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2.
Environ Monit Assess ; 193(8): 478, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34235624

RESUMO

Nanotechnology, in general, and nanomaterials in particular, have conferred and are continuing to confer many benefits to mankind, just as the advent of "plastics" did in previous generations. In the case of carbon nanotubes, which can be produced in vast quantities, documented methods to manage this carbon nanotube waste by recycling and or safe disposal are so minimal that it is a matter of great concern that the paucity of studies on managing carbon nanotube waste may lead to complacency. The latter could be a trigger for human illnesses, through poor handling of carbon nanotube waste. The present study investigated ways to manage recycling and disposal of waste carbon nanotubes and a limited study of some aspects of the toxicity of waste carbon nanotubes in the environment. An eclectic approach was adopted for this study, involving an application and analysis of questionnaires, to ascertain the current practices used by practitioners in carbon nanotube research, as well as experimental work to determine the potential toxicity of carbon nanotubes. This investigation was undertaken to determine if a change from current practice is warranted in the light of the potential toxicity of carbon nanotubes (CNTs). Analysis of the questionnaires revealed the use of differing practices for the recycling and disposal of engineered nanomaterials (ENMs), implying that there is a dire need for a uniform code of practice. The toxicity study showed that carbon nanotubes did not kill earthworms in soil. However, worms were observed to be highly sensitive to increased concentrations of carbon nanotubes. The leaching in a soil column test showed that the movement of carbon nanotubes was inhibited, being confined mainly to the topmost layers of the soil. This is taken to imply that the water table is safe from possible contamination by CNTs.


Assuntos
Nanoestruturas , Nanotubos de Carbono , Monitoramento Ambiental , Plásticos , Reciclagem
3.
Rev Infirm ; 70(272): 28-29, 2021.
Artigo em Francês | MEDLINE | ID: mdl-34238493

RESUMO

At the Pitié-Salpêtrière hospital group (AP-HP, Paris), the central operating room teams embarked, in 2017, on a project to reduce the ecological impact of the procedures performed there. The results are convincing: reduction of the carbon footprint of anesthetic gases, reduction of waste and improvement of its sorting, recycling of metals. The project has spread to the other operating rooms in the hospital group, with strong support from professionals.


Assuntos
Aquecimento Global , Salas Cirúrgicas , Pegada de Carbono , Humanos , Paris , Reciclagem
4.
Chemosphere ; 279: 130862, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34134434

RESUMO

Lead (Pb) entering the body through different channels can damage the function of intestinal mucosal barrier and cause the body stressful inflammatory response to enhance. This study conducted a cross-sectional study to investigate the effects of Pb exposure on intestinal permeability in children by measuring the level of bacterial endotoxin and index of inflammatory cell types in peripheral blood. From November to December 2018, we recruited 187 participants aged 3-6 years by stratified randomization, from an electronic-waste-exposed group (n = 82) and a referent group (n = 105). General demographic information, past history of the digestive system in child, and family situation were informed by children's guardians with questionnaires. Children in the exposed group showed lower weight, height, and body mass index while more diarrhea in a month. Blood Pb and plasma endotoxin were elevated in exposed children than referent children and the positive relationship between them was shown in all children [B (95% CI): 0.072 (0.008, 0.137), P = 0.033]. Peripheral monocyte counts and leukotriene B4 (LTB4) levels were significantly increased in the exposed group. Endotoxin levels were positively correlated with neutrophils, monocytes, and LTB4 [B (95% CI): 0.054 (0.015, 0.093), 0.018 (0.005, 0.031), and 0.049 (0.011, 0.087), respectively, P < 0.05]. To sum up, the exposed children showed lower physical growth levels, poorer gut health, and increased intestinal permeability, which was related to high blood Pb and peripheral inflammatory indices. These results suggest the possible adverse impact of environmental Pb exposure on the intestinal health of children.


