Highly Stretchable, Biodegradable, and Recyclable Green Electronic Substrates.

As a steady stream of electronic devices being discarded, a vast amount of electronic substrate waste of petroleum-based nondegradable polymers is generated, raising endless concerns about resource depletion and environmental pollution. With coupled reagent (CR)-grafted artificial marble waste (AMW@CR) as functional fillers, polylactic acid (PLA)-based highly stretchable biodegradable green composite (AMW@CR-SBGC) is prepared, with elongation at break up to more than 250%. The degradation mechanism of AMW@CR-SBGC is deeply revealed. AMW@CR not only contributed to the photodegradation of AMW@CR-SBGC but also significantly promoted the water degradation of AMW@CR-SBGC. More importantly, AMW@CR-SBGC showed great potential as sustainable green electronic substrates and AMW@CR-SBGC-based electronic skin can simulate the perception of human skin to strain signals. The outstanding programmable degradability, recyclability, and reusability of AMW@CR-SBGC enabled its application in transient electronics. As the first demonstration of artificial marble waste in electronic substrates, AMW@CR-SBGC killed three birds with one stone in terms of waste resourcing, e-waste reduction, and saving nonrenewable petroleum resources, opening up vast new opportunities for green electronics applications in areas such as health monitoring, artificial intelligence, and security.

Scalable and Consolidated Microbial Platform for Rare Earth Element Leaching and Recovery from Waste Sources.

Chemical methods for the extraction and refinement of technologically critical rare earth elements (REEs) are energy-intensive, hazardous, and environmentally destructive. Current biobased extraction systems rely on extremophilic organisms and generate many of the same detrimental effects as chemical methodologies. The mesophilic methylotrophic bacterium Methylobacterium extorquens AM1 was previously shown to grow using electronic waste by naturally acquiring REEs to power methanol metabolism. Here we show that growth using electronic waste as a sole REE source is scalable up to 10 L with consistent metal yields without the use of harsh acids or high temperatures. The addition of organic acids increases REE leaching in a nonspecific manner. REE-specific bioleaching can be engineered through the overproduction of REE-binding ligands (called lanthanophores) and pyrroloquinoline quinone. REE bioaccumulation increases with the leachate concentration and is highly specific. REEs are stored intracellularly in polyphosphate granules, and genetic engineering to eliminate exopolyphosphatase activity increases metal accumulation, confirming the link between phosphate metabolism and biological REE use. Finally, we report the innate ability of M. extorquens to grow using other complex REE sources, including pulverized smartphones, demonstrating the flexibility and potential for use as a recovery platform for these critical metals.

Designing a sustainable reverse logistics network for used cell phones based on offline and online trading systems.

Unsustainable production and consumption are driving a significant increase in global electronic waste, posing substantial environmental and human health risks. Even in more developed nations, there is the challenge of low collection rates. In response, we integrate offline and online trading systems and design a material efficiency strategy for used cell phones. We propose a new multi-objective optimization framework to maximize profit, carbon emissions reduction, and circularity in the process of recycling and treatment. Considering multi-period, multi-product, multi-echelon features, as well as price sensitive demand, incentives, and qualities, we established a new multi-objective mixed-integer nonlinear programming optimization model. An enhanced, Fast, Non-Dominated Solution Sorting Genetic Algorithm (ASDNSGA-II) is developed for the solution. We used operational data from a leading Chinese Internet platform to validate the proposed optimization framework. The results demonstrate that the reverse logistics network designed achieves a win-win situation regarding profit and carbon emission reduction. This significantly boosts confidence and motivation for engaging in recycling efforts. Online recycling shows robust profitability and carbon reduction capabilities. An effective coordination mechanism for pricing in both online and offline channels should be established, retaining offline methods while gradually transitioning towards online methods. To increase the collection rate, it is essential to jointly implement a transitional strategy, including recycling incentives and subsidy policies. Additionally, elevating customer environmental awareness should be viewed as a long-term strategy, mitigating the cost of increasing collection rates during the market maturity stage (high collection rates).

A Review of the Occurrence and Recovery of Rare Earth Elements from Electronic Waste.

