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1.
Arh Hig Rada Toksikol ; 74(1): 8-15, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37014685

RESUMEN

Microfiltration is a common step in liquid chromatography - tandem mass spectrometry (LC-MS), a method of choice in determining several mycotoxins in a solution at once. However, microfiltration may entail filter-analyte interactions that can affect the accuracy of the procedure, and underestimate exposure. The aim of our study was to assess how five different membrane materials for syringe filters (nylon, polytetrafluoroethylene, polyethersulphone, mixed cellulose ester, and cellulose acetate) affect microfiltration and recovery of EU-regulated mycotoxins, including aflatoxins B1, B2, G1, and G2, deoxynivalenol, fumonisins B1 and B2, zearalenone, T-2 and HT-2 toxins, and ochratoxin A. Polytetrafluoroethylene filters turned out to least affect microfiltration through mycotoxin loss, followed by more commonly used nylon filters, whereas the remaining three filter membrane materials had such a negative effect on recoveries that we found them incompatible with the procedure. Our findings clearly suggest that it is important to select a proper filter type that suits analyte properties and solution composition and to discard the first few filtrate drops to ensure the accuracy of the analytical procedure.


Asunto(s)
Micotoxinas , Zearalenona , Micotoxinas/análisis , Nylons/análisis , Espectrometría de Masas en Tándem/métodos , Cromatografía Liquida/métodos , Zearalenona/análisis , Cromatografía Líquida de Alta Presión/métodos
2.
J Sep Sci ; 46(1): e2200282, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36337037

RESUMEN

In toxicological analysis, the analytical validation method is important to assess the exact risk of contaminants of emerging concern in the environment. Syringe filters are mainly used to remove impurities from sample solutions. However, the loss of analyte to the syringe filter could be considerable, causing an underestimate of the analyte concentrations. The current study develops and validates simultaneous liquid chromatography-mass spectrometry analysis using a direct filtration method to detect four groups of contaminants of emerging concern. The adsorption of the analyte onto three different matrices and six types of syringe filters is reported. The lowest adsorption of analytes was observed in methanol (16.72%), followed by deionized water (48.19%) and filtered surface lake water (48.94%). Irrespective of the type of the matrices, the lowest average adsorption by the syringe filter was observed in the 0.45 µm polypropylene membrane (15.15%), followed by the 0.20 µm polypropylene membrane (16.10%), the 0.20 µm regenerated cellulose (16.15%), the 0.20 µm polytetrafluoroethylene membrane (47.38%), the 0.45 µm nylon membrane (64.87%) and the 0.20 µm nylon membrane (71.30%). In conclusion, the recommended syringe filter membranes for contaminants of emerging concern analysis are polypropylene membranes and regenerated cellulose, regardless of the matrix used.


Asunto(s)
Nylons , Polipropilenos , Nylons/análisis , Cromatografía Liquida , Filtración , Espectrometría de Masas , Agua/análisis
3.
Sci Rep ; 12(1): 16940, 2022 10 08.
Artículo en Inglés | MEDLINE | ID: mdl-36209226

RESUMEN

Charcoal is a popular form of biofuel embraced for domestic and industrial purposes. However, the use of Charcoal has some associated challenges, such as the required charcoal pot and setting it into the fire at first by using Charcoal-Ignition-Aiders (CIA) (e.g. discarded paper, nylon, rubber, plastics, petrol, the residue of processed palm oil, maise cob, wood, and kerosene). Coupled with the chemical properties of Charcoal, the resulting gases from CIA are capable of polluting the environment with perceived Adverse-Health-Implications (AHI) on the ecosystem. Therefore, this study conducted a safety assessment of charcoal biofuel usage and the effects of common CIA on combustion indices. This study followed standard methods and the use of peculiar equipment. This study established that Charcoal is commonly used in the studied area because it is cheap, readily available and requires less technical know-how. Considering the combustion indices, using paper as a CIA generated the lowest carbon monoxide (CO) value, 28.1 ppm, with 3,434.54 ppm volatile organic compound, VOC. Compared with the ACGIH standard permissible exposure level of ≤ 30 ppm, the paper gave a lesser CO value of 28.10 ppm among all the CIA. At the same time, all the CIA recorded higher VOC compared with EPA standard permissible exposure level of ≤ 15 ppm. ANOVA analysis conducted on the socio-demographic profile of the respondents, cooking attributes of the respondents, and use of charcoal pot types by the respondents in Zone 1, Zone 2, and Zone 3 gave p-values of 0.032, 0.028, and 0.039, respectively. These imply significant differences within the zones in each of the indices. The average energy content reported for charcoals sourced from oak trees, afara, obeche, mahogany, and iroko woods is 3,2149 kJ/kg compared to the lower ones. Therefore, this study recommended using these charcoals alongside discarded paper as CIA because they are a better combination to reduce AHI.