Assuntos
Resíduo Eletrônico , Criança , Estudos Transversais , Resíduo Eletrônico/análise , Endotoxinas/toxicidade , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Humanos , Chumbo/toxicidade , Permeabilidade , Reciclagem
5.
Environ Sci Technol ; 55(13): 9339-9351, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34154322

RESUMO

A variety of chemical substances used in plastic production may be released throughout the entire life cycle of the plastic, posing risks to human health, the environment, and recycling systems. Only a limited number of these substances have been widely studied. We systematically investigate plastic monomers, additives, and processing aids on the global market based on a review of 63 industrial, scientific, and regulatory data sources. In total, we identify more than 10'000 relevant substances and categorize them based on substance types, use patterns, and hazard classifications wherever possible. Over 2'400 substances are identified as substances of potential concern as they meet one or more of the persistence, bioaccumulation, and toxicity criteria in the European Union. Many of these substances are hardly studied according to SciFinder (266 substances), are not adequately regulated in many parts of the world (1'327 substances), or are even approved for use in food-contact plastics in some jurisdictions (901 substances). Substantial information gaps exist in the public domain, particularly on substance properties and use patterns. To transition to a sustainable circular plastic economy that avoids the use of hazardous chemicals, concerted efforts by all stakeholders are needed, starting by increasing information accessibility.


Assuntos
Plásticos , Reciclagem , União Europeia , Substâncias Perigosas , Humanos
6.
BMC Psychol ; 9(1): 92, 2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34082817

RESUMO

BACKGROUND: Plastic waste management is one of the most challenging problems of our time. Until now, only 9% of the produced plastics has been recycled. In order to increase recycling, a behavior change towards sorting of plastic waste is needed. Therefore, the main aim of the study is to gain insight in the individual and situational determinants associated with plastic waste sorting behavior. The Integrated Framework for Encouraging Pro-environmental Behaviour will be used as the theoretical framework. This framework assumes that individual egoistic and hedonic values are negatively related to pro-environmental behaviour, whereas individual biospheric and altruistic values are positively related to pro-environmental behaviour. Situational cues can activate these values, resulting in (non) pro-environmental behaviour. Taking the Integrated Framework for Encouraging Pro-environmental Behaviour into account, this study will test the hypothesized associations between individual and situational determinants and plastic waste sorting behavior, using an ecological momentary assessment approach (Experience Sampling Method, ESM). METHODS: A signal-contingent scheme with semi-random intervals will be used for the ESM questionnaire. Over a period of seven consecutive days, an ESM-based smartphone app will prompt participants ten times a day to fill in a short questionnaire containing questions about situational determinants and plastic waste sorting behaviour. Participants will also complete an online questionnaire before and after the study measuring the individual determinants and plastic waste sorting behaviour. DISCUSSION: ESM has many benefits over traditional surveys, such as improved ecological validity and the possibility to explore temporal relationships. The disadvantages of ESM are mainly related to the burden for the participants and the possibility of reactivity effects. The results will provide insight into the relationship between situational cues, individual values and plastic waste behaviour. The practical implications of the findings of this study can be of interest for policy makers in order to reach plastic waste reduction targets. Furthermore, the situational cues that activate values, which increase or decrease plastic waste sorting, can be targeted in interventions. The results of this study can also be relevant for further research studying and stimulating pro-environmental behaviour in general.


Assuntos
Avaliação Momentânea Ecológica , Gerenciamento de Resíduos , Humanos , Plásticos , Reciclagem , Inquéritos e Questionários
7.
Waste Manag ; 130: 117-126, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34082397

RESUMO

Polyethylene terephthalate (PET) is widely used in textile fiber, film, and bottles. Although PET bottle recycling has made great progress, other PET waste is still not recycled. Gasification could be an option for recycling or recovering energy and chemicals from PET waste. However, single stream PET steam gasification in fluidized bed is seldom investigated. In this paper, individual PET gasification experiments were then conducted in a lab-scale bubbling fluidized bed to investigate how gasifying agents, temperature, residence time and steam/fuel ratio affect the product composition. The results showed that, in steam gasification, steam was the main source of H2, but increasing the steam to fuel ratio cannot increase the H2 yield remarkably. Temperature was an essential parameter. Increasing temperature from 750 to 800 °C improved the yields of H2 (+87.7%), the dominant gas product CO2 (+40.3%), and biphenyl (+123%) notably. In contrast to other common thermoplastics, high concentrations of CO2 and biphenyl are the prominent characteristics of PET steam gasification. In addition, plastic steam gasification optimizations for syngas applications were discussed.