Electronic waste (e-waste) contains valuable rare earth elements (REEs) essential for various high-tech applications, making their recovery crucial for sustainable resource management. This review provides an overview of the occurrence of REEs in e-waste and discusses both conventional and emerging green technologies for their recovery. Conventional methods include physical separation, hydrometallurgy, and pyrometallurgy, while innovative approaches such as bioleaching, supercritical fluid extraction, ionic liquid extraction, and lanmodulin-derived peptides offer improved environmental sustainability and efficiency. The article presents case studies on the extraction of REEs from waste permanent magnets and fluorescent powders, highlighting the specific processes involved. Future research should focus on developing eco-friendly leaching agents, separation materials, and process optimization to enhance the overall sustainability and efficiency of REE recovery from e-waste, addressing both resource recovery and environmental concerns effectively.

Associations of insulin sensitivity and immune inflammatory responses with child blood lead (Pb) and PM2.5 exposure at an e-waste recycling area during the COVID-19 lockdown.

Fine particular matter (PM2.5) and lead (Pb) exposure can induce insulin resistance, elevating the likelihood of diabetes onset. Nonetheless, the underlying mechanism remains ambiguous. Consequently, we assessed the association of PM2.5 and Pb exposure with insulin resistance and inflammation biomarkers in children. A total of 235 children aged 3-7 years in a kindergarten in e-waste recycling areas were enrolled before and during the Corona Virus Disease 2019 (COVID-19) lockdown. Daily PM2.5 data was collected and used to calculate the individual PM2.5 daily exposure dose (DED-PM2.5). Concentrations of whole blood Pb, fasting blood glucose, serum insulin, and high mobility group box 1 (HMGB1) in serum were measured. Compared with that before COVID-19, the COVID-19 lockdown group had lower DED-PM2.5 and blood Pb, higher serum HMGB1, and lower blood glucose and homeostasis model assessment of insulin resistance (HOMA-IR) index. Decreased DED-PM2.5 and blood Pb levels were linked to decreased levels of fasting blood glucose and increased serum HMGB1 in all children. Increased serum HMGB1 levels were linked to reduced levels of blood glucose and HOMA-IR. Due to the implementation of COVID-19 prevention and control measures, e-waste dismantling activities and exposure levels of PM2.5 and Pb declined, which probably reduced the association of PM2.5 and Pb on insulin sensitivity and diabetes risk, but a high level of risk of chronic low-grade inflammation remained. Our findings add new evidence for the associations among PM2.5 and Pb exposure, systemic inflammation and insulin resistance, which could be a possible explanation for diabetes related to environmental exposure.

Environmental impact of metal halide perovskite solar cells and potential mitigation strategies: A critical review.

Metal halide perovskite solar cells (PSCs) have gained extensive attention in the field of solar photovoltaic technology over the past few years. Despite being a remarkable alternative to fossil fuels, solar cells may have detrimental effects on the environment and human health owing to the use of toxic materials during manufacturing. Although modern metal-halide-based PSCs are stable and have encapsulation to prevent the release of potentially toxic materials into the environment, their destruction due to strong winds, hail, snow, landslides, fires, or waste disposal can result in the exposure of these materials to the environment. This may lead to the contamination of soil and groundwater, and uptake of potentially toxic elements by plants, subsequently affecting humans and other living organisms via food chain contamination. Despite worldwide concern, the environmental and ecotoxicological impacts of metal-halide-based PSCs have not been comprehensively surveyed. This review summarizes and critically evaluates the current status of metal-halide-based PSC production and its impact on environmental sustainability, food security, and human health. Furthermore, safe handling and disposal methods for the waste generated from metal-halide-based PSCs are proposed, with a focus on recycling and reuse. Although some studies have suggested that the amount of lead released from metal halide PSCs is far below the maximum permissible levels in most soils, a clear conclusion cannot be reached until real contamination scenarios are assessed under field conditions. Precautions must be taken to minimize environmental contamination throughout the lifecycle of PSCs until nontoxic and similarly performing alternative solar photovoltaic products are developed.