Asunto(s)
Contaminantes Atmosféricos , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/análisis , Biocombustibles/análisis , Monóxido de Carbono/análisis , Carbón Orgánico/química , Ecosistema , Gases/análisis , Queroseno/análisis , Nylons/análisis , Aceite de Palma , Goma , Compuestos Orgánicos Volátiles/análisis
4.
Sci Rep ; 12(1): 12993, 2022 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-35906265

RESUMEN

In the scientific context, the environmental and healthy impact of polymers is more related to the residual monomer content rather than their macromolecular structure, due to the monomer capability to interact with membrane cells. For this a novel method to stabilize and quantify residual monomeric isocyanates in high thermal resistance polyamide resins (PAs) has been developed. This new analytical method resulted in an improvement concerning the quantification of residual aromatic diisocyanates in viscous polymeric matrices by using a simple and cheap technique like HPLC-VWD. Diisocyanate monomers were derivatized with dibutylamine, resulting in stable urea derivatives that were simultaneously analysed and quantified. The method was applied to solvent-based polyamide resins, used as primary electrical insulation, for avoiding additional step of solvent removing before the analysis. The quantification of residual monomers answers to the provisions imposed by European Regulation N. 1907/2006 (REACH) for polymer registration, and the necessity of an early evaluation of the occupational risk associated with the use of diisocyanates, due to their toxicity and high reactivity towards moisture.


Asunto(s)
Isocianatos , Nylons , Cromatografía Líquida de Alta Presión/métodos , Nylons/análisis , Resinas de Plantas , Solventes
5.
Sci Rep ; 11(1): 8210, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33859258

RESUMEN

Generation 4 of polyamidoamine dendrimer (G4-PAMAM) has several biological effects due to its tridimensional globular structure, repetitive branched amides, tertiary amines, and amino-terminal subunit groups liked to a common core. G4-PAMAM is cytotoxic due to its positive charges. However, its cytotoxicity could increase in cancer cells due to the excessive intracellular negative charges in these cells. Furthermore, this work reports G4-PAMAM chemical structural characterization using UHPLC-QTOF-MS/MS (LC-MS) by electrospray ionization to measure its population according to its positive charges. Additionally, the antiproliferative effects and intracellular localization were explored in the HMC-1 and K-562 cell lines by confocal microscopy. The LC-MS results show that G4-PAMAM generated multivalent mass spectrum values, and its protonated terminal amino groups produced numerous positive charges, which allowed us to determine its exact mass despite having a high molecular weight. Additionally, G4-PAMAM showed antiproliferative activity in the HMC-1 tumor cell line after 24 h (IC50 = 16.97 µM), 48 h (IC50 = 7.02 µM) and 72 h (IC50 = 5.98 µM) and in the K-562 cell line after 24 h (IC50 = 15.14 µM), 48 h (IC50 = 14.18 µM) and 72 h (IC50 = 9.91 µM). Finally, our results showed that the G4-PAMAM dendrimers were located in the cytoplasm and nucleus in both tumor cell lines studied.