Assuntos
Polietilenotereftalatos , Vapor , Biomassa , Gases , Plásticos , Reciclagem
8.
Food Chem ; 360: 130062, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34082377

RESUMO

Epsilon-polylysine (EPL) is a cationic polymer with broad antibacterial activity. Base on this property, anionic carrageenan (CG) was self-assembled with EPL and introduced into the one-pot coprecipitation process to fabricate the magnetic Fe3O4-CG-EPL composites. To demonstrate the successful synthesis of composites, characterization techniques including XRD, FT-IR, TEM, XPS and VSM were employed. The prepared composites exhibited effective antibacterial activity against Alicyclobacillus acidoterrestris with the minimum inhibitory concentration of 10.0 mg mL-1. Investigations into deciphering the antibacterial mechanism demonstrated that the presence of Fe3O4-CG-EPL caused irreversible damage to the cell membrane and serious leakage of intracellular protein, resulting in the inactivation of bacteria. The aim of this work is to develop a new effective control method for A. acidoterrestris in food field.


Assuntos
Antibacterianos/síntese química , Carragenina/química , Óxido Ferroso-Férrico/química , Magnetismo , Polilisina/química , Alicyclobacillus/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Contaminação de Alimentos/prevenção & controle , Sucos de Frutas e Vegetais/microbiologia , Células HEK293 , Humanos , Testes de Sensibilidade Microbiana , Reciclagem
9.
Chemosphere ; 280: 130905, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34162103

RESUMO

Indium recovery from spent liquid crystal displays (LCDs) of monitors was studied by using microwave pyrolysis as a pretreatment step prior to hydrometallurgical processes including acid leaching, solvent extraction, and stripping. After microwave pyrolysis at 150 W for a processing time of 50 min, the hydrometallurgical processes were carried out to sequentially solubilize and increase the purity of indium ions in the product solution. The leaching efficiency of indium was approximately 98% when using 0.5 M of sulfuric acid at a solid-to-liquid ratio (S/L) of 0.1 g/mL. Afterwards, the indium ions in the leachate were extracted by using 20% di(2-ethylhexyl)phosphoric acid (D2EHPA) in kerosene. The purity of indium ions in the organic phase was approximately 87% at an oil-to-aqueous ratio (O/A) of 1/10. Finally, the indium ions in the extract were stripped by using 6 M of hydrochloric acid at an O/A ratio of 10/1. The purity of indium ions in the aqueous phase was as high as 99.98%. The final recovery rate of indium from spent LCDs was approximately 75%, substantially higher than those that were obtained by using shredding or grinding pretreatment. The maximum processing capacity of microwave pyrolysis of spent LCDs could be approximately 500 g, which means that it would only need 0.5 kWh of electricity for the microwave pyrolysis of 1 kg of spent LCDs. According to the experimental results and advantages, it can be concluded that microwave pyrolysis is an effective technique for the pretreatment of spent LCDs.