Electrochemically reduced graphene oxide films from Zn-C battery waste for the electrochemical determination of paracetamol and hydroquinone.

Contributing to the development of sustainable electroanalytical chemistry, electrochemically reduced graphene oxide (ERGO) films obtained from residual graphite of discharged Zn-C batteries are proposed in this work. Graphite from the cathode of discarded Zn-C batteries was recovered and used in the synthesis of graphene oxide (GO) by the modified Hummer's method. The quality of the synthesized GO was verified using different characterization methods (FT-IR, XRD, SEM, and TEM). GO films were deposited on a glassy carbon electrode (GCE) by the drop coating method and then electrochemically reduced by cathodic potential scanning using cyclic voltammetry. The electrochemical features of the ERGO films were investigated using the ferricyanide redox probe, as well as paracetamol (PAR) and hydroquinone (HQ) molecules as model analytes. From the cyclic voltammetry assays, enhanced heterogeneous electron transfer rate constants (k0) were observed for all redox systems studied. In analytical terms, the ERGO-based electrode showed higher analytical sensitivity than the bare and GO-modified GCE. Using differential pulse voltammetry, wide linear response ranges and limits of detection of 0.14 µmol L-1 and 0.65 µmol L-1 were achieved for PAR and HQ, respectively. Furthermore, the proposed sensor was successfully applied to the determination of PAR and HQ in synthetic urine and tap water samples (recoveries close to 100%). The outstanding electrochemical and analytical properties of the proposed ERGO films are added to the very low cost of the raw material, being presented as a green-based alternative for the development of electrochemical (bio)sensors with unsophisticated resources.

A sustainable route for the recovery of metals from waste printed circuit boards using methanesulfonic acid.

The rapid increase in electronic waste (e-waste) generation and its unsustainable management pose a threat to the environment and human well-being. However, various valuable metals are present in e-waste, which makes it a potential secondary source to recover metals. Therefore, in the present study, efforts were made to recover valuable metals (Cu, Zn, and Ni) from waste printed circuit boards (WPCB) of computers using methanesulfonic acid (MSA). MSA is contemplated as a biodegradable green solvent and has a high solubility for various metals. The effect of various process parameters (MSA concentration, H2O2 concentration, stirring speed, liquid to solid ratio, time, and temperature) was investigated on metal extraction to optimize the process. At the optimized process conditions, 100% extraction of Cu and Zn was achieved, while Ni extraction was around 90%. The kinetic study for metal extraction was performed using a shrinking core model and findings showed that MSA-aided metal extraction is a diffusion-controlled process. Activation energies were found to be 9.35, 10.89, and 18.86 kJ/mol for Cu, Zn, and Ni extraction, respectively. Furthermore, the individual recovery of Cu and Zn was achieved using the combination of cementation and electrowinning, which resulted in 99.9% purity of Cu and Zn. The current study proposes a sustainable solution for the selective recovery of Cu and Zn from WPCB.

The importance of the pretreatment of samples in Nd quantification from NdFeB magnets through inductively coupled plasma atomic emission spectroscopy (ICP-OES)-a rapid and streamlined methodology.

In this study, we emphasize the critical role of sample pretreatment. We report on the behavior of NdFeB magnet samples exposed to four different acid media for digestion. NdFeB magnets are becoming a significant source of neodymium, a rare-earth element critical to many technologies and a potential substitute for traditional mining of the element. To address this, we meticulously tested nitric acid, hydrochloric acid, acetic acid, and citric acid, all at a concentration of 1.6 M, as economical and environmentally friendly alternatives to the concentrated mineral acids commonly used in the leaching of these materials. The pivotal stage involves the initial characterization of samples in the solid state using SEM-EDX and XPS analysis to obtain their initial composition. Subsequently, the samples are dissolved in the four aforementioned acids. Finally, neodymium is quantified using ICP-OES. Throughout our investigation, we evaluated some analytical parameters to determine the best candidate for performing the digestion, including time, limits of detection and quantification, accuracy, recovery of spike samples, and robustness. After careful consideration, we unequivocally conclude that 1.6 M nitric acid stands out as the optimal choice for dissolving NdFeB magnet samples, with the pretreatment of the samples being the critical aspect of this report.

