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The incorporation of bactericidal properties into textiles is a widely sought-after aspect, and silver nanoparticles (AgNPs) can be used for this. Here, we evaluate a strategy for incorporating AgNPs into a cotton fabric. For this purpose, a bactericidal textile coating based on a composite of AgNPs and kappa-carrageenan (k-CA) was proposed. The composite was obtained by heating the silver precursor (AgNO3) directly in k-CA solution for green synthesis and in situ AgNPs stabilization. Cotton substrates were added to the heated composite solution for surface impregnation and hydrogel film formation after cooling. Direct synthesis of AgNPs on a fabric was also tested. The results showed that the application of a coating based on k-CA/AgNPs composite can achieve more than twice the silver loading on the fabric surface compared to the textile subjected to direct AgNPs incorporation. Furthermore, silver release tests in water showed that higher Ag+ levels were reached for k-CA/AgNPs-coated cotton. Therefore, inoculation tests with the bacteria Staphylococcus aureus (SA) using the agar diffusion method showed that samples covered with the composite resulted in significantly larger inhibition halos. This indicated that the use of the composite as a coating for cotton fabric improved its bactericidal activity against SA.

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A novel modification technique employing a layer-by-layer (LbL) self-assembly method, integrated with a pressure-assisted filtration system, was developed for enhancing a commercial polyethersulfone (PES) microfiltration (MF) membrane. This modification involved the incorporation of tannic acid (TA) in conjunction with graphene oxide (GO) nanosheets. The effectiveness of the LbL method was confirmed through comprehensive characterization analyses, including ATR-FTIR, SEM, water contact angle (WCA), and mean pore size measurements, comparing the modified membrane with the original commercial one. Sixteen variations of PES MF membranes were superficially modified using a three-factorial design, with the deposited amount of TA and GO as key factors. The influence of these factors on the morphology and performance of the membranes was systematically investigated, focusing on parameters such as pure water permeability (PWP), blue corazol (BC) dye removal efficiency, and flux recovery rate (FRR). The membranes produced with the maximum amount of GO (0.1 mg, 0.55 wt%) and TA as the inner and outer layers demonstrated remarkable FRR and significant BC removal, exceeding 80%. Notably, there was no significant difference observed when using either 0.2 (1.11 wt%) or 0.4 mg (2.22 wt%) in the first layer, as indicated by the Tukey mean test. Furthermore, the modified membrane designated as MF/TA0.4GO0.1TA0.4 was evaluated in the filtration of a simulated dye bath wastewater, exhibiting a BC removal efficiency of 49.20% and a salt removal efficiency of 27.74%. In conclusion, the novel PES MF membrane modification proposed in this study effectively enhances the key properties of pressure-driven separation processes.

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Water and several chemicals, including dyestuffs, surfactants, acids, and salts, are required during textile dyeing processes. Surfactants are harmful to the aquatic environment and induce several negative biological effects in exposed biota. In this context, the present study aimed to assess acute effects of five surfactants, comprising anionic and nonionic classes, and other auxiliary products used in fiber dyeing processes to aquatic organisms Vibrio fischeri (bacteria) and Daphnia similis (cladocerans). The toxicities of binary surfactant mixtures containing the anionic surfactant dodecylbenzene sulfonate + nonionic fatty alcohol ethoxylate and dodecylbenzene sulfonate + nonionic alkylene oxide were also evaluated. Nonionic surfactants were more toxic than anionic compounds for both organisms. Acute nonionic toxicity ranged from 1.3 mg/L (fatty alcohol ethoxylate surfactant) to 2.6 mg/L (ethoxylate surfactant) for V. fischeri and from 1.9 mg/L (alkylene oxide surfactant) to 12.5 mg/L (alkyl aryl ethoxylated and aromatic sulfonate surfactant) for D. similis, while the anionic dodecylbenzene sulfonate EC50s were determined as 66.2 mg/L and 19.7 mg/L, respectively. Both mixtures were very toxic for the exposed organisms: the EC50 average in the anionic + fatty alcohol ethoxylate mixture was of 1.0 mg/L ± 0.11 for V. fischeri and 4.09 mg/L ± 0.69 for D. similis. While the anionic + alkylene oxide mixture, EC50 of 3.34 mg/L for D. similis and 3.60 mg/L for V. fischeri. These toxicity data suggested that the concentration addition was the best model to explain the action that is more likely to occur for mixture for the dodecylbenzene sulfonate and alkylene oxide mixtures in both organisms. Our findings also suggest that textile wastewater surfactants may interact and produce different responses in aquatic organisms, such as synergism and antagonism. Ecotoxicological assays provide relevant information concerning hazardous pollutants, which may then be adequately treated and suitably managed to reduce toxic loads, associated to suitable management plans.