Asunto(s)
Dendrímeros/farmacología , Leucemia/tratamiento farmacológico , Leucemia/metabolismo , Nylons/farmacología , Antineoplásicos/análisis , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Línea Celular Tumoral , Cromatografía Liquida , Dendrímeros/análisis , Dendrímeros/farmacocinética , Ensayos de Selección de Medicamentos Antitumorales/métodos , Humanos , Concentración 50 Inhibidora , Espacio Intracelular/efectos de los fármacos , Espacio Intracelular/metabolismo , Células K562 , Leucemia/patología , Nylons/análisis , Nylons/farmacocinética , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem , Distribución Tisular
6.
Food Chem ; 345: 128625, 2021 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-33601649

RESUMEN

Small molecules in food contact materials may migrate into food during their contact. To extensively analyze the migrants, non-targeted screening is needed to detect the migrants. The migrants' detection is difficult because of the complexity and the trace amount of the migrants. In this work, the dissolution precipitation method was used to extract small molecules in Polyamide (PA) kitchenware. The extract solutions were screened by ultra-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry (UPLC-QTOF-MS) for non-targeted analysis and 64 different small molecules in materials were identified through the screening of a self-built database. Then, migration tests were performed to analyze migrants in food simulants. It suggests that the abundance of PA oligomers was the highest in migrants. The risk assessment of migrants revealed that the exposure of most migrants was at a safer level unlike the exposure of PA oligomers that exceeded their threshold of toxicological concern (TTC).


Asunto(s)
Contaminación de Alimentos/análisis , Nylons/análisis , Cromatografía Líquida de Alta Presión , Embalaje de Alimentos , Espectrometría de Masas/métodos , Medición de Riesgo
7.
Int J Legal Med ; 135(3): 885-892, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-32734474

RESUMEN

Textiles damage analysis is a very valuable tool in forensic investigations. However, to date, very little research has been carried out to understand the impact of bullet causing damages to clothing. According to the review of the most recent scientific papers, the frictional heating and crushing action of a bullet passing through synthetic fibres cause a unique transformation in their ends called mushroom-shaped morphology. In this study, the textile remains of six individuals executed during the first decade of the Chilean military dictatorship period (1973-1990) were analysed. The purpose was to examine their clothing in order to describe the fibre defects in the bullet holes. The fibres were directly observed using two different models of stereomicroscopy (MZ16A and EZ4D, Leica Microsystem Ltd., Wetzlar, Germany) and through a combination of transmitted, oblique and co-axial illumination (with Leica DFC500 Digital Camera), at × 230 and at a resolution of up to 840 Lp/mm. The mushroom-shaped morphology, along with rupturing of yarns, fibrillation or splitting of fibres, was observed in the bullet holes. Although the mushroom-shaped is a useful pattern for bullet hole identification in synthetic fibres, further research needs to be performed for developing a sounder interpretational framework of this type of forensic evidence.


Asunto(s)
Vestuario , Balística Forense/métodos , Nylons/análisis , Poliésteres/análisis , Heridas por Arma de Fuego , Adulto , Chile/etnología , Humanos , Masculino , Microscopía , Persona de Mediana Edad
8.
São José dos Campos; s.n; 2020. 86 p. il., graf., tab..
Tesis en Portugués | BBO - Odontología | ID: biblio-1151413