A review on management practices, environmental impacts, and human exposure risks related to electrical and electronic waste in Vietnam: findings from case studies in informal e-waste recycling areas.

Electrical and electronic waste (e-waste) has become a global concern, especially in developing countries. In this review, we conducted a literature survey of e-waste management practices, processing activities, and adverse effects in Vietnam, an emerging country in Southeast Asia, by gathering data from peer-reviewed articles published between 2009 and 2021. This is the first review paper to comprehensively discuss management and research aspects regarding e-waste in an Asian developing country. Due to the lack of an effective management and recycling system, a certain portion of Vietnamese e-waste has been processed by informal sectors without appropriate recycling and pollution control technology, resulting in localized contamination and human exposure to toxic chemicals. Primitive processing activities, such as manual dismantling, open burning, and plastic recycling, have been identified as important contributors to the environmental emission and human exposure to toxic elements (notably As, Mn, Ni, Pb, Zn) and organic pollutants like flame retardants, PAHs, PCBs, and dioxin-related compounds. Informal e-waste processing from these small-scale workshops can release pollutants at similar levels compared to large-scale facilities in developed countries. This fact suggests an urgent need to develop management best practices for e-waste in Vietnam as well as other emerging and developing countries, in order to increase recycling efficiency and minimize their adverse impacts on environmental and human health.

Introducing heterotrophic iron ore bacteria as new candidates in promoting the recovery of e-waste strategic metals.

Electrical instruments are an integral part of human life resulting in a vast electronic waste generation (74.7 Mt by 2030), threatening human life and the environment due to its hazardous nature. Therefore, proper e-waste management is a necessity. Currently, bio-metallurgy is a sustainable process and an emerging research field. Simultaneous leaching of metals using two groups of indigenous heterotrophs and autotrophs was an exciting work done in this study. Bioleaching experiments using pre-adapted cultures were investigated at three e-waste densities: 5, 10, and 15 g/L. Statistical analysis was done using two-way ANOVA. Copper (93%), zinc (21.5%), and nickel (10.5%) had the highest recovery efficiencies. There was a significant difference between copper, nickel, tin, and zinc concentrations and the bacterial group (P < 0.05); Iron-oxidizing bacteria showed the most weight decrease and recovered 46-47% of total metals, mainly copper and nickel, while sulfur oxidizers were more capable of zinc leaching. The heterotrophs solubilized tin preferably and substantially decreased e-waste weight. Using heterotrophs alongside autotrophs is proposed to promote metal recovery.

Trace metal load of two urban wetlands with varied catchment activities in Ghana.

This study compared Lead (Pb), Chromium (Cr), Copper (Cu), Zinc (Zn), Mercury (Hg), Arsenic (As) and Cadmium (Cd) concentrations in sediment, water, and biota at Vaughan Dam which receives limited sewage effluent discharge from residential areas, and Korle Lagoon which receives industrial effluents, electronic waste, garages-spill oil and a host of others in addition to residential sewage effluent discharge. Samples were analyzed with Atomic Absorption Spectrometer. The results showed that concentrations of trace metals were generally higher in the sediment, water, and plants from the Korle Lagoon but only Cu in the sediment of Korle Lagoon showed a significantly high concentration. The similarities in the rank orders of the metal concentrations together with the dominance of Zn and Pb in most compartments of the wetlands indicated major differences did not exist in the contaminant input to the two wetlands except electronic waste recycling and disposal that resulted in significantly high copper concentrations in the sediment of Korle Lagoon. No evidence of biomagnification was determined along the food chains of the Vaughan Dam and the Korle Lagoon for all the metals studied.The Tilapia zilli from Vaughan Dam, the only biota that is regularly consumed from the wetlands, had Cr, Cu, Pb, Cd, Hg, and As concentrations above FAO/WHO permissible limits and therefore pose a health risk to consumers.

Waste of electrical and electronic equipment management from the perspective of a circular economy: A Review.