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Azo dyes, widely used in the textile industry, contribute to effluents with significant organic content. Therefore, the aim of this work was to synthesize cobalt ferrite (CoFe2O4) using the combustion method and assess its efficacy in degrading the azo dye Direct Red 80 (DR80). TEM showed a spherical structure with an average size of 33 ± 12 nm. Selected area electron diffraction and XRD confirmed the presence of characteristic crystalline planes specific to CoFe2O4. The amount of Co and Fe metals were determined by ICP-OES, indicating an n(Fe)/n(Co) ratio of 2.02. FTIR exhibited distinct bands corresponding to Co-O (455 cm-1) and Fe-O (523 cm-1) bonds. Raman spectroscopy detected peaks associated with octahedral and tetrahedral sites. For the first time, the material was applied to degrade DR80 in an aqueous system, with the addition of persulfate. Consistently, within 60 min, these trials achieved nearly 100% removal of DR80, even after the material had undergone five cycles of reuse. The pseudo-second-order model was found to be the most fitting model for the experimental data (k2 = 0.07007 L mg-1 min-1). The results strongly suggest that degradation primarily occurred via superoxide radicals and singlet oxygen. Furthermore, the presence of UV light considerably accelerated the degradation process (k2 = 1.54093 L mg-1 min-1). The material was applied in a synthetic effluent containing various ions, and its performance consistently approached 100% in the photo-Fenton system. Finally, two degradation byproducts were identified through HPLC-MS/MS analysis.

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Microorganisms that inhabit the cold Antarctic environment can produce ligninolytic enzymes potentially useful in bioremediation. Our study focused on characterizing Antarctic bacteria and fungi from marine sediment samples of King George and Deception Islands, maritime Antarctica, potentially affected by hydrocarbon influence, able to produce enzymes for use in bioremediation processes in environments impacted with petroleum derivatives. A total of 168 microorganism isolates were obtained: 56 from sediments of King George Island and 112 from Deception Island. Among them, five bacterial isolates were tolerant to cell growth in the presence of diesel oil and gasoline and seven fungal were able to discolor RBBR dye. In addition, 16 isolates (15 bacterial and one fungal) displayed enzymatic emulsifying activities. Two isolates were characterized taxonomically by showing better biotechnological results. Psychrobacter sp. BAD17 and Cladosporium sp. FAR18 showed pyrene tolerance (cell growth of 0.03 g mL-1 and 0.2 g mL-1) and laccase enzymatic activity (0.006 UL-1 and 0.10 UL-1), respectively. Our results indicate that bacteria and fungi living in sediments under potential effect of hydrocarbon pollution may represent a promising alternative to bioremediate cold environments contaminated with polluting compounds derived from petroleum such as polycyclic aromatic hydrocarbons and dyes.