Assuntos
Índio , Cristais Líquidos , Micro-Ondas , Pirólise , Reciclagem
10.
Nature ; 595(7865): 7, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34188219
11.
Environ Sci Technol ; 55(11): 7643-7653, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33983726

RESUMO

Recovering valuable materials from spent lithium-ion batteries is an important task because of the asymmetry in resource distribution, supply, and demand around the world. A lithium-ion battery is a combination system of various elements and their oxides. Current recovering technologies focus on the separation of valuable metal elements. They can inescapably bring secondary contamination and cost to the environment due to the addition of leachants and precipitants. To recover valuable materials, in situ recombination of elements in spent lithium-ion batteries can be a more economical and environment-friendly solution. Herein, we developed a technology based on in situ aluminothermic reduction and interstitial solid solution transformation to recover high-value γ-LiAlO2 and LiAl5O8 under vacuum and high-temperature (1723 K) conditions. It was found that the process of Li2O filling into the lattice of O-Al-O structure is an energy-reducing process, while LiAl5O8 was an existing high-energy transition-state matter. Since there was no wastewater generated, the process brought a new environment-friendly method for recovering valuable metals from spent lithium-ion batteries. This study also provides new comprehension regarding the design for high-value products' recovery from multi-element mixed wastes on an atomic scale.


Assuntos
Lítio , Reciclagem , Fontes de Energia Elétrica , Metais , Recombinação Genética
12.
Environ Sci Technol ; 55(11): 7186-7207, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34003007

RESUMO

Large quantities of mismanaged plastic waste threaten the health and wellbeing of billions worldwide, particularly in low- and middle-income countries where waste management capacity is being outstripped by increasing levels of consumption and plastic waste generation. One of the main self-management strategies adopted by 2 billion people who have no waste collection service, is to burn their discarded plastic in open, uncontrolled fires. While this strategy provides many benefits, including mass and volume reduction, it is a form of plastic pollution that results in the release of chemical substances and particles that may pose serious risks to public health and the environment. We followed adapted PRISMA guidelines to select and review 20 publications that provide evidence on potential harm to human health from open burning plastic waste, arranging evidence into eight groups of substance emissions: brominated flame retardants; phthalates; potentially toxic elements; dioxins and related compounds; bisphenol A; particulate matter; and polycyclic aromatic hydrocarbons. We semiquantitatively assessed 18 hazard-pathway-receptor combination scenarios to provide an indication of the relative harm of these emissions so that they could be ranked, compared and considered in future research agenda. This assessment overwhelmingly indicated a high risk of harm to waste pickers, a large group of 11 million informal entrepreneurs who work closely with waste, delivering a circular economy but often without protective equipment or a structured, safe system of work. Though the risk to human health from open burning emissions is high, this remains a substantially under-researched topic.


Assuntos
Retardadores de Chama , Eliminação de Resíduos , Humanos , Plásticos , Saúde Pública , Reciclagem
13.
Environ Sci Technol ; 55(12): 8309-8317, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34029063

RESUMO

Lead-acid batteries are a reliable and cost-effective uninterrupted power supply for cars, wheelchairs, and others. Recycling the spent lead-acid batteries has increased cost and could be a serious pollution issue after extensive use. It is important to exploit new-generation application to increase their value. In this article, we used a simple method for recycling spent lead-acid batteries for a useful lead iodide resource with a high purity of over 99% and a recycling yield of 93.1% and then fabricated multifunctional FAPbI3 perovskite diodes using recycled lead iodide (PbI2). The cost of recycled PbI2 based on lab-grade chemicals is estimated to be only 13.6% that of lab-grade PbI2, which undoubtedly greatly reduces the preparation cost of devices in the lab. The external quantum efficiencies of our perovskite diodes prepared with commercial and recycled PbI2 are 19.0 and 18.7%, respectively, which shows that the performance of the device prepared from recycled PbI2 is comparable to that of commercial lab-grade PbI2. Based on the expense of industrial-grade chemicals, the cost of recycled PbI2 is extrapolated to be 70.2% that of industrial-grade PbI2. Therefore, it can not only offer an approach to recycle hazardous solid waste but also save manufacturing cost of new-generation photoelectric devices, leading to earning additional value for lead waste.


