WEEE Treatment in Developing Countries: Environmental Pollution and Health Consequences-An Overview

Can e-waste recycling provide a solution to the scarcity of rare earth metals? An overview of e-waste recycling methods

Recycling e-waste is seen as a sustainable alternative to compensate for the limited natural rare earth elements (REEs) resources and the difficulty of accessing these resources. Recycling facilitates the recovery of valuable products and minimizes emissions during their transportation. Numerous studies have been reported on e-waste recycling using various techniques, including thermo-, hydro- and biometallurgical approaches. However, each approach still has technical, economic, social, or environmental limitations. This review highlights the potential of recycling e-waste, including outlining the current unutilized potential of REE recycling from different e-waste components. An in-depth analysis of e-waste generation on a global scale and Australian scenario, along with various hazardous impacts on ecosystem and human health, is reported. In addition, a comprehensive summary of various metal recovery processes and their merits and demerits is also presented. Lifecycle analysis for recovering REEs from e-waste indicate a positive environmental impact when compared to REEs produced from virgin sources. In addition, recovering REEs form secondary sources eliminated ca. 1.5 times radioactive waste, as seen in production from primary sources scenario. The review outcome demonstrates the increasing potential of REE recycling to overcome critical challenges, including issues over supply security and localized dependency.

A Critical Review on the Recovery of Base and Critical Elements from Electronic Waste-Contaminated Streams Using Microbial Biotechnology

Pollution by end-of-life electronics is a rapid ever-increasing threat and is a universal concern with production of million metric tons of these wastes per annum. Electronic wastes (E-waste) are rejected electric or electronic equipment which have no other applications. The aggrandized unproper land filling of E-waste may generate hazardous effects on living organisms and ecosystem. At present, millions of tons of E-waste await the advancement of more efficient and worthwhile recycling techniques. Recovery of base and critical elements from electronic scraps will not only reduce the mining of these elements from natural resources but also reduces the contamination caused by the hazardous chemicals (mostly organic micropollutants) released from these wastes when unproperly disposed of. Bioleaching is reported to be the most eco-friendly process for metal recycling from spent electronic goods. A detailed investigation of microbial biodiversity and a molecular understanding of the metabolic pathways of bioleaching microorganisms will play a vital function in extraction of valuable minerals from the end-of-life scraps. Bioleaching technique as an economic and green technology costs around 7 USD per kg for effective reusing of E-waste as compared to other physical and chemical techniques. This review provides a summary of worldwide scenario of electronic pollutants; generation, composition and hazardous components of electronic waste; recycling of valuable elements through bioleaching; mechanism of bioleaching; microorganisms involved in base and critical element recovery from E-waste; commercial bioleaching operations; and upcoming aspects of this eco-friendly technique.

Prenatal Exposure to Heavy Metals and Adverse Birth Outcomes: Evidence From an E-Waste Area in China

Electronic waste that has not been properly treated can lead to environmental contamination including of heavy metals, which can pose risks to human health. Infants, a sensitive group, are highly susceptible to heavy metals exposure. The aim of this study was to investigate the association between prenatal heavy metal exposure and infant birth outcomes in an e-waste recycling area in China. We analyzed cadmium (Cd), chromium (Cr), manganese (Mn), lead (Pb), copper (Cu), and arsenic (As) concentrations in 102 human milk samples collected 4 weeks after delivery. The results showed that 34.3% of participants for Cr, which exceeds the World Health Organization (WHO) guidelines, as well as the mean exposure of Cr exceeded the WHO guidelines. We collected data on the birth weight (BW) and length of infants and analyzed the association between metal concentration in human milk and birth outcomes using multivariable linear regression. We observed a significant negative association between the Cd concentration in maternal milk and BW in female infants (β = -162.72, 95% CI = -303.16, -22.25). In contrast, heavy metals did not associate with birth outcomes in male infants. In this study, we found that 34.3% of participants in an e-waste recycling area had a Cr concentration that exceeded WHO guidelines, and there was a significant negative association between prenatal exposure to the Cd and infant BW in females. These results suggest that prenatal exposure to heavy metals in e-waste recycling areas may lead to adverse birth outcomes, especially for female infants.

Organophosphate esters (OPEs) in a heavily polluted river in South China: Occurrence, spatiotemporal trends, sources, and phase distribution

In the past decade, organophosphate esters (OPEs) undergo rapid increase in production and use. Meanwhile, owing to their additive property, OPEs exhibit liability to escape from related products and therefore ubiquity in various environments. Moreover, numerous researches verify their bioavailability and negative effects on biota and human, hence their occurrence and associated risks have caught much concern, particularly those in aquatic systems. So far, however, OPEs in water are generally investigated as a whole, their phase distribution and behavior in waterbodies are incompletely characterized. We examined 25 OPEs in water (including dissolved and particulate phases), sediment, and sediment core samples from the Lian River, which flows through the Guiyu e-waste recycling zone and Shantou specific economic zone in South China. Compared to most global waterbodies, the Lian River showed high or ultrahigh OPE levels in both water and sediments, particularly in the reaches surrounded by e-waste recycling and plastic-related industries, which were the top two greatest OPE sources. Non-industrial and agriculture-related anthropogenic activities also contributed OPEs. Sediment core data suggested that OPEs have been present in waters in Guiyu since the 1960s and showed a temporal trend consistent with the local waste-recycling business. The phase distribution of OPEs in the Lian River was significantly correlated with their hydrophobicity and solubility. Owing to their wide range of physicochemical properties, OPE congeners showed significant percentage differences in the Lian River water and sediments. Generally, OPEs in water reflect their dynamic real-time inputs, while those in sediment signify their accumulative deposition, which is another cause of their phase distribution disparities in the Lian River. The physicochemical parameters of OPEs first imposed negative and then positive influences on their dissolved phase-sediment distribution, indicating