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Abstract Indian major carps are the widely consumed fish species of Pakistan, being a cheap source of proteins and unsaturated fatty acids, they are good for cardiovascular health. Water pollution due to discharge of untreated industrial waste water into water bodies contaminates this precious source of nutrients. The present study therefore, was aimed to assess deterioration of fatty acid profile of three Indian major carp species due to different concentrations of industrial wastes. The water samples were collected from the river Chenab at the site where it receives industrial wastewater via Chakbandi drain. After exposure to 1.5%, 3.0%, and 4.5% dilutions of collected water in different aquaria it was observed that proportion of unsaturated fatty acids in selected fish species were decreased significantly as the intensity of the dose increased (P 0.05). Conversely the level of saturated fatty acids increased with the increasing dose of treatment (P 0.05). These findings suggest that untreated wastewater not only deteriorate the fatty acid profile of aquatic animals but also these toxic substances can reach human body through fish meat and pose further health hazards. Therefore, it is highly recommended that industrial effluents should be treated before they are dumped into water bodies.

Resumo As carpas indianas são as espécies de peixes mais consumidas no Paquistão, sendo uma fonte barata de proteínas e de ácidos graxos insaturados e boa para a saúde cardiovascular. A poluição da água por causa do descarte de resíduos industriais não tratados em corpos dágua contamina essa preciosa fonte de nutrientes. Portanto, o presente estudo teve como objetivo avaliar a deterioração do perfil de ácidos graxos de três principais espécies de carpas indianas em diferentes concentrações de resíduos industriais. As amostras de água foram coletadas do rio Chenab no local onde recebe esgoto industrial via dreno de Chakbandi. Após a exposição a diluições de 1,5%, 3% e 4,5% da água coletada em diferentes aquários, foi observado que a proporção de ácidos graxos insaturados em espécies de peixes selecionadas diminuiu significativamente com o aumento da intensidade da dose (P 0,05). Por outro lado, o nível de ácidos graxos saturados aumentou com a elevação da dose de tratamento (P 0,05). Essas descobertas sugerem que águas residuais não tratadas não apenas deterioram o perfil de ácidos graxos dos animais aquáticos, mas também essas substâncias tóxicas podem atingir o corpo humano por meio da carne de peixe e representar mais riscos à saúde. Portanto, é recomendável que os efluentes industriais sejam tratados antes de serem despejados em corpos dágua.

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Abstract Indian major carps are the widely consumed fish species of Pakistan, being a cheap source of proteins and unsaturated fatty acids, they are good for cardiovascular health. Water pollution due to discharge of untreated industrial waste water into water bodies contaminates this precious source of nutrients. The present study therefore, was aimed to assess deterioration of fatty acid profile of three Indian major carp species due to different concentrations of industrial wastes. The water samples were collected from the river Chenab at the site where it receives industrial wastewater via Chakbandi drain. After exposure to 1.5%, 3.0%, and 4.5% dilutions of collected water in different aquaria it was observed that proportion of unsaturated fatty acids in selected fish species were decreased significantly as the intensity of the dose increased (P < 0.05). Conversely the level of saturated fatty acids increased with the increasing dose of treatment (P < 0.05). These findings suggest that untreated wastewater not only deteriorate the fatty acid profile of aquatic animals but also these toxic substances can reach human body through fish meat and pose further health hazards. Therefore, it is highly recommended that industrial effluents should be treated before they are dumped into water bodies.

Resumo As carpas indianas são as espécies de peixes mais consumidas no Paquistão, sendo uma fonte barata de proteínas e de ácidos graxos insaturados e boa para a saúde cardiovascular. A poluição da água por causa do descarte de resíduos industriais não tratados em corpos d'água contamina essa preciosa fonte de nutrientes. Portanto, o presente estudo teve como objetivo avaliar a deterioração do perfil de ácidos graxos de três principais espécies de carpas indianas em diferentes concentrações de resíduos industriais. As amostras de água foram coletadas do rio Chenab no local onde recebe esgoto industrial via dreno de Chakbandi. Após a exposição a diluições de 1,5%, 3% e 4,5% da água coletada em diferentes aquários, foi observado que a proporção de ácidos graxos insaturados em espécies de peixes selecionadas diminuiu significativamente com o aumento da intensidade da dose (P < 0,05). Por outro lado, o nível de ácidos graxos saturados aumentou com a elevação da dose de tratamento (P < 0,05). Essas descobertas sugerem que águas residuais não tratadas não apenas deterioram o perfil de ácidos graxos dos animais aquáticos, mas também essas substâncias tóxicas podem atingir o corpo humano por meio da carne de peixe e representar mais riscos à saúde. Portanto, é recomendável que os efluentes industriais sejam tratados antes de serem despejados em corpos d'água.