Assuntos
Compostos de Cálcio , Fontes de Energia Elétrica , Óxidos , Reciclagem , Titânio
14.
Waste Manag Res ; 39(5): 629-630, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33957824
16.
Chemosphere ; 280: 130677, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33964762

RESUMO

There is growing evidence that e-waste recyclers may be exposed to potentially high levels of metals though associations between such exposures and specific work activities is not well established. In addition, studies have focused on metals traditionally biomonitored and there is no data on the exposure of recyclers to elements increasingly being used in new technologies. In the current study, levels of metals were measured in blood and urine of e-waste recyclers at Agbogbloshie (Ghana) and a control group. Blood and urine samples (from 100 e-waste recyclers and 51 controls) were analyzed for 17 elements (Ag, As, Ba, Cd, Ce, Cr, Eu, La, Mn, Nd, Ni, Pb, Rb, Sr, Tb, Tl, Y) using the ICP-MS. Most e-waste recyclers reported performing at least 4 different tasks in decreasing order as e-waste dismantling (54%), trading/selling of e-waste (45%), burning wires only (40%), and collecting wires after burning (34%). Mean levels of blood Pb, Sr, Tl, and urinary Pb, Eu, La, Tb, and Tl were significantly higher in recyclers versus controls. In general, the collectors and sorters tended to have higher elemental levels than other work groups. Blood Pb levels (mean 92.4 µg/L) exceeded the U.S. CDC reference level in 84% of the e-waste recyclers. Likewise, blood Cd, Mn, and urinary As levels in recyclers and controls were higher than in reference populations elsewhere. E-waste recyclers are exposed to metals traditionally studied (e.g., Pb, Cd, As) and several other technology-critical and rare earth elements which previously have not been characterized through human biomonitoring.


Assuntos
Resíduo Eletrônico , Monitoramento Biológico , Resíduo Eletrônico/análise , Monitoramento Ambiental , Gana , Humanos , Metais/análise , Reciclagem
17.
J Environ Manage ; 292: 112712, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33991826

RESUMO

This study deals with the highly significant and cost-effective pretreatment of the high concentration of the Total Ammonia Nitrogen (TAN) in coking wastewater to improve the biodegradability. Struvite crystallization is a promising process for TAN removal, but the high operating cost hinders its application. To solve this problem, a novel struvite recycling process was proposed for pre-treating TAN present in the coking wastewater, within which struvite was decomposed in the solid-liquid system using Ca(OH)2 as the decomposer. The results indicates that 91% of ammonium in struvite could be stripped out from the decomposition solution, with Ca(OH)2:NH4+ in the molar ratio of 2:1, temperature at 35 °C and a gas to liquid volume ratio of 3500. The resulting solution, post the escape of the ammonia, was dissolved by sulfuric acid. Approximately 100% of the phosphate and magnesium were observed to be released from the insoluble phosphate compounds, resulting in the formation of high-purity gypsum. A TAN removal efficiency of 89% could be achieved by reusing the supernatant after the dissolution of the decomposition product, at pH 9.5 and the Mg:TAN:PO4-P molar ratio of 1.2:1:1. The pilot-scale test demonstrated that approximately 86% TAN was removed from the coking wastewater and the purity of recovered could reach over 99%. Further economic analysis proves that the operation cost of the proposed process is 0.55$ per m3 of coking wastewater, showing a 73% cost reduction when compared to struvite crystallization without recycling.


Assuntos
Coque , Águas Residuárias , Amônia , Hidróxido de Cálcio , Sulfato de Cálcio , Desnitrificação , Compostos de Magnésio , Nitrogênio , Fosfatos , Reciclagem , Estruvita
18.
J Environ Manage ; 292: 112741, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34015615