RESUMEN

O uso de próteses fixas adesivas é uma opção de tratamento reabilitador em casos de ausência dentária. A resina composta é um material com boas características mecânicas e estéticas, mas se faz necessário a utilização de reforços para proporcionar maior resistência ao conjunto. O presente estudo teve como objetivo avaliar a carga máxima de fratura quando da utilização de um sistema de reforço de sílica-nylon em próteses fixas adesivas confeccionadas em resina composta indireta. O estudo in vitro simulou uma prótese fixa adesiva de três elementos anterior (A) e posterior (P). Dessa forma, foram confeccionados 80 espécimes distribuídos em 8 grupos experimentais (n=10), tendo como variáveis a presença do sistema de reforço em sílica-nylon (R) e a ciclagem mecânica da peça protética (C). O processo de envelhecimento foi realizado através da ciclagem mecânica por 106 ciclos a 4 Hz (ERIOS ER-11000 Plus, São Paulo, Brasil). As amostras foram submetidas ao ensaio de resistência à carga máxima de fratura na máquina de ensaio universal (EMIC DL 1000, EMIC, Brasil) com uma célula de carga de 1000 Kgf e foram feitas análises das amostras após a fratura em estereomicroscópio (Discovery V20 CarlZeiss, Jena, Alemanha) e Microscopia Eletrônica de Varredura (Inspect S 50, FEI Company, Brno, República Tcheca). A análise estatística foi constituída pela análise de variância (ANOVA) e teste Tukey 5%. O estudo in silico foi realizado através da Análise em Elementos Finitos (FEA), onde os dentes pilares e as próteses foram escaneados (Ceramill Map 400, Amann Girrbach) e transferidos para o software CAD Rhinoceros (version 4.0SR8; McNeel North America, Seattle, WA), para elaboração do modelo volumétrico 3D e posteriormente a análise foi feita através do Software Ansys 19.3 (ANSYS, Inc. Southpointe, Canonsburg, EUA). Os resultados de resistência à carga máxima de fratura foram (N): A=163,55; AC=184,48; AR=198,81; ARC=192,24; P=539,99; PC=359,61; PR=541,74 e PRC=608,74. Foi constatado que houve diferença estatística na presença do reforço tanto nos grupos da região anterior (p=0,025), quanto da região posterior (p=0,001). Os resultados de tensão máxima principal, obtidos no FEA, foram (MPa): A=53,24/122,40; AR=55,07/117,70; P=33,28/36,18 e PR=28,06/42,87. Concluiu-se que a incorporação da malha de sílica-nylon aumentou a resistência à carga máxima de fratura das próteses fixas adesivas, independente da área em que se encontra, e os resultados obtidos no FEA corroboraram com os encontrados no teste in vitro o que permite concluir que houve validação do teste in silico(AU)


The use of resin-bonded fixed dental prostheses is a rehabilitative treatment option in cases of missing teeth. Composite resin is a material with good mechanical and aesthetic characteristics, but it is necessary to use reinforcements to provide greater resistance to the prosthesis. The present study aims to evaluate the maximum fracture load using a silica-nylon reinforcement system on resin-bonded fixed dental prostheses made of indirect composite resin. In vitro test simulated an anterior (A) and posterior (P) three-element resin-bonded fixed dental prostheses. Thus, 80 specimens were made in 8 experimental groups (n = 10), with variables the presence of the silica-nylon reinforcement system (R) and the mechanical cycling of the prosthesis (C). The aging process was performed through mechanical cycling for 106 cycles at 4 Hz (ERIOS ER-11000 Plus, São Paulo, Brazil). The samples were tested by maximum fracture load in the universal test machine (EMIC DL 1000, EMIC, Brazil) with a 1000 Kgf load cell and analyzed by stereomicroscope (Discovery V20 CarlZeiss, Jena, Germany) and Scanning Electron Microscopy (Inspect S 50, FEI Company, Brno, Czech Republic). Statistical analysis consisted of analysis of variance (ANOVA) and Tukey test 5%. In silico study was performed by Finite Element Analysis (FEA), where the abutment teeth and the prostheses were scanned (Ceramill Map 400, Amann Girrbach) and transferred to the CAD Rhinoceros (version 4.0SR8; McNeel North America, Seattle, WA) for the elaboration of the 3D volumetric model and the analysis test was made in the Ansys Software 19.3 (ANSYS, Canonsburg, PA, USA). The results of resistance to the maximum fracture load were (N): A=163,55; AC=184,48; AR=198,81; ARC=192,24; P=539,99; PC=359,61; PR=541,74 and PRC=608,74. It was found that there was a statistical difference in the presence of reinforcement in both the anterior region (p=0,025) and posterior region groups (p=0,001). The maximum main stress results obtained in the FEA were (MPa): A=53,24/122,40; AR=55,07/117,70; P=33,28/36,18 and PR=28,06/42,87. It was concluded that the incorporation of the silica-nylon mesh increased the resistance to maximum fracture load of the resin-bonded fixed dental prostheses regardless of the area it is located, and the results obtained in the FEA corroborated the results of in vitro test, which allows to conclude that the in silico test was validated(AU)