In addition to the difficulties involved in the management of conventional solid waste, the management of waste of electrical and electronic equipment (WEEE) is significantly more complex due to its unusual chemical composition and fast generation. Both developed and developing countries have been looking for solutions to deal with the problems caused by the growing flow of WEEE, especially regarding sustainable solutions based on reducing resource exploitation by the recovery of materials from this type of waste. In this context, this work presents a quali-quantitative and comprehensive literature review of the publications on the management of WEEE, from the perspective of a circular economy. The results showed that the first publications on the topic appear in 2006, with a significant increase from 2015, the year when the Circular Economy Action Plan was instituted in the European Community. The most prominent authors have been giving emphasis to researches on recycling, reuse and technologies for the recovery of materials/energy from WEEE. Nevertheless, few studies have been found focusing on the prevention/reduction in WEEE generation, priority actions of the WEEE management hierarchy. The works analysed show that the current management of WEEE, despite considering the circularity of materials, prioritizes the development of technological solutions of the end-of-pipe type, greatly represented by the recovery of materials, instead of preventing the generation, which may be detrimental to long-term sustainability. The work ends with the presentation of a SWOT-TOWS (strengths, weaknesses, opportunities and threats) analysis conducted to define the main strategies for the improvement of WEEE management from a circular economy perspective.

Effects of leachates from UV-weathered microplastic on the microalgae Scenedesmus vacuolatus.

Plastics undergo successive fragmentation and chemical leaching steps in the environment due to weathering processes such as photo-oxidation. Here, we report the effects of leachates from UV-irradiated microplastics towards the chlorophyte Scenedesmus vacuolatus. The microplastics tested were derived from an additive-containing electronic waste (EW) and a computer keyboard (KB) as well as commercial virgin polymers with low additive content, including polyethylene (PE), polyethylene terephthalate (PET), polypropylene (PP), and polystyrene (PS). Whereas leachates from additive-containing EW and KB induced severe effects, the leachates from virgin PET, PP, and PS did not show substantial adverse effects in our autotrophic test system. Leachates from PE reduced algae biomass, cell growth, and photosynthetic activity. Experimental data were consistent with predicted effect concentrations based on the ionization-corrected liposome/water distribution ratios (Dlip/w) of polymer degradation products of PE (mono- and dicarboxylic acids), indicating that leachates from weathering PE were mainly baseline toxic. This study provides insight into algae toxicity elicited by leachates from UV-weathered microplastics of different origin, complementing the current particle- vs. chemical-focused research towards the toxicity of plastics and their leachates.

Risk of neurodegeneration among residents of electronic waste recycling areas.

The abnormal disposal process of electronic waste (e-waste) always emits a variety of toxic substances that enter the human body through various environmental media and can have many adverse health effects. Metals are thought to be inextricably linked to neurodegeneration. In the present study, we tried to explore the neurodegenerative status of subjects exposed to e-waste and the association between metal intake and neurodegeneration. We recruited the residents near the e-waste recycling area (the exposed group) and the residents without any e-waste contact history (the reference group) for a comparative study with detection and analysis of metals, biomarkers associated with neurodegeneration or oxidative stress (OS). The results showed that the metals between the reference and exposed group were significantly different. The concentrations of Brain-derived neurotrophic factor (BDNF) and ß-amyloid protein 42 (Aß42) in the exposed groups were significantly lower, while the levels of Euchromatic Histone lysine Methyltransferase 1 (EHMT1), Bromodomain Adjacent to Zinc finger domain 2B (BAZ2B) and Malondialdehyde (MDA) were significantly higher than in the reference groups. Although the ratio of Aß42/Aß40 had no statistical significance in the two groups, the medians of the ratio in the exposed group was lower than in the reference group. The linear regression and mediating effect analysis showed that MDA (OS) might mediate the effects of metals on EHMT1(pAg-MDA <0.001, pMDA-EHMT1 <0.05, pAg-EHMT1 <0.001). It could be inferred from the results of the present investigation that e-waste exposure had a high risk of neurodegeneration, especially Sliver (Ag) and Nickel (Ni).

Spatial distribution and ecological risks of polychlorinated biphenyls in a river basin affected by traditional and emerging electronic waste recycling in South China.

