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The purpose of this study was to identify a characteristic elemental tyre fingerprint that can be utilised in atmospheric source apportionment calculations. Currently zinc is widely used as a single element tracer to quantify tyre wear, however several authors have highlighted issues with this approach. To overcome this, tyre rubber tread was digested and has been analysed for 25 elements by ICP-MS to generate a multielement profile. Additionally, to estimate the percentage of the tyre made up of inert fillers, thermogravimetric analysis was performed on a subset. Comparisons were made between passenger car and heavy goods vehicle tyre composition, and a subset of tyres had both tread and sidewall sampled for further comparison. 19 of the 25 elements were detected in the analysis. The mean mass fraction of zinc detected was 11.17 g/kg, consistent with previous estimates of 1% of the tyre mass. Aluminium, iron, and magnesium were found to be the next most abundant elements. Only one source profile for tyre wear exists in both the US and EU air pollution species profile databases, highlighting the need for more recent data with better coverage of tyre makes and models. This study provides data on new tyres which are currently operating on-road in Europe and is therefore relevant for ongoing atmospheric studies assessing the levels of tyre wear particles in urban areas.
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Contaminación del Aire , Goma , Goma/análisis , Monitoreo del Ambiente , Contaminación del Aire/análisis , Zinc/análisis , Vehículos a MotorRESUMEN
A simple and sensitive method based on liquid chromatography-atmospheric pressure chemical ionisation-tandem mass spectrometry (LC-APCI-MS/MS) was developed and validated to determine the levels of 13N-nitrosamines and N-nitrosatable substances migrated from rubber teats into artificial saliva. The migration test from rubber teats was conducted at 40 °C and for 24 h in artificial saliva, and the migrated artificial saliva solution was analysed by liquid chromatography tandem mass spectrometry (LC-MS/MS) without further extracting steps. The sensitivity of N-nitrosamines was examined by applying atmospheric chemical ionisation and electrospray ionisation to optimise the mass spectrometric conditions, and the atmospheric chemical ionisation (APCI) mode exhibited 1.6-19 times higher sensitivity. Method validation showed acceptable linearity, precision, and accuracy, and the detection and quantification limits were 0.07-0.35 and 0.24-1.1 µg kg-1, respectively. The developed liquid chromatography-atmospheric chemical ionisation-tandem mass spectrometry method was applied to 39 domestic and imported rubber teats. From 39 samples, N-nitrosamines [N-nitrosodimethylamine (NDMA), N-nitrosomorpholine (NMOR), and N-nitroso n-methyl N-phenylamine (NMPhA)] were detected in 30 samples, with N-nitrosatable substances in 17 samples give rise to NDMA, NMOR, and N-nitrosodiethylamine. However, the levels were below the specific migration limit of Korean Standards and Specifications for Food Containers, Utensils, and Packages and EC Directive 93/11/EEC.
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Nitrosaminas , Goma , Goma/análisis , Goma/química , Espectrometría de Masas en Tándem , Radioisótopos de Nitrógeno , Cromatografía Liquida/métodos , Saliva Artificial/análisis , Nitrosaminas/análisis , DimetilnitrosaminaRESUMEN
This study reports the seasonal variations in dry deposition of coarse and fine particles on the foliar surfaces of common indoor plants viz. Ficus elastica, Ficus lyrata, and Schefflera arboricola along with their biochemical changes in the urban households of metropolitan Delhi. The dustfall fluxes were significantly higher at the industrial site as compared to residential site and temporal variations indicated higher dustfall fluxes during the winter months as compared to other seasons. Seasonal concentrations of chlorophylls, pH, and soluble sugars were higher during monsoon season for the indoor plants whereas ascorbic acid content was higher in the winter season indicating more stress. The results of correlation plots revealed that the variations observed in the biochemical traits were interlinked with the changes in dustfall fluxes during different seasons, thereby reflecting the changes in air pollution stress faced by plant foliage. The air pollution tolerance index and anticipated performance index were evaluated to understand the overall tolerance of indoor plants toward air pollution which can be utilized in phytoremediation techniques. It was concluded that among the studied indoor plants, Ficus elastica and Ficus lyrata are better plant species than Schefflera arboricola for improving indoor air quality.
The novelty of this work lies in studying the spatial and temporal variations in the deposition of indoor dust on foliar surfaces of plants in the households of a highly polluted metropolitan. Based on the biochemical parameters, the air pollution tolerance index (APTI) and anticipated performance index (API) have been calculated for the first time for Ficus elastica, Ficus lyrata, and Schefflera arboricola. The study strengthens the existing knowledge regarding the role of leaves as a platform to capture dust particles and role of indoor plants in improving air quality. The outcomes of this study can be applied in modern day concepts for urban areas such as nature-based solutions for air pollution mitigation, vertical greenery systems (VGS), green roofs, and outdoor green walls.