Asunto(s)
Dentadura Parcial Fija con Resina Consolidada/efectos adversos , Ensayo de Materiales/métodos , Resinas Compuestas/administración & dosificación , Análisis de Elementos Finitos/estadística & datos numéricos , Nylons/análisis
9.
Environ Monit Assess ; 191(11): 652, 2019 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-31628537

RESUMEN

In the last few years, several studies have investigated microplastics (MPs) in marine ecosystems, but data monitoring and assessing the occurrence in freshwater environments are still scarce. The present study aims to investigate the occurrence, distribution, and chemical composition of MP pollution in Vesijärvi lake and Pikku Vesijärvi pond close to the city of Lahti (Finland) in winter. Sediment, snow, and ice core samples were collected near the shore of these two aquatic systems. MPs were analysed and identified by a non-destructive method using Fourier transform infrared spectroscopy (FTIR) 2D imaging. The mean concentrations of MPs detected in sediment, snow, and ice samples were 395.5 ± 90.7 MPs/kg, 117.1 ± 18.4 MPs/L, and 7.8 ± 1.2 MPs/L, respectively. FTIR results showed the predominant abundance of microplastics, such as polyamides (up to 53.3%), polyethylene and polypropylene (up to 17.1%), and natural fragments such as cellulose (up to 45.8%) and wool (up 18.8%) in the same size range. The potential release of MPs arising from stormwaters and sport and recreational activities was evidenced.


Asunto(s)
Monitoreo del Ambiente/métodos , Microplásticos/análisis , Estanques/química , Contaminantes Químicos del Agua/análisis , Contaminación Química del Agua/análisis , Animales , Celulosa/análisis , Ecosistema , Finlandia , Lagos/química , Nylons/análisis , Polietileno/análisis , Polipropilenos/análisis , Espectroscopía Infrarroja por Transformada de Fourier
10.
Environ Pollut ; 255(Pt 1): 113133, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31536879

RESUMEN

As a new type of emerging pollutant in the ocean, microplastics have received global attention in recent years. Considering the increasing amount of human activities around the South China Sea, it is important to determine the current status of microplastic pollution in this region. In this study, we analyzed the abundance and distribution of microplastics at Zhubi Reef in the South China Sea. Microplastic abundance ranged from 1400 to 8100 items/m3 of surface water, which was much higher than the values reported from other ocean areas. About 80% of the microplastics were smaller than 0.5 mm in size. Fibers and pellets comprised the most common microplastic types. The dominant microplastics were transparent or blue in color. The main polymer types were polypropylene (25%) and polyamide (18%). In general, our results revealed Zhubi Reef was contaminated with microplastics, which were likely derived from the intensive fisheries in the area and emissions from coastal cities. This study also provides baseline data that are useful for additional studies of microplastics in the South China Sea.


Asunto(s)
Monitoreo del Ambiente/métodos , Microplásticos/análisis , Contaminantes Químicos del Agua/análisis , Contaminación Química del Agua/análisis , China , Ciudades , Arrecifes de Coral , Nylons/análisis , Polipropilenos/análisis
11.
Mar Pollut Bull ; 142: 112-118, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31232283

RESUMEN

This study undertook to investigate the occurrence of microplastics (MPs) in the high and low-tide sediments of five coastal areas in Tamil Nadu, India. The abundance of microplastics vary from 439 ±â€¯172 to 119 ±â€¯72 (HTL) and 179 ±â€¯68 to 33 ±â€¯30 (LTL) items kg-1 of sediments. The MP polymers found in the study sites are Polyethylene (73.2%), polypropylene (13.8%), nylon (8.2%), polystyrene (2.8%) and polyester (2%). The weathered surfaces might act as high-capacity carriers and this was confirmed by SEM-EDAX. The results of an analysis of the textures of the sediments do not ascribe any influence on microplastic abundance. The recreation, religious and fishing activities are the major contributors to plastic pollution in these beaches, which is borne out by the high abundance of MPs in the study sites. A regular and permanent waste management system should be put in place for the protection of beaches.