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Textile wastewater (TWW) is one of the most hazardous wastewaters for ecosystems when it is discharged directly into water streams without adequate treatment. Some organic pollutants, such as dyes in TWW, are considered refractory compounds that are difficult to degrade using conventional chemical and biological methods. The bicarbonate-activated peroxide (BAP) system is an advanced oxidation process (AOP) based on applying H2O2, which has been demonstrated to be a clean and efficient technology for dye degradation, with the advantage of operating under slightly alkaline pH conditions. In this study, response surface methodology (RSM) based on a central composite design (CCD) was used to optimize the degradation of TWW contaminated with the azo dye Acid Black 194 using the BAP system catalyzed with cobalt ions in solution (Co2+). The analysis of variance (ANOVA) technique was applied to identify significant variables and their individual and interactive effects on the degradation of TWW. The optimum reagent concentrations for degrading TWW at 25 °C and with 45 µM Co2+ were 787.61 and 183.34 mM for H2O2 and NaHCO3, respectively. Under these conditions, complete decolorization (≥99.40), 32.20 % mineralization, and 52.02 % chemical oxygen demand removal were achieved. Additionally, the acute toxicity of textile wastewater before and after oxidation was evaluated with guppy fish (Poecilia reticulata), showing a total reduction in mortality after treatment with the Co2+-BAP system. The Co2+-BAP oxidation system is a potential method for textile wastewater treatment, which, in addition to achieving complete decolorization and partial mineralization, improves biodegradability and reduces the toxicity of the treated water.

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In this work, it is presented a first approach of a mathematical and kinetic analysis for improving the decoloration and further degradation process of an azo dye named acid red 27 (AR27), by means of a novel microbial consortium formed by the fungus Trametes versicolor and the bacterium Pseudomonas putida. A multivariate analysis was carried out by simulating scenarios with different operating conditions and developing a specific mathematical model based on kinetic equations describing all stages of the biological process, from microbial growth and substrate consuming to decoloration and degradation of intermediate compounds. Additionally, a sensitivity analysis was performed by using a factorial design and the Response Surface Method (RSM), for determining individual and interactive effects of variables like, initial glucose concentration, initial dye concentration and the moment in time for bacterial inoculation, on response variables assessed in terms of the minimum time for: full decoloration of AR27 (R1 = 2.375 days); maximum production of aromatic metabolites (R2 = 1.575 days); and full depletion of aromatic metabolites (R3 = 12.9 days). Using RSM the following conditions improved the biological process, being: an initial glucose concentration of 20 g l-1, an initial AR27 concentration of 0.2 g l-1 and an inoculation moment in time of P. putida at day 1. The mathematical model is a feasible tool for describing AR27 decoloration and its further degradation by the microbial consortium of T. versicolor and P. putida, this model will also work as a mathematical basis for designing novel bio-reaction systems than can operate with the same principle of the described consortium.