RESUMO

A long-term feasibility analysis of a 100 ton per day mechanical biological treatment (MBT) plant for municipal solid waste (MSW) valorization and material and energy recovery was carried out. It involves the material recovery and segregation stage (MRSS), organic extraction (pulping), thermophilic anaerobic digestion (AD), composting, effluent treatment plant (ETP), and biogas genset stages producing: 11.90% recyclables, 33% refused derived fuel (RDF), 5% compost of total waste received, 70 m3/day recyclable water and 0.435 MWh/day electricity. The biogas and methane yield were 0.535 and 0.350 m3/kg VSadded (avg.), respectively, with 40% VS removal (avg total solids (TS) 10%). Less than 3% (inert) of total waste received was subjected to landfill disposal. The MBT plant's revenue generation is 995 US$ per day/148 tons ($ 6.72/ton) waste processed. The gross OPEX is 24 US$/ton making the net OPEX of 17 US$/ton (minus revenue), which could be considered as the excellent OPEX for MSW based MBT plants as per global benchmarks. Further, local usage of RDF can significantly reduce the OPEX to 14 US$/ton, as almost 16% of the OPEX goes towards RDF disposal to cement companies located at a distance of 200-500 km from the MBT plant site. As per LCA study, the total GHG emissions have been calculated to be -25.68 tons CO2 eq./100 tons MSW. The negative emissions result from the export of electricity, compost, and RDF as well as recycling of paper and plastic products. Our study presents a cutting-edge scenario of all-inclusive recycling, recovery, and reuse loop of MSW direly required for accomplishing a circular economy.


Assuntos
Eliminação de Resíduos , Resíduos Sólidos , Índia , Reciclagem , Resíduos Sólidos/análise , Instalações de Eliminação de Resíduos
19.
Waste Manag ; 129: 54-61, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34023803

RESUMO

This research examined solid waste management on First Nations communities in western Canada to provide information and insight into programs, practices, policies, and activities, as well as to help bridge an identified gap related to these in the literature. Utilizing a qualitative case study approach, we examined twelve First Nations communities in Canada's western provinces, which relative to other communities, had 'advanced' solid waste management systems in place. Interviews conducted in each of the communities yielded information on six themes grounded in the data, including solid waste facilities and infrastructure, solid waste programs, local capacity, provincial stewardship programs, regulation and enforcement, and funding/finance. Our analysis show that majority of the communities examined are advancing their waste management systems and now have infrastructure/facilities, such as transfer stations and recycling depots, and have implemented recycling programs, which they previously did not have. As well, we learned that implementing such programs has reduced practices, such as open dumping, which the literature highlights as a common way of managing waste in First Nations communities. Most of the communities attributed the success of their programs to regular residential curbside pickups, ability to transport waste out of the community, and community involvement and interest in programs. Despite these improvements, inadequate funding hampers the efforts of communities to sustain and/or expand their programs and maintain facilities. Additionally, most communities face challenges partnering with provincial stewardship programs, and some communities are not clear whether they even qualify to participate in these programs.


Assuntos
Resíduos Sólidos , Gerenciamento de Resíduos , Canadá , Reciclagem
20.
Waste Manag ; 129: 85-94, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34044320

RESUMO

Regenerating cathode material from spent lithium-ion batteries (LIBs) permits an effective approach to resolve resource shortage and environmental pollution in the increasing battery industry. Directly renovating the spent cathode materials is a promising way, but it is still challenging to efficiently remove all of the complex impurities (such as binder, carbon black, graphite and current collectors) without destroying the material structure in the electrode. Herein, a facile strategy to directly remove these impurities and simultaneously repair the degraded LiCoO2 by a target healing method is reported. Specifically, by using an optimized molten salt system of LiOH-KOH (molar ratio of 3:7) where LiNO3 and O2 both serve as oxidants, the impurities can be completely removed, while the structure, composition and morphology of degraded LiCoO2 can be successfully repaired to commercial level based on a two-stage heating process (300 °C for 8 h and 500 °C for 16 h, respectively), resulting in a high recovery rate of approximately 100% for cathode material. More importantly, the regenerated LiCoO2 exhibits a high reversible capacity, good cycling stability and excellent rate capability, which are comparable with commercial LiCoO2. This work demonstrates an efficient approach to recycle and reuse advanced energy materials.


Assuntos
Fontes de Energia Elétrica , Lítio , Eletrodos , Íons , Reciclagem
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