Asunto(s)
Sedimentos Geológicos/análisis , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Playas , Biodegradación Ambiental , Monitoreo del Ambiente/métodos , Sedimentos Geológicos/química , India , Microscopía Electrónica de Rastreo , Nylons/análisis , Plásticos/metabolismo , Poliésteres/análisis , Polietileno/análisis , Polipropilenos/análisis , Poliestirenos/análisis , Contaminantes Químicos del Agua/metabolismo
12.
Mar Pollut Bull ; 141: 501-513, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30955761

RESUMEN

Microplastics (MP) in sediments from discharge sites for wastewater and deposition sites in deep regions in an urban fjord in Norway were extracted by density separation in a Microplastic Sediment Separator with ZnCl2. Particles (>11 µm) were identified using FTIR. Twenty different polymer types were identified, at concentrations from 12,000 to 200,000 particles kg-1 dw. Over 95% of the MP were smaller than 100 µm. High deposition of small MP agreed with known areas for organic deposition. Polyurethane acrylate resins dominated the small MP while polyamide fibers dominated the larger MP. Particles >500 µm showed different maximum concentrations and spatial distribution from the smaller particles. This study is the first to report concentration ranges of identified plastic particles from a Norwegian fjord, down to sizes below the limit of visual identification. The results provides a baseline for future comparison, and point at relevant sizes for environmental risk assessments.


Asunto(s)
Sedimentos Geológicos/análisis , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Estuarios , Sedimentos Geológicos/química , Noruega , Nylons/análisis , Tamaño de la Partícula , Poliuretanos/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Aguas Residuales
13.
Chemosphere ; 224: 637-645, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30849624

RESUMEN

Microplastic research in urban and industrial areas, including remote areas, have been conducted recently. However, there is still a lack of research about microplastic abundances in slum area. Ciwalengke River is located in Majalaya, Indonesia, which is dominated by slum and industrial areas that probably generate microplastics. This research was conducted to investigate the distribution of microplastic around the slum area for the first time. Surface water and sediment samples of the river were obtained at ten locations and grouped into six segments location based on different land use at the riverbank. Microplastic particles were identified using binocular microscope and categorized by shape and size. The average microplastic concentration were 5.85 ±â€¯3.28 particles per liter of surface water and 3.03 ±â€¯1.59 microplastic particles per 100 g of dry sediments. Microplastic concentration in the sediment samples were found to have significant differences in location segment (Kruskal Wallis test, p-value = 0.01165 < 0.05), but no significant differences were found in the water samples (Kruskal Wallis test; p-value = 0.654 > 0.05). In addition, microplastic distribution was dominated by fiber particle. More fiber shape might be derived from the direct clothing of residents in the river and fabric washing process in the textile industries. This was also revealed by Raman spectroscopy test of several microplastic particles indicating that the type of microplastic were polyester and nylon.


Asunto(s)
Plásticos/análisis , Ríos/química , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/métodos , Sedimentos Geológicos/química , Indonesia , Industrias , Nylons/análisis , Plásticos/química , Poliésteres/análisis , Áreas de Pobreza
14.
Environ Pollut ; 244: 766-773, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30388680

RESUMEN

Reported here is the first evidence of plastic ingestion by freshwater fishes in the Amazon. Plastic bags, bottles, fishing gear, and other products are entering Amazonian water bodies and degrade into meso- and micro-plastic particles that may be ingested, either directly or indirectly via food chains, by fishes. Examination of stomach contents from 172 specimens of 16 serrasalmid species from lower Xingu River Basin revealed consumption of plastic particles by fishes in each of three trophic guilds (herbivores, omnivores, carnivores). Overall, about one quarter of specimens and 80% of species analyzed had ingested plastic particles ranging from 1 to 15 mm in length. Fourier transform infrared spectroscopy indicated 12 polymer types, including 27% identified as polyethylene, 13% polyvinyl chloride, 13% polyamide, 13% polypropylene, 7% poly(methyl methacrylate), 7% rayon, 7% polyethylene terephtalate, and 13% a blend of polyamide and polyethylene terephtalate. Dimensions of ingested plastic particles varied among trophic guilds, even though the frequency and mass of ingested particles were not significantly different among fishes with different feeding habits.