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Polyamide fabrics were dyed with concentrations ranging from 4% to 0.25% (o.w.f.) of the natural dye, potassium norbixinate (annatto). The exhaustion, chromatic coordinates, colouristic intensity (K/S), and fastness to washing and rubbing were evaluated. The natural dye was characterised, and its maximum absorption peaks were identified at 452 nm and 482 nm through UV-vis scanning. Its main chemical groups were identified by FTIR-ATR. All dyeings exhibited high exhaustion percentage, with a maximum of 98.4% for 1% dye concentration. The dyed samples displayed visually appealing orange hues, with a maximum K/S value of 6.9. Most of the fastness test results were rated between 5 and 4/5, remaining within the standards established by most textile industries. Potassium norbixinate exhibited a similar tinctorial behaviour to synthetic acid dyes for polyamide, suggesting ionic chemical reaction interaction between dye and polyamide, highlighting the potential use in the textile industry.

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Denim, also known as jeans, is a fabric made up of braided cotton threads dyed indigo blue, whose fibers contain approximately 10% of non-cellulosic impurities that reduce its commercial value. Microbial enzymes can act in the cleaning and desizing processes of jeans, improving their color, softness, and covering capacity. The recombinant Xylanase II (XynA2) from the aquatic bacterial Caulobacter crescentus (C. crescentus), previously characterized in terms of its biochemical features, was applied to the biotreatment of jeans to clean and degum it. The biotreatment performance was evaluated in terms of tissue weight loss, amount of reducing sugars released and analysis of the images obtained by scanning electron microscopy (SEM). Biotreated tissues, at 12 and 24 h, showed a dry weight loss of 4.9 and 6.6%, respectively. The reducing sugars amount released after XynA2 action over the jean's fibers showed statistically significant values when compared with each other and with their respective controls. SEM images clearly shown that the fabric treated for 12 h presented a smooth and polished surface, while the fabric treated for 24 h showed the cotton fibers broken, displaying severe damage to the textile. The best treatment for the jeans was in the presence of 1 U mg-1 XynA2 at pH 8 and 60 °C during 12 h. In conclusion, XynA2 of C. crescentus was satisfactorily applied for the biopolishing of denim jeans being a more sustainable alternative to the use of chemical and abrasive processes to obtain the same effects.

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Waste derived from the textile industry can contain a wide variety of pollutants of organic and inorganic natures, such as dyes (e.g., acid, basic, reactive, mordant dyes) and toxic metals (e.g., lead, chromium, cadmium). The presence of pollutants at high concentrations in textile waste makes them relevant sources of pollution in the environment. To solve this problem, various technologies have been developed for the removal of pollutants from these matrices. Thus, adsorption emerges as an efficient alternative for textile waste remediation, providing advantages as simplicity of operation, economy, possibility of using different adsorbent materials, and developing on-line systems that allow the reuse of the adsorbent during several adsorption/desorption cycles. This review will initially propose an introduction to the adsorption world, its fundamentals, and aspects related to kinetics, equilibrium, and thermodynamics. The possible mechanisms through which a pollutant can be retained on an adsorbent will be explained. The analytical techniques that offer valuable information to characterize the solid phases as well as each adsorbate/adsorbent system will be also commented. The most common synthesis techniques to obtain carbon nano-adsorbents have been also presented. In addition, the latest advances about the use of these adsorbents for the removal of pollutants from textile waste will be presented and discussed. The contributions reported in this manuscript demonstrated the use of highly efficient carbon-based nano-adsorbents for the removal of both organic and inorganic pollutants, reaching removal percentages from 65 to 100%.

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The textile industry is known for its large consumption of water, energy, and chemical products, making it one of the most environmentally impactful activities. To measure these environmental impacts, life cycle analysis (LCA) is a powerful tool that considers the entire process, from the extraction of raw materials to the finalization of textile products. In this context, this work aimed to present a systematic study on the use of the LCA methodology in the environmental assessment of effluents from the textile industry. The survey for data was carried out using the Scopus and Web of Science databases, and the PRISMA method was utilized for organizing and selecting of articles. During the meta-analysis phase bibliometric and specific data were extracted from selected publications. For the bibliometric analysis, a quali-quantitative approach was adopted, and the VOSviewer software was employed. The review encompasses a total of 29 articles, which were published between 1996 and 2023.The majority of the reviewed articles have shown the use of the LCA as a supportive tool for optimization focusing on sustainability, comparing the environmental, economic, and technical aspects through different approaches. The findings revel that China has the highest number of authors among the selected articles, while researchers from France and Italy had the highest number of international collaborations. The ReCiPe and CML methods were the most frequently used for evaluating life cycle inventories, with global warming, terrestrial acidification, ecotoxicity, and ozone depletion being the main impact categories. The use of activated carbon in textile effluents treatment has shown to be promising since it is environmentally friendly.

