accidentes , Organismos Acuáticos , Monitoreo del Ambiente , Humanos , Contaminación por Petróleo/efectos adversos , Contaminación por Petróleo/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/toxicidad , Medición de Riesgo , Alimentos Marinos/análisis , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
12.
Environ Res ; 210: 112886, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35150711

RESUMEN

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.


Asunto(s)
Disruptores Endocrinos , Retardadores de Llama , Animales , Disruptores Endocrinos/análisis , Éteres Difenilos Halogenados/análisis , Organofosfatos , Alimentos Marinos/análisis
13.
Chemosphere ; 291(Pt 3): 132674, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34736745

RESUMEN

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.


Asunto(s)
Ácidos Alcanesulfónicos , Contaminantes Ambientales , Fluorocarburos , Brasil , Comercio , Fluorocarburos/análisis , Internacionalidad , Contaminantes Orgánicos Persistentes
14.
Sci Total Environ ; 803: 149744, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-34482147

RESUMEN

Pharmaceuticals (PhACs) are considered emerging contaminants with potential accumulation in aquatic organisms. Thus, seafood consumption may cause long-term effects and health risk for consumers. In the present study, the occurrence of PhACs in seafood from two Brazilian coastal areas, Sepetiba Bay (n = 43) and Parnaiba Delta River (n = 48), was determined for the first time, and their potential risk for human health was assessed. An eco-friendly multi-analytes method was used, after being validated for the different types of matrices (mussels, fatty and lean fish). All compounds under study were detected at least in four seafood species, including chloramphenicol, an antibiotic prohibited in animal foods. Most PhACs had mean concentrations below limit of quantification. Ibuprofen and other nonsteroidal anti-inflammatory drugs (NSAIDs), as well as simvastatin and carbamazepine were the main PhACs bioaccumulated in edible parts of seafood species from Brazil. The high trophic level carnivorous species, snook, was the most contaminated by NSAIDs, while bivalves were the seafood more contaminated by lipid regulators. The profile of contamination did not vary among different types of matrix, except in relation to carbamazepine and ketoprofen. These PhACs were more abundant in species from Sepetiba Bay, an area highly impacted by human influence. The estimated daily exposure for Brazilian population that consumes the studied species was up to 20.3 ng/kg bw/day via carib pointed-venus and 25.7 ng/kg bw/day via snooks, lower than acceptable daily intake. Thus, consumption of seafood species from Sepetiba Bay and Parnaiba Delta River seems to be safe to the population in what concerns the PhACs studied.


Asunto(s)
Preparaciones Farmacéuticas , Contaminantes Químicos del Agua , Animales , Brasil , Monitoreo del Ambiente , Humanos , Medición de Riesgo , Alimentos Marinos/análisis , Contaminantes Químicos del Agua/análisis
15.
Chemosphere ; 287(Pt 3): 132344, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34826954

RESUMEN

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.


Asunto(s)
Hidrocarburos Clorados , Parafina , Brasil , China , Monitoreo del Ambiente , Humanos , Hidrocarburos Clorados/análisis , Parafina/análisis
16.
Nanomaterials (Basel) ; 11(11)2021 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-34835675

RESUMEN

The evolution of nanotechnology has provided a better understanding of light-matter interaction at a subwavelength scale and has led to the development of new devices that can possibly play an important role in future applications. Nanoantennas are an example of such devices, having gained interest in recent years for their application in the field of photovoltaic technology at visible and infrared wavelengths, due to their ability to capture and confine energy of free-propagating waves. This property results from a unique phenomenon called extraordinary optical transmission (EOT) where, due to resonant behavior, light passing through subwavelength apertures in a metal film can be transmitted in greater orders of magnitude than that predicted by classical theories. During this study, 2D and 3D models featuring a metallic nanoantenna array with subwavelength holes coupled to a photovoltaic cell are simulated using a Finite Element Tool. These models present with slight variations between them, such as the position of the nanoantenna within the structure, the holes' geometry and the type of cell, in order to verify how its optical response is affected. The results demonstrate that the coupling of nanoantennas to solar cells can be advantageous and improve the capture and absorption of radiation. It is concluded that aperture nanoantennas may concentrate radiation, meaning that is possible to tune the electric field peak and adjust absorption on the main layers. This may be important because it might be possible to adjust solar cell performance to the global regions' solar spectrum by only adjusting the nanoantenna parameters.

17.
Environ Pollut ; 290: 118020, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34450491

RESUMEN

The occurrence of organochlorine pesticides (OCPs) used decades ago for vector control in urban areas is still reported as a threat to human health. Pyrethroids emerged as a replacement for OCPs in sanitary campaigns and are currently the main insecticides used for vector control worldwide, with prominent use as agricultural and household insecticides, for veterinary and gardening purposes, and as wood preservative. This study aimed to assess the occurrence, seasonal variation, and potential sources of pyrethroids in ambient air of two urban regions of Southeastern Brazil, along with the potential health risks to local populations via inhalation exposure. Pyrethroids were sampled by polyurethane foam passive air samplers and their concentrations were determined by gas chromatography coupled with electron capture negative ionization mass spectrometry (GC/ECNI-MS). Atmospheric pyrethroid concentrations (hereinafter reported in pg m-3) were considerably higher than those reported by previous studies worldwide. Cypermethrin (median: 2446; range: 461-15 125) and permethrin (655; 19-10 328) accounted for 95% of the total measured pyrethroids in ambient air. The remaining fraction comprised smaller amounts of bifenthrin (46;  urban-industrial > background areas. HQs increased with decreasing age group, but deterministic and probabilistic estimates did not identify direct health risks for any group. Nevertheless, since only inhalation exposure was considered in this work, other pathways should be investigated to provide a more comprehensive risk assessment of the human exposure to pyrethroids.