Asunto(s)
Characiformes/fisiología , Monitoreo del Ambiente/métodos , Contenido Digestivo/química , Plásticos/análisis , Plásticos/toxicidad , Residuos/análisis , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad , Animales , Celulosa/análisis , Ingestión de Alimentos , Peces , Cadena Alimentaria , Nylons/análisis , Polietileno/análisis , Tereftalatos Polietilenos/análisis , Polimetil Metacrilato/análisis , Polipropilenos/análisis , Cloruro de Polivinilo/análisis , Ríos/química , Alimentos Marinos
15.
Environ Pollut ; 244: 503-512, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30366298

RESUMEN

Although evidence suggests the ubiquity of microplastics in the marine environment, our knowledge of its occurrence within remote habitats, such as the deep sea, is scarce. Furthermore, long term investigations of microplastic abundances are even more limited. Here we present a long-term study of the ingestion of microplastics by two deep-sea benthic invertebrates (Ophiomusium lymani and Hymenaster pellucidus) sampled over four decades. Specimens were collected between the years 1976-2015 from a repeat monitoring site >2000 m deep in the Rockall Trough, North East Atlantic. Microplastics were identified at a relatively consistent level throughout and therefore may have been present at this locality prior to 1976. Considering the mass production of plastics began in the 1940s - 50s our data suggest the relatively rapid occurrence of microplastics within the deep sea. Of the individuals examined (n = 153), 45% had ingested microplastics, of which fibres were most prevalent (95%). A total of eight different polymer types were isolated; polyamide and polyester were found in the highest concentrations and in the majority of years, while low-density polystyrene was only identified in 2015. This study provides an assessment of the historic occurrence of microplastics on the deep seafloor and presents a detailed quantification and characterisation of microplastics ingested by benthic species. Furthermore these data advance our knowledge on the long-term fate of microplastic in marine systems.


Asunto(s)
Monitoreo del Ambiente , Contenido Digestivo/química , Plásticos/análisis , Polímeros/aislamiento & purificación , Estrellas de Mar/fisiología , Contaminantes Químicos del Agua/análisis , Contaminación Química del Agua/análisis , Animales , Océano Atlántico , Ingestión de Alimentos , Ecosistema , Nylons/análisis , Poliésteres/análisis , Poliestirenos/análisis , Contaminantes Químicos del Agua/aislamiento & purificación
16.
Mar Pollut Bull ; 136: 472-476, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30509831

RESUMEN

This study provides the first evidence of nylon filament occurrence in the stomach of an economically important target shrimp species in the Mediterranean Sea, Plesionika narval (Fabricius, 1787). Samples were collected monthly from November 2014 to October 2015 from shallow (10-30 m) and deeper waters (150-170 m). The occurrence of plastics in the stomachs of the Narwal shrimp was 5.93% and identified as Nylon by FT-IR analysis. Higher percentages of ingested plastics were found in females from shallower depths and in males from deeper waters. The maximum number of plastics was recorded in January and March, possibly related to the higher feeding intensity of females prior to their reproduction period. A total of 10.3% of females and 4.8% of males with ingested plastics had almost empty stomachs. The presence of plastics in the stomach of P. narval is an evidence of passive ingestion which in this study related to fishing activities.


Asunto(s)
Contenido Digestivo/química , Pandalidae , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Animales , Exposición Dietética/análisis , Ingestión de Alimentos , Monitoreo del Ambiente/métodos , Femenino , Masculino , Mar Mediterráneo , Nylons/análisis , Reproducción , Mariscos/análisis , Espectroscopía Infrarroja por Transformada de Fourier
17.
Mar Pollut Bull ; 137: 180-184, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30503424

RESUMEN

Marine debris is widespread in oceans worldwide, including the most remote locations. Here, for the first time, we report macro-debris accumulation on beaches of Trindade Island, a remote island 1160 km from mainland Brazil. High debris density was recorded on windward, east-coast beaches, which are exposed to wind-driven currents. Small-sized plastic fragments were the most abundant debris. Polyethylene (67%), polypropylene (30%) and polyamide (3%) were the most prevalent polymeric materials identified by ATR-FTIR. Identified debris show that interaction with Trindade fauna, mainly with seabirds and endangered terrestrial crabs, exists and already has some impact. This study provides baseline information on Trindade macro-debris demonstrating that the island, located on the edge of the South Atlantic Gyre, acts as a sink for gyre debris, exposing the island fauna to the threats related to plastic contamination.