With development of e-waste related legislation in China, formal recycling activities are designated in some areas while informal ones are illegally transferred to emerging areas to avoid supervision. However, the resulting environmental impact and ecological risks are not clear. Here, we investigated the discharge of polychlorinated biphenyls (PCBs) to soil and aquatic environments by e-waste recycling activities in the Lian River Basin, China. The study area included a designated industrial park in the traditional e-waste recycling area (Guiyu, known as the world's largest e-waste center), several emerging informal recycling zones, and their surrounding areas and coastal area. A total of 27 PCBs were analyzed, and the highest concentration was found in an emerging site for soil (354 ng g-1) and in a traditional site for sediment (1350 ng g--1) respectively. The pollution levels were significantly higher in both the traditional and emerging recycling areas than in their respective upstream countryside areas (p = 0.0356 and 0.0179, respectively). Source analysis revealed that the traditional and emerging areas had similar PCB sources mainly associated with three PCB technical mixtures manufactured in Japan (KC600) and the USA (Aroclor 1260 and Aroclor 1262). The PCB pollution in their downstream areas including the coastal area was evidently affected by the formal and informal recycling activities through river runoff. The ecological risk assessments showed that PCBs in soils and sediments in the Lian River Basin could cause adverse ecotoxicological consequences to humans and aquatic organisms.

Recovery of Metals from Electronic Waste-Printed Circuit Boards by Ionic Liquids, DESs and Organophosphorous-Based Acid Extraction.

The extraction of metals from waste printed circuit boards (WPCBs) with ionic liquids (ILs), Deep Eutectic Solvents (DESs) and organophosphorous-based acid (Cyanex 272) has been presented. The study was undertaken to assess the effectiveness of the application of the new leaching liquids, and the new method of extraction of metals from the leachate and the solid phase with or without the leaching process. Solvent extraction from the liquid leachate phase has been studied in detail with popular ILs, such as tetraoctylphosphonium bromide, {[P8,8,8,8][Br] and tributyltetradecylphosphonium chloride, [P4,4,4,14][Cl] using Aqueous Biphasic Systems (ABS) method. Trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl) phosphinate, [P6,6,6,14][Cyanex272], ([P6,6,6,14][BTMPP]), trihexyltetradecylphosphonium thiocyanate, [P6,6,6,14][SCN], methyltrioctylammonium chloride (Aliquat 336), as well as bis(2,4,4-trimethylpentyl)phosphinic acid (Cyanex 272) were also used in the extraction of metals from the leachate. Two DESs (1) {choline chloride + lactic acid, 1:2} and (2) {choline chloride + malonic acid, 1:1} were used in the extraction of metals from the solid phase. The extraction behavior of metals with DESs was compared with that performed with three new bi-functional ILs: didecyldimethylammonium salicylate, [N10,10,1,1][Sal], didecyldimethylammonium bis(2-ethylhexyl) phosphate, [N10,10,1,1][D2EHPA], and didecyldimethylammonium bis(2,4,4-trimethylpentyl) phosphinate, [N10,10,1,1][Cyanex272]. The [P6,6,6,14][Cyanex272]/toluene and (Cyanex 272 + diethyl phosphite ester) mixtures exhibited a high extraction efficiency of about 50-90% for different metal ions from the leachate. High extraction efficiency of about 90-100 wt% with the ABS method using the mixture {[P8,8,8,8][Br], or [P4,4,4,14][Cl] + NaCl + H2O2 + post-leaching liquid phase} was obtained. The DES 2 revealed the efficiency of copper extraction, ECu = 15.8 wt% and silver, EAg = 20.1 wt% at pH = 5 from the solid phase after the thermal pre-treatment and acid leaching. The solid phase extraction efficiency after thermal pre-treatment only was (ECu = 9.6 wt% and EAg = 14.2 wt%). The use of new bi-functional ILs did not improve the efficiency of the extraction of metal ions from the solid phase. Process factors such as solvent concentration, extraction additives, stripping and leaching methods, temperature, pH and liquid/solid as well as organic/water ratios were under control. For all the systems, the selectivity and distribution ratios were described. The proposed extraction processes can represent alternative paths in new technologies for recovering metals from electronic secondary waste.