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Background: Conotoxins exhibit great potential as neuropharmacology tools and therapeutic candidates due to their high affinity and specificity for ion channels, neurotransmitter receptors or transporters. The traditional methods to discover new conotoxins are peptide purification from the crude venom or gene amplification from the venom duct. Methods: In this study, a novel O1 superfamily conotoxin Tx6.7 was directly cloned from the genomic DNA of Conus textile using primers corresponding to the conserved intronic sequence and 3' UTR elements. The mature peptide of Tx6.7 (DCHERWDWCPASLLGVIYCCEGLICFIAFCI) was synthesized by solid-phase chemical synthesis and confirmed by mass spectrometry. Results: Patch clamp experiments on rat DRG neurons showed that Tx6.7 inhibited peak calcium currents by 59.29 ± 2.34% and peak potassium currents by 22.33 ± 7.81%. In addition, patch clamp on the ion channel subtypes showed that 10 µM Tx6.7 inhibited 56.61 ± 3.20% of the hCaV1.2 currents, 24.67 ± 0.91% of the hCaV2.2 currents and 7.30 ± 3.38% of the hNaV1.8 currents. Tx6.7 had no significant toxicity to ND7/23 cells and increased the pain threshold from 0.5 to 4 hours in the mouse hot plate assay. Conclusion: Our results suggested that direct cloning of conotoxin sequences from the genomic DNA of cone snails would be an alternative approach to obtaining novel conotoxins. Tx6.7 could be used as a probe tool for ion channel research or a therapeutic candidate for novel drug development.

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This paper describes the development of a coating for cotton and polypropylene (PP) fabrics based on a polymeric matrix embedded with cuprous oxide nanoparticles (Cu2O@SDS NPs) in order to inactivate SARS-CoV-2 and manufactured by a simple process using a dip-assisted layer-by-layer technology, at low curing temperature and without the need for expensive equipment, capable of achieving disinfection rates of up to 99%. The polymeric bilayer coating makes the surface of the fabrics hydrophilic, enabling the transportation of the virus-infected droplets to achieve the rapid inactivation of SARS-CoV-2 by contact with the Cu2O@SDS NPs incorporated in the coated fabrics.

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Conventional textile effluent treatments cannot remove methylene blue, a mutagenic azo dye, and an endocrine disruptor, that remains in the drinking water after conventional water treatment. However, the spent substrate from Lentinus crinitus mushroom cultivation, a waste, could be an attractive alternative to remove persistent azo dyes in water. The objective of this study was to assess the methylene blue biosorption by spent substrate from L. crinitus mushroom cultivation. The spent substrate obtained after mushroom cultivation had been characterized by the point of zero charge, functional groups, thermogravimetric analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. Moreover, the spent substrate biosorption capacity was determined in function of pH, time, and temperature. The spent substrate had a point of zero charge value of 4.3 and biosorbed 99% of methylene blue in pH from 3 to 9, with the highest biosorption in the kinetic assay of 15.92 mg g- 1, and in the isothermal assay of 120.31 mg g- 1. Biosorption reached equilibrium at 40 min after mixing and best fitted the pseudo-second-order model. Freundlich model best fitted the isothermal parameters and each 100 g spent substrate biosorbed 12 g dye in an aqueous solution. The spent substrate of L. crinitus cultivation is an effective biosorbent of methylene blue and an alternative to removing this dye from water, adding value to the mushroom production chain, and supporting the circular economy.