Asunto(s)
Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Brasil , Monitoreo del Ambiente , Humanos , Nylons/análisis , Océanos y Mares , Polietileno/análisis , Polipropilenos/análisis , Agua de Mar/química
18.
Mar Pollut Bull ; 137: 444-448, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30503453

RESUMEN

Microplastic particles are abundant marine pollutants that are ingested by many seabirds. Some seabirds regurgitate non-digestible materials in the form of pellets and their analysis may be useful to study the abundance of plastic debris at the local scale. Here, we aimed to provide baseline data for the presence of microplastics in pellets regurgitated by European shags (Phalacrocorax aristotelis) (n = 41) in the Iberia peninsula (NW Spain). We found microplastic fibers in 63% of pellets, suggesting that this type of plastic pollution is prevalent in the study area. According to Fourier Transform Infrared spectrometry, nylon fibers were the most abundant, followed by polyester. We also found that the presence of microplastics was higher in pellets containing remains of benthic fishes. Our results suggest that shag pellets may be useful to monitor microplastic pollution in coastal waters.


Asunto(s)
Aves/fisiología , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Animales , Ingestión de Alimentos , Monitoreo del Ambiente , Nylons/análisis , España , Residuos/análisis
19.
Mar Pollut Bull ; 137: 610-616, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30503475

RESUMEN

This is the first study on the distribution and characteristics of plastic debris found in the sediments of Rameswaram Island, Gulf of Mannar, India. Studies on the distribution of plastics and microplastic content in highly populated coral islands and their impact on the coral ecosystem are very scarce. For this purpose, marine sediment samples were collected from 20 locations along the coastal areas of the study region. The distribution and characterization study was carried out by visual examination followed by FTIR spectroscopy. The results showed abundance of white-colored and irregular-shaped plastic debris in this study area. Polypropylene was identified as a dominant polymer variety, followed by polyethylene, polystyrene, nylon, and polyvinyl chloride. Tourist activities and fishing practices were found to be the possible sources of the microplastic debris. Additionally, the distribution of the plastics was found to be dominantly controlled by the aeolian process and the nature of the coast.


Asunto(s)
Sedimentos Geológicos/análisis , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Playas , Arrecifes de Coral , Ecosistema , India , Islas , Nylons/análisis , Polietileno/análisis , Polipropilenos/análisis , Poliestirenos/análisis , Cloruro de Polivinilo/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Residuos/análisis
20.
Mar Pollut Bull ; 135: 451-457, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30301058

RESUMEN

The first report on the emergence of microplastic in Malaysian marine waters was documented in this study. Water samples were collected from two regions, namely Kuala Nerus and Kuantan port, as the representatives of different anthropogenic activities. Identification of microplastic was performed based on physical characteristics (colour, shape, density) and chemical characterisation (ATR-FTIR analysis) for a functional group of polymers. Fragment type, black or grey colour and high density (>1.02 g cm-3) of microplastic were the most prevalent characteristics found in both areas. Two principal components (density and colour) rendered explained about 95.3% (Kuantan) and 95.6% (Kuala Nerus) of the total variance. Six possible polymer materials were identified, namely polyester, polystyrene, polyamide, polyvinyl chloride, polypropylene, and polyethylene. The findings of the study provided good baseline information on marine debris issue in Malaysia.


Asunto(s)
Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Malasia , Nylons/análisis , Poliésteres/análisis , Polietileno/análisis , Polímeros/análisis , Poliestirenos/análisis , Agua de Mar/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Residuos/análisis , Contaminantes Químicos del Agua/química
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