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Contaminantes Atmosféricos , Contaminación del Aire , Estaciones del Año , Contaminantes Atmosféricos/análisis , Goma/análisis , Monitoreo del Ambiente/métodos , Biodegradación Ambiental , Plantas , India , Hojas de la Planta/químicaRESUMEN
Abstract The locust bean gum (LBG) is a polysaccharide with thickening, stabilizing and gelling properties and it has been used in the preparation of pharmaceutical formulations. Hydrogels (HGs) are obtained from natural or synthetic materials that present interesting properties for skin application. This study aimed to develop HGs from LBG using indole-3-carbinol (I3C) as an asset model for cutaneous application. HGs were prepared by dispersing LBG (2%, 3% and 4% w/v) directly in cold water. The formulations showed content close to 0.5 mg/g (HPLC) and pH ranging from 7.25 to 7.41 (potentiometry). The spreadability factor (parallel plate method) was inversely proportional to LBG concentration. The rheological evaluation (rotational viscometer) demonstrated a non-Newtonian pseudoplastic flow behavior (Ostwald De Weale model), which is interesting for cutaneous application. The HET-CAM evaluation showed the non-irritating characteristic of the formulations. The bioadhesive potential demonstrated bioadhesion in a concentration-dependent manner. Permeation in human skin using Franz cells showed that the highest LBG concentration improved the skin distribution profile with greater I3C amounts in the viable skin layers. The present study demonstrated the feasibility of preparing HGs with LBG and the formulation with the highest polymer concentration was the most promising to transport active ingredients through the skin.
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Polisacáridos/análisis , Goma/análisis , Hidrogeles/análisis , Potenciometría/instrumentación , Preparaciones Farmacéuticas/administración & dosificación , Cromatografía Líquida de Alta Presión/métodos , Crema para la Piel/clasificaciónRESUMEN
OBJECTIVES: In our study, we investigate the collagen structure of human pericardium microscopically in dependence of glutaraldehyde (GA) concentration and fixation time. METHODS: Pericardial samples were taken from 9 patients aged 40+ years who underwent cardiac surgery, either coronary artery bypass surgery or valve implantation/reconstruction. Specimens were cut in 5 equal pieces and treated with GA at fixed concentrations (0.3125%, 0.625%, or 1.25%) but different exposer times (5 min, 10 min, 20 min, 30 min, and 60 min). Elastica van Gieson (EvG) staining was used for microscopic examination of pericardial collagen structure. RESULTS: The collagen structure studied microscopically depended on both GA incubation time and GA concentration. At low GA concentrations (0.3125%, 0.625%) and short incubation times, individual collagen fibers appeared separately. After one hour incubation period, single collagen fibers could not be distinguished at any GA concentration. For fixed incubation times no differences were seen in the collagen structure when 0.3125% and 0.625% GA were used. However, at a concentration of 1.25% GA fusion of individual collagen fibers was already observed at low incubation times. CONCLUSION: Pericardial collagen structure changes with increasing incubation time and increasing GA concentration by raising fusion of single fibers. For GA concentrations of ≤0.625%, fiber fusion depends plainly on incubation time. That is relevant as this concentration is used in cardiac surgery. At a concentration of 1.25% GA, single collagen fibers could not be separated, even at short incubation times. Fusion of individual collagen fibers and changes in appearance (less undulating) were assumed to be responsible for stiffening of GA-fixed pericardium.
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Bioprótesis , Humanos , Glutaral/farmacología , Glutaral/análisis , Goma/análisis , Pericardio/patología , Colágeno/análisisRESUMEN
This study investigated the long-term variations in ambient levels of surface ozone, volatile organic compounds (VOCs), and nitrogen oxides (NOx) within the Houston-Galveston-Brazoria (HGB) region. Analysis of ozone levels revealed an overall reduction in the maximum daily 8-h average ozone (MDA8 O3) from 2000 to 2019 (April-October) with an average rate of â¼ -0.48 ppb/yr across HGB. With a few exceptions, the MDA8 O3 reduction rates were more pronounced for the monitoring sites closer to the Houston Ship Channel (HSC). Meanwhile, ambient levels of NOx and most VOC species (across the three representative sites as Houston Bayland Park, Haden Road, and Lynchburg Ferry) decreased significantly within the same investigation period, reflecting the impact of emission reductions. The positive matrix factorization (PMF) model applied to the mentioned sites identified regional background ozone, petrochemical emissions, engine combustion, natural gas/fuel evaporation, and solvent/painting/rubber industries as the major sources of MDA8 O3. The regional background ozone was the predominant source, accounting for 59-70% of MDA8 O3 across the three sites. Regarding the local anthropogenic emissions, natural gas/fuel evaporation was the largest contributor (19.5 ± 6.1%) to MDA8 O3 at Houston Bayland Park, whereas petrochemical facilities (10.9 ± 4.9%) and solvent/painting/rubber industries (18.1 ± 9.5%) were the largest factor at Haden Road and Lynchburg Ferry, respectively. Notable reductions were found in the contributions of petrochemical emissions, engine combustion, and natural gas/fuel evaporation to MDA8 O3 within 2000-2019, but an increasing trend was revealed in the role of solvent/painting/rubber industries on MDA8 O3 most probably due to the enhanced demand for their products. Results of this study corroborated the success of emission control policies in limiting ozone precursors and provided useful details for prioritizing emission reduction policies to further reduce ozone pollution in the HGB.
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Contaminantes Atmosféricos , Ozono , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/análisis , China , Monitoreo del Ambiente/métodos , Gas Natural/análisis , Ozono/análisis , Goma/análisis , Solventes/análisis , Compuestos Orgánicos Volátiles/análisisRESUMEN
Natural rubber (NR) is an eminent sustainable material and is the only agricultural product among various rubbers. Use of nanofillers in NR matrix as a reinforcing agent has gained huge attention because they offer excellent matrix-filler interaction upon forming a good dispersion in the NR matrix. Nanoscale dispersion of fillers lead to greater interfacial interactions between NR and fillers compared to microfillers, which in turn lead to a conspicuous reinforcing effect. Addition of various nanofillers into NR matrix improves not only the mechanical properties but also the electrical, thermal and antimicrobial properties to an extreme level. The current review describes the reinforcing ability of various nanofillers such as clay, graphene, carbon nanotube (CNT), titanium dioxide (TiO2), chitin, cellulose, barium titanate (BaTiO3) and lignin in NR matrix. Moreover, reinforcement of various hybrid nanofillers in NR is also discussed in a comprehensive manner. The review also includes the historical trajectory of rubber nanocomposites and a comprehensive account on the factors affecting the properties of the NR nanocomposites.
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Nanocompuestos/análisis , Nanocompuestos/química , Goma/análisis , Goma/química , Biopolímeros/análisis , Biopolímeros/química , Fenómenos Químicos , Análisis EspectralRESUMEN
OBJECTIVES: To examine associations between occupational exposures to rubber dust, rubber fumes and N-nitrosamines and non-cancer mortality. METHODS: A cohort of 36 441 males aged 35+ years employed in British rubber factories was followed-up to 2015 (94% deceased). Competing risk survival analysis was used to assess risks of dying from non-cancer diseases (respiratory, urinary, cerebrovascular, circulatory and digestive diseases). Occupational exposures to rubber dust, rubber fumes, N-nitrosamines were derived based on a population-specific quantitative job-exposure matrix which in-turn was based on measurements in the EU-EXASRUB database. RESULTS: Exposure-response associations of increased risk with increasing exposure were found for N-nitrosomorpholine with mortality from circulatory diseases (subdistribution hazard ratio (SHR) 1.17; 95% CI 1.12 to 1.23), ischaemic heart disease (IHD) (SHR 1.19; 95% CI 1.13 to 1.26), cerebrovascular disease (SHR 1.19; 95% CI 1.07 to 1.32) and exposures to N-nitrosodimethylamine with respiratory disease mortality (SHR 1.41; 95% CI 1.30 to 1.53). Increased risks for mortality from circulatory disease, IHD and digestive diseases were found with higher levels of exposures to rubber dust, rubber fumes and N-nitrosamines sum, without an exposure-dependent manner. No associations were observed between rubber dust, rubber fumes and N-nitrosamines exposures with mortality from asthma, urinary disease, bronchitis, emphysema, liver disease and some digestive diseases. CONCLUSIONS: In a cohort of rubber factory workers with 49 years of follow-up, increased risk for mortality from circulatory, cerebrovascular, respiratory and digestive diseases were found to be associated with cumulative occupational exposures to specific agents.
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Enfermedades Cardiovasculares/inducido químicamente , Enfermedades Cardiovasculares/mortalidad , Nitrosaminas/efectos adversos , Enfermedades Profesionales/inducido químicamente , Enfermedades Profesionales/mortalidad , Exposición Profesional/efectos adversos , Enfermedades Respiratorias/inducido químicamente , Enfermedades Respiratorias/mortalidad , Goma/efectos adversos , Adulto , Enfermedad Crónica/mortalidad , Polvo/análisis , Monitoreo del Ambiente/métodos , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Neoplasias , Nitrosaminas/análisis , Exposición Profesional/análisis , Factores de Riesgo , Goma/análisis , Análisis de Supervivencia , Reino Unido/epidemiologíaRESUMEN
Children can get affected by polycyclic aromatic hydrocarbons (PAHs) while they interact with play area soil/rubber surfacing and exposed to PAHs by dermal contact, inhalation and hand-to-mouth activity. A comparative study has been conducted on PAHs profiling and probable cancer risk of children from PAHs present in uncovered playground surface soil and poured rubber surfaced playground dust. Surface soil and dust samples have been collected from 14 different children parks around the Korea University campus, Seoul, Republic of Korea. Concentrations of 16 PAHs in the soils/dust were found to be in a range of 2.82-57.93 µg g-1. Profiling of the PAHs from the playground soils/dust reveals 3-ring PAHs are dominating with 79.9% of total PAHs content, on an average. The diagnostic ratio analysis confirms that vehicular exhaust and fossil fuel burning are likely the main sources of high molecular weight carcinogenic PAHs, whereas low molecular weight PAHs have pyrogenic origin. The probabilistic health risk assessment using Monte Carlo simulations for the estimation of the 95% cancer risk exposed to the PAHs from the surfaced playgrounds shows a little higher value than the USEPA safety standard (1.3 × 10-5). Sensitivity analysis revealed exposure duration and relative skin adherence factor for soil as the most influential parameters of the assessment. Noticeably, cancer risk is approximately 10 times higher in poured rubber surfaced playgrounds than in uncovered soil playgrounds.
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Parques Recreativos , Hidrocarburos Policíclicos Aromáticos/análisis , Goma/análisis , Suelo/química , Niño , Polvo/análisis , Monitoreo del Ambiente/métodos , Humanos , Método de Montecarlo , Neoplasias/epidemiología , Medición de Riesgo , Seúl , Contaminantes del Suelo/análisis , Emisiones de Vehículos/análisisRESUMEN
Worldwide, waste raised from tires counts 1.3-1.5 billion tonnes/year and by the end of 2025, is expected to be more than 2.5 billion tonnes. On 2013, the EU countries reached 3.6 million tonnes of used tires. However, the cheapest treatment method since now is landfilling and is considered to be a major threat for the environment and the public health. In Cyprus, the total tires that were imported on 2015 was 835,142 pieces (5.8% more than the 2014), which were equal to 9638 t, while at the same time, the total waste from those tires were 6629 tonnes. Moreover, the cement industry used 6691 tonnes of tires as alternative fuel. Until now, there are three management systems in place in Cyprus, for the end-of-life tires (ELTs). The collection of ELTs on 2011 was 1817 tonnes while at the end of 2016 was 7201 tonnes. The main treatment methods in Cyprus are the use of ELTs as alternative fuel in cement industry or to produce rubber granules (609-2738 tonnes/year) to be used to construct artificial surfaces or substrate for artificial lawn grounds and limited to pyrolysis (324-837 tonnes/year). At the same time, the environmental fees for the collection of tires varies and depends on the tire category. Furthermore, the market share of ELTs is up to 1.5 million and the total recovery index from the market is closed to 90% the last 6 years (2013-2017). This paper evaluates and assess the existing tire waste management system (TWMS) in Cyprus in order to promote strength and weakness as well as to propose a holistic management system in insular communities in order to adopt the targets set by the concept of circular economy. The SWOT analysis identified as the main weaknesses the absence from the legislation of specific target for the recovery index of tires and the absence of any centralized logistic system to control the existing management systems while the main threats includes bureaucracy and the absence of technical and economic data which will guarantee the financial viability of a centralized treatment unit.
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Goma/análisis , Administración de Residuos/economía , Materiales de Construcción , ChipreRESUMEN
This paper qualifies, quantifies and localizes seafloor marine debris (SMD) in the Moroccan portion of the Mediterranean Sea. Six scientific trawl surveys were conducted by the Moroccan Institute of Fisheries Research from 2012 to 2015 between Cape Spartel (5°W) and Saidia (2°W), during which a total of 497â¯kg of SMD has been collected. Statistical analysis show that the mean abundance differed between surveys, generally ranging from 26 ± 68 to 80 ± 133â¯kg/km2. A typology of SMD indicates that plastic represented 73% of the debris collected, followed by rubber (12%), textile (8%), metal (3%), glass (0.32%), and some unidentified materials (2.70%). Analysis of results shows that the abundance and the distribution of SMD were strongly influenced by the local anthropogenic activities and by rivers inputs. The movements and accumulations in the open sea were also shown to be influenced by the geomorphology and the hydrodynamics of the basin.