Asunto(s)
Insecticidas , Piretrinas , Atmósfera , Brasil , Monitoreo del Ambiente , Cromatografía de Gases y Espectrometría de Masas , Humanos , Exposición por Inhalación , Insecticidas/análisis , Piretrinas/análisis , Medición de Riesgo
18.
Sci Total Environ ; 788: 147820, 2021 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-34029810

RESUMEN

Polybrominated diphenyl ethers (PBDEs) and their methoxylated analogues (MeO-BDEs) are widely distributed in the environment. The main concern about the presence of PBDEs and MeO-BDEs in fish is due to their potential endocrine disruption effects in the specimens, and their potential risk to the health of human consumers. Considering these concerns, the goal of this study was to investigate the occurrence of PBDEs and MeO-BDEs in muscle tissues of blue shark (BSH), Prionace glauca, and yellowfin tuna (YFT), Thunnus albacares, caught in the Equatorial Atlantic Ocean (EAO), North-eastern Brazilian waters, and to evaluate the potential risk of human exposure by consumption. Muscle tissues of YFT and BSH were extracted using a Soxhlet apparatus and an Accelerated Solvent Extractor (ASE), respectively. PBDEs and MeO-BDEs were analysed by GC-NCI-MS. Concentrations of PBDEs ranged from not detected (nd) to 10 ng g-1 lipid weight (lw) in YFT muscle samples, while PBDE levels in BSH muscle samples ranged from

Asunto(s)
Éteres Difenilos Halogenados , Tiburones , Animales , Océano Atlántico , Brasil , Monitoreo del Ambiente , Éteres Difenilos Halogenados/análisis , Humanos , Atún
19.
Nanomaterials (Basel) ; 11(2)2021 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-33562296

RESUMEN

In the last decade, the development and progress of nanotechnology has enabled a better understanding of the light-matter interaction at the nanoscale. Its unique capability to fabricate new structures at atomic scale has already produced novel materials and devices with great potential applications in a wide range of fields. In this context, nanotechnology allows the development of models, such as nanometric optical antennas, with dimensions smaller than the wavelength of the incident electromagnetic wave. In this article, the behavior of optical aperture nanoantennas, a metal sheet with apertures of dimensions smaller than the wavelength, combined with photovoltaic solar panels is studied. This technique emerged as a potential renewable energy solution, by increasing the efficiency of solar cells, while reducing their manufacturing and electricity production costs. The objective of this article is to perform a performance analysis, using COMSOL Multiphysics software, with different materials and designs of nanoantennas and choosing the most suitable one for use on a solar photovoltaic panel.

20.
Environ Pollut ; 275: 116590, 2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33582630

RESUMEN

As humans are present in Antarctica only for scientific and tourism-related purposes, it is often described as a pristine region. However, studies have identified measurable levels of Persistent Organic Pollutants (POPs), such as organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs), in the Antarctic region. These are highly toxic anthropogenic compounds with tendency to travel long distances and reach remote environments, where they can bioaccumulate in the biota. Penguins are exposed to POPs mainly through their diet, which they partially eliminate via feathers. Species of the genus Pygoscelis occur around Antarctic continent and its surrounding regions, and can act as indicators of contaminants that reach the continent. Here, we report OCP and PCB levels in feathers of male and female penguins of P. adeliae, P. antarcticus and P. papua from King George Island, South Shetland Islands, Antarctica. Interspecific, sex- and body-size-related differences were investigated in the contamination profiles of PCBs and OCPs. Feather samples were collected from adult penguins (n = 41). Quantification of compounds was performed by gas chromatography-tandem mass spectrometry. The three Pygoscelis species presented similar contamination profiles, with higher concentrations of dichlorodiphenyltrichloroethane (∑DDT; 1.56-3.82 ng g-1 dw), lighter PCB congeners (∑PCB: 11.81-18.65 ng g-1 dw) and HCB (hexachlorobenzene: 1.65-4.06 ng g-1 dw). Amongst the three penguin species, P. antarcticus had lower and P. papua higher concentrations of most of the compounds identified. We found interspecific differences in POPs accumulation as well as sex differences in POP concentrations. Our data indicate a small but significant positive correlation between body size and the concentrations of some compounds. Despite the overall low concentrations found, this study increases knowledge of the occurrence of POPs in Antarctic penguins, thereby reinforcing concerns that Antarctica, although remote and perceived to be protected, is not free from the impact of anthropogenic pollutants.


Asunto(s)
Hidrocarburos Clorados , Plaguicidas , Bifenilos Policlorados , Spheniscidae , Animales , Regiones Antárticas , Monitoreo del Ambiente , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Hidrocarburos Clorados/análisis , Islas , Masculino , Plaguicidas/análisis , Bifenilos Policlorados/análisis
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