Quantification and characterization of recovered materials in the cycle of the informal household electronic waste dismantling in Buriram province, Thailand: A challenge towards sustainable management and circular economy.

The numerous amount of electronic waste (e-waste) has not been managed effectively resulting informal dismantling sites are being expanded in Thailand. The government attempts to improve the efficiency of an integrated e-waste management system, but baseline data of e-waste stream in informal sectors are insufficient. This research aimed to investigate the inflow and outflow of the materials throughout the informal e-waste dismantling processes at the well-known second-largest community in Buriram province during 2017-2018. To describe the quantities of dismantled materials, a material flow analysis was performed. The overall amount of e-waste taken to the community was estimated to be in the range of 1593-12,943 tonnes year-1. Valuable materials could be recovered at more than 90% (by mass) from fans, refrigerators, washing machines, microwaves and air conditioners. The amount of e-waste residue that the local administrative organization had to handle was up to 1144 tonnes year-1. The quantitative data retrieved from this study could provide a satisfactory equation for estimating the amount of separated valuable and non-valuable materials. Recyclable materials from dismantling have an economic incentive, e-waste dismantlers in a small and large household group that can earn approximately 798 and 1262 USD month-1 income, respectively. The notable e-waste characterization and quantification of recovered materials would be useful for improving the potential circular flow of e-waste in Thailand.

A pathway to involve consumers for exchanging electronic waste: a deep learning integration of structural equation modelling and artificial neural network.

The pandemic of COVID-19 has disrupted every human life by putting the global activities at halt. In such a situation, people while staying at home tend to have an increased consumption which also leads to an increased level of waste generation. The case of electronic waste is also not different; however, it has severe repercussions while comparing it with other general household wastes. The application of reverse logistics by the manufacturers though serve the purpose but its success is highly dependent on the participation of the consumers. Hence, the present study is an attempt to gauge the level of participation of the consumers in the reverse exchange programs. Because of the predictability limitations of the typical Structural-Equation-Modelling models, the present study employs the deep learning of the dual-staged partial least squares-structural equation modelling artificial neural network approach. The findings of the study confirms the individual's attitude as the most significant determinant of the intention to exchange, followed by level of awareness and norms, whereas perceived behavior control was found to be least important though significant. Based on these findings, the manufacturers have been recommended to improve the consumers' involvement in reverse exchange programs, whereas government institutions are also recommended to encourage public-private partnerships in channelizing the product returns.

From inequitable to sustainable e-waste processing for reduction of impact on human health and the environment.

Recycling of electric and electronic waste products (e-waste) which amounted to more than 50 million metric tonnes per year worldwide is a massive and global operation. Unfortunately, an estimated 70-80% of this waste has not been properly managed because the waste went from developed to low-income countries to be dumped into landfills or informally recycled. Such recycling has been carried out either directly on landfill sites or in small, often family-run recycling shops without much regulations or oversights. The process traditionally involved manual dismantling, cleaning with hazardous solvents, burning and melting on open fires, etc., which would generate a variety of toxic substances and exposure/hazards to applicators, family members, proximate residents and the environment. The situation clearly calls for global responsibility to reduce the impact on human health and the environment, especially in developing countries where poor residents have been shouldering the hazardous burden. On the other hand, formal e-waste recycling has been mainly conducted in small scales in industrialized countries. Whether the latter process would impose less risk to populations and environment has not been determined yet. Therefore, the main objectives of this review are: 1. to address current trends and emerging threats of not only informal but also formal e-waste management practices, and 2. to propose adequate measures and interventions. A major recommendation is to conduct independent surveillance of compliance with e-waste trading and processing according to the Basel Ban Amendment. The recycling industry needs to be carefully evaluated by joint effort from international agencies, producing industries and other stakeholders to develop better processes. Subsequent transition to more sustainable and equitable e-waste management solutions should result in more effective use of natural resources, and in prevention of adverse effects on health and the environment.