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The European Union has identified the Textile and Clothing industry as one of the essential objectives towards carbon neutrality in 2050 in line with the "European Green Deal". There are no previous research papers focused on analysing the drivers and inhibitors of the past greenhouse gas emission changes of the textile and clothing industry in Europe. This paper aims to analyse the determinants of the changes in these emissions, and the disassociation level between emissions and economic growth, throughout the 27 Member States of the European Union, from 2008 to 2018. A Logarithmic Mean Divisia Index that explains the key drivers of the changes in greenhouse gas emissions of European Union Textile and Cloth industry and a Decoupling Index have been applied. The results generally conclude that the intensity and carbonisation effects are key factors that contribute to reducing greenhouse gas emissions. The lower relative weight of the textile and clothing industry throughout the EU-27 was noteworthy, and favours lower emissions, partially counteracted by the activity effect. Also, most Member States have been decoupling the industry's emissions from economic growth. Our policy recommendation shows that if further reductions in greenhouse gas emissions are to be achieved, energy efficiency improvements and cleaner use of energy sources would offset the potential increase in emissions of this industry as a result of a relative increase in its gross value added.

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The use of recycled waste has been the focus of several studies due to its potential to allow a more sustainable use of construction materials and minimize improper waste disposal in landfills or incinerators. More specifically, garment textile waste has been examined as internal reinforcement of cementitious matrices to increase the deformability and control fissure formation. In this study, polyester textiles are analyzed and incorporated in cementitious composites in order to evaluate their mechanical properties. Results show that significant improvements in mechanical properties of composites are obtained depending on the impregnation treatment applied to the textile waste. In the direct tensile stress test, the waste impregnation with styrene butadiene polymer plus silica fume improved 35.95% in the weft direction and 9.33% in the warp direction. Maximum stress increased 53.57% and 64.48% for composites with styrene-butadiene rubber impregnation and styrene-butadiene rubber plus silica fume impregnation, respectively, when compared to the unreinforced composite. The flexural tensile strength of composites impregnated reinforcements with styrene-butadiene rubber and styrene-butadiene rubber plus silica fume presented increases in strength by 92.10% and 94.73%, respectively, when compared to the unreinforced sample. The impact test confirmed that styrene-butadiene rubber plus silica fume impregnation produced greater tenacity of the composite. In the microstructure, it is confirmed that the impregnated textile reinforcement resulted in composites with greater adhesion between the fabric and the cementitious matrix. Thus, light textile waste is concluded to be a viable construction material for non-structural elements.

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Azo dyes used in textile products contain aromatic amines (AAs), which may be released into the environment after skin bacteria cleavage the azo bond. In Europe, 22 carcinogenic AAs are regulated. Unfortunately, no information is available in many non-European countries, including Brazil. This study aimed to determine the concentrations of 20 regulated AAs in clothes marketed in Brazil and Spain. Generally, higher levels of regulated AAs were found in samples sold in Brazil than in Spain, which is linked to the lack of regulation. Sixteen AAs showed concentrations above 5 mg/kg in samples commercialized in Brazil, while 11 exceeded that threshold in Spain. Regulated AAs with levels above 5 mg/kg were more found in synthetic clothes of pink color. Concentrations in clothing were also used to evaluate the dermal exposure to AAs in 3 vulnerable population groups. The highest exposure corresponded to 2,4-diaminoanisole for toddlers in Brazil and 4,4-oxydianiline for newborns in Spain. Non-cancer risks associated with exposure to 4,4-benzidine by Brazilian toddlers was 14.5 (above the threshold). On the other hand, 3,3-dichlorobenzidine was associated with potential cancer risks for newborns and toddlers in Brazil. Given this topic's importance, we recommend conducting continuous studies to determine the co-occurrence of carcinogenic substances.

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