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Monitoreo del Ambiente/métodos , Sedimentos Geológicos/química , Plásticos/análisis , Agua de Mar/química , Residuos Sólidos/análisis , Contaminantes Químicos del Agua/análisis , Vidrio/análisis , Mar Mediterráneo , Metales/análisis , Marruecos , Ríos/química , Goma/análisis , Análisis Espacial , Textiles/análisisRESUMEN
The overall world consumption rate of rubber tends to increase by an average of 2.8% per year in the period between 2017 and 2025. Rubber residues represent a severe problem to both health and environment due to their cross-linked structure that offers a prolonged degradation rate. A good solution to eliminate this problem is recycling and recovery, aiming at the production of new materials. The tire crumb can be recycled by chemical/biological recovery, where the elastomer is devulcanized, or by physical recovery, where the three-dimensional network is transformed into small fragments. In this study, we investigated the bio-degradation effect caused by Mealworms (the larvae of Tenebrio molitor Linnaeus) on vulcanized SBR-rubber and tire crumb as a desulphurization method. The surface modifications of both rubbers were studied by instrumental techniques: FTIR-ATR, TGA, XRD, and SEM. The cross-linking degree of the rubber was determined via circular condensation method. The obtained results show that the Tenebrio molitor could survive after three weeks of direct contact with SBR-rubber and tire crumb as the only alimentation. There was a declining effect of cross-linking degree by increasing the contact time between the rubbers and larvae. The FTIR results indicate surface/chemical modifications of the rubbers and the SEM results show the free sulfur after it was released in the form of sulfur flower-like. Also, the TGA results highlight a difference in the degrading behavior and residues of the treated and non-treated rubbers. Therefore, the reported results were promising, demonstrating the biodegradation effect caused by the Tenebrio molitor mealworms, highlighting an alternative and natural mean of degrading vulcanized rubber residues.
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Contaminantes Ambientales/análisis , Restauración y Remediación Ambiental/métodos , Reciclaje/métodos , Goma/análisis , Tenebrio/metabolismo , Animales , Biodegradación Ambiental , Larva/crecimiento & desarrollo , Larva/metabolismo , Tenebrio/crecimiento & desarrolloRESUMEN
While the distribution and effects of microplastics (MPs) have been extensively studied in aquatic systems, there exits little information on their occurrence in the terrestrial environment and their potential impacts on human health. In the present study, street dust and suspended dust were collected from the city and county of Asaluyeh, Iran. Samples were characterized by various microscopic techniques (fluorescence, polarized light, SEM) in order to quantify and classify MPs and microrubbers (MRs) in the urban and industrial environments that are potentially ingestible or inhalable by humans. In < 5-mm street dust retrieved from 15 sites, there were an average of 900â¯MPs and 250â¯MRs per 15â¯g of sample, with MPs exhibiting a range of colours and sizes (<100 to >1000⯵m). Most street dust samples were dominated by spherical and film-like particles and MRs largely made up of different sizes of black fragments and fibrous particulates. Airborne dust collected daily over an eight-day period at two locations revealed the ubiquity of fibrous MPs of sizes ranging from about 2⯵m to 100⯵m and an abundance of about 1 per m-3. These samples contained small MR fragments whose precise characteristics were more difficult to define. Based on the median concentrations in street dust, estimates of acute exposure through ingestion are about 5 and 15â¯MPâ¯d-1 and 2 and 7â¯MRâ¯d-1 for construction workers and young children, respectively. Quantities of inhalable particulates were more difficult to define but the potential toxicity of MPs and MRs taken in by this route was evaluated from assays performed using particulates isolated from street dusts in the presence of an artificial lung fluid. Both types of particle exhibited oxidative potential, with MPs displaying consumptions of different antioxidants that were comparable with corresponding values for a reference urban particulate dust but lower than those for London ambient particulate matter. Thus, MPs and MRs contribute towards the health impacts of urban and industrial dusts but their precise roles remain unclear and warrant further study.
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Contaminantes Atmosféricos/análisis , Polvo/análisis , Monitoreo del Ambiente , Material Particulado/análisis , Plásticos/análisis , Goma/análisis , Goma/química , Adulto , Niño , Ciudades , Humanos , Irán , Tamaño de la Partícula , Material Particulado/química , Plásticos/químicaRESUMEN
BACKGROUND: Taraxacum kok-saghyz R. (Tks) is a promising alternative species to Hevea brasiliensis for production of high quality natural rubber (NR). A comparative transcriptome analysis of plants with differential production of NR will contribute to elucidate which genes are involved in the synthesis, regulation and accumulation of this natural polymer and could help to develop Tks into a rubber crop. RESULTS: We measured rubber content in the latex of 90 individual Tks plants from 9 accessions, observing a high degree of variability. We carried out de novo root transcriptome sequencing, assembly, annotation and comparison of gene expression of plants with the lower (LR plants) and the higher rubber content (HR plants). The transcriptome analysis also included one plant that did not expel latex, in principle depleted of latex transcripts. Moreover, the transcription of some genes well known to play a major role in rubber biosynthesis, was probed by qRT-PCR. Our analysis showed a high modulation of genes involved in the synthesis of NR between LR and HR plants, and evidenced that genes involved in sesquiterpenoids, monoterpenoids and phenylpropanoid biosynthesis are upregulated in LR plants. CONCLUSIONS: Our results show that a higher amount of rubber in the latex in HR plants is positively correlated with high expression levels of a number of genes directly involved in rubber synthesis showing that NR production is highly controlled at transcriptional level. On the other hand, lower amounts of rubber in LR plants is related with higher expression of genes involved in the synthesis of other secondary metabolites that, we hypothesize, may compete towards NR biosynthesis. This dataset represents a fundamental genomic resource for the study of Tks and the comprehension of the synthesis of NR and other biochemically and pharmacologically relevant compounds in the Taraxacum genus.
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Regulación de la Expresión Génica de las Plantas , Goma/metabolismo , Taraxacum/genética , Mapeo Contig , Perfilación de la Expresión Génica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , ARN de Planta/química , ARN de Planta/aislamiento & purificación , ARN de Planta/metabolismo , Goma/análisis , Análisis de Secuencia de ARNRESUMEN
It has been demonstrated that lyophilized drug formulations have an increased propensity to leach substances from the rubber stoppers comprising their primary packaging system when compared to aqueous liquid formulations stored in the same manner. Unfortunately, patient exposure to leachables originating in lyophilized drug products is not known. To that end, the goal of this study was to assess patient exposure to these leachables after reconstitution, storage, and administration of the lyophilized drug. To achieve this goal, several leachables present in 2 commercial lyophilized drug products were quantified after contact with polyvinyl chloride and non-polyvinyl chloride medication bags as well as an infusion set for durations of 15 min to 7 days at refrigerated and ambient temperature. The results obtained from this study showed that the bag's material of construction and the drugs formulation did not impact the mass of the leachables administered. Conversely, the mass of each leachable administered to the patient was reduced or eliminated as the contact duration with the intravenous bag and the temperature increased. However, for shorter contact durations, refrigerated storage, and higher molecular weight compounds, the patient would be exposed to a majority of the leachables originating from the vial.
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Contaminación de Medicamentos , Embalaje de Medicamentos , Liofilización , Leucovorina/administración & dosificación , Polímeros/análisis , Complejo Vitamínico B/administración & dosificación , Composición de Medicamentos , Sistemas de Liberación de Medicamentos , Almacenaje de Medicamentos , Humanos , Inyecciones , Leucovorina/análisis , Espectrometría de Masas , Plastificantes/administración & dosificación , Plastificantes/análisis , Polímeros/administración & dosificación , Goma/administración & dosificación , Goma/análisis , Temperatura , Complejo Vitamínico B/análisisRESUMEN
The risk among asphalt workers of developing adverse health effects may increase due to their occupational exposure. One area of special concern arises when rubber granules are mixed into bitumen to enhance asphalt properties. This research characterizes and compares bitumen and rubber bitumen regarding the emissions of and workers' exposure to particulates, polycyclic aromatic hydrocarbons (PAHs) and benzothiazole. A laboratory and a field study were carried out. In the laboratory, two types of bitumen, one with and one without rubber, were heated up to two temperatures (140°C and 160°C). The concentrations and chemical compositions of the emissions were determined. In the field at asphalt work sites, both emissions and worker exposure measurements were performed. The methods applied included direct-reading sampling techniques next to the asphalt work area and personal sampling techniques on asphalt workers. The exposure measurements on asphalt workers for respirable dust, total dust, particle number and mass, and total PAH concentrations showed similar concentrations when both standard and rubber bitumen were used. The asphalt-surfacing machine operators were the workers with the highest observed exposure followed by the screed operators and roller drivers. Both laboratory and field measurements showed higher concentrations of benzothiazole when rubber bitumen was used, up to 7.5 times higher in the laboratory. The levels of naphthalene, benzo(a)pyrene, and total particles were lower for both types compared with the Swedish occupational exposure limits, 8-h time weighted average concentrations. Benzo(a)pyrene exceeded however the health-based guideline value given by the WHO for both types of bitumen. The study concludes that several air pollutants such as benzothiazole and PAHs are emitted into the air during asphalt work, but it is not evident if exposure to rubber bitumen possesses a higher risk than exposure to standard bitumen in terms of asphalt worker exposure.
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Contaminantes Ocupacionales del Aire/análisis , Monitoreo del Ambiente/métodos , Hidrocarburos/análisis , Exposición Profesional/análisis , Goma/análisis , Benzotiazoles/análisis , Polvo , Humanos , Hidrocarburos/química , Exposición por Inhalación/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Goma/químicaRESUMEN
Frozen-state storage and cold-chain transport are key operations in the development and commercialization of biopharmaceuticals. Today, several marketed drug products are stored (and/or shipped) under frozen conditions to ensure sufficient stability, particularly for live viral vaccines. When these products are stored in glass vials with stoppers, the elastomer of the stopper needs to be flexible enough to seal the vial at the target's lowest temperature to ensure container closure integrity and thus both sterility and safety of the drug product. The container closure integrity assessment in the frozen state (e.g., -20°C, -80°C) should include container closure integrity (CCI) of the container closure system (CCS) itself, impact of processing (e.g., capping process on CCI), and impact of shipment and movement on CCI in the frozen state. The objective of this work was to evaluate the impact of processing and shipment on CCI of a CCS in the frozen state. The impact on other quality attributes was not investigated. In this light, the ThermCCI method was applied to evaluate the impact of shipping stress and variable capping force on CCI of frozen vials and to evaluate the temperature limits of rubber stoppers. In conclusion, retaining CCI during cold storage is mostly a function of vial-stopper combination, and temperatures below -40°C may pose a risk to the CCI of a frozen drug product. Variable capping force may have an influence on the CCI of a frozen drug product if not appropriately assessed. Regarding the impact of shipment on the CCI of glass vials, no indication was given at room temperature, -20°C, or -75°C when compared with static storage at such temperatures.LAY ABSTRACT: Today, several marketed products are stored (and/or shipped) under frozen conditions to ensure sufficient stability. When these products are stored in glass vials with stoppers, the elastomer of the stopper needs to be flexible enough to seal the vial and ensure container closure integrity and thus both sterility and safety of the drug product. The impact of processing and shipment on the container closure integrity (CCI) of a container closure system (vial, stopper, and flip-off cap) in the frozen state is assessed. A helium-leakage test at low temperature (ThermCCI) was used to evaluate the impact of shipping stress and variable capping force on CCI of frozen vials as well as the temperature limits of rubber stoppers. In conclusion, it was found that retaining CCI during cold storage is mostly a function of vial-stopper combination and that temperatures below -40°C may pose a risk to the CCI of a frozen drug product. Variable capping force may have an influence on the CCI of a frozen drug product if not appropriately assessed. Additionally, it was observed that the shipment of the frozen glass vials did not affect the CCI.
Asunto(s)
Embalaje de Medicamentos/normas , Almacenaje de Medicamentos/métodos , Tecnología Farmacéutica/métodos , Embalaje de Medicamentos/instrumentación , Elastómeros/análisis , Congelación , Refrigeración , Goma/análisis , Temperatura , Transportes/métodosRESUMEN
Chlorinated paraffins (CPs) are widely used in domestic polymeric products as plasticizers and fire retardants. In this study, concentrations and congener profiles of short-chain and medium-chain chlorinated paraffins (SCCPs and MCCPs) were investigated in domestic polymeric products, including plastics, rubber and food packaging in China. The average concentrations of SCCPs in polyethylene terephthalate (PET), polypropylene (PP), polyethylene (PE) and food packaging were 234, 3968, 150 and 188â¯ng/g, respectively and the corresponding average concentrations of MCCPs in these samples were 37.4, 2537, 208 and 644â¯ng/g, respectively. The concentrations of CPs in rubber and polyvinylchloride (PVC) were significantly higher than in other matrices. The highest concentrations of SCCPs and MCCPs were found in a PVC cable sheath with 191â¯mg/g and 145â¯mg/g, respectively. Congener group profiles analysis indicated C11- and C13-congener groups were predominant in carbon homologues of SCCPs, and C14-congener groups were predominant in MCCPs. High levels of SCCPs and MCCPs in domestic polymeric products implied that they might be a significant source to the environment and human exposure.
Asunto(s)
Monitoreo del Ambiente , Sustancias Peligrosas/análisis , Parafina/análisis , China , Embalaje de Alimentos/estadística & datos numéricos , Humanos , Hidrocarburos Clorados/análisis , Plásticos/análisis , Bifenilos Policlorados/análisis , Goma/análisisRESUMEN
BACKGROUND: Flames from burning scrap tyres are used in de-furring animals for human consumption in most parts of Nigeria. Emissions from tyres are known to contain a myriad of toxic mixtures especially particulate matter (PM), volatile organic compounds, hazardous air pollutants, and inspirable metals, some of which are known human carcinogens. This cross-sectional study investigated the deleterious health effects of these emissions in occupationally-exposed workers at the Dei-Dei Abattoir, Abuja, Nigeria. METHODS: A total of 156 respondents were divided into two groups. Group 1 (124 butchers) and group 2 [32 administrative staff (AS)]. Data from digital spirometry were used to determine the association between chronic exposure to tyre emissions and lung function. Urinary 1-Hydroxypyrene concentration, phenolic compounds levels and heavy metal concentrations were determined. Also ambient PM and polycyclic aromatic hydrocarbons (PAHs) concentrations at 3 delineated points in the abattoir were measured. FINDINGS: Spirometry results showed significant deterioration of lung function in the butchers. The concentration of 1-Hydroxypyrene (µg/molCret) in the post-shift urine samples of the butchers was significantly higher (P < 0.05) in butchers relative to the AS (0.52 ± 0.13 Vs 0.20 ± 0.07, respectively). Similarly the concentrations of zinc and nickel (mg/l) were significantly higher in the butchers compared to the AS (zinc: 0.91 ± 0.19 Vs 0.31 ± 0.28, respectively; nickel: 0.11 ± 0.06 Vs 0.06 ± 0.02, respectively). Anthracene, fluoranthene, pyrene, benzo-a- pyrene, and PM concentrations were significantly higher at the de-furring point when compared to the wash bay and the administrative building, especially between 8.00 and 8.30 am. CONCLUSION: Occupational exposure to scrap tyre emissions resulted in significant adverse health effects. The existing laws banning the use of burning tyres in meat processing should be enforced while the use of personal protective equipment should be encouraged in abattoirs.
Asunto(s)
Contaminantes Ocupacionales del Aire/toxicidad , Enfermedades Pulmonares/inducido químicamente , Industria para Empaquetado de Carne , Enfermedades Profesionales/inducido químicamente , Exposición Profesional/efectos adversos , Goma/toxicidad , Humo/efectos adversos , Adolescente , Adulto , Contaminantes Ocupacionales del Aire/análisis , Estudios de Casos y Controles , Niño , Estudios Transversales , Femenino , Incendios , Humanos , Enfermedades Pulmonares/diagnóstico , Enfermedades Pulmonares/epidemiología , Masculino , Persona de Mediana Edad , Nigeria/epidemiología , Enfermedades Profesionales/diagnóstico , Enfermedades Profesionales/epidemiología , Exposición Profesional/análisis , Exposición Profesional/estadística & datos numéricos , Material Particulado/análisis , Material Particulado/toxicidad , Goma/análisis , Adulto JovenRESUMEN
Marine debris pollution is considered as a worldwide problem and a direct threat to the environment, economy and human health. In this paper, we provide the first quantitative assessment of debris on the seafloor of the southern part of the economic exclusive waters of Morocco. The data were collected in a scientific trawl survey carried out from 5 to 25 October 2014 between (26N) to (21N) covering different stratums of depths (from 10 to 266m) and following a sampling network of 100 stations distributed randomly in the study area. A total of 603kg of debris was collected and sorted into five main categories: plastic, metal, rubber, textiles and glass. Over 50% of collected items was made by plastic, 94% of them are the plastic fishing gear used to capture the Octopus vulgaris. The analysis of the distribution shows that anthropogenic debris is present in the majority of the prospected area (â¼ 47,541km2) with different densities ranging from 0 to 1768 (± 298,15)kg/km2. The spatial autocorrelation approach using GIS shows that the concentration of this debris is correlated very well with a set of factors such as the proximity to fishing activity sites. Moreover, the mechanism of transportation and dispersion was influenced by the hydrodynamic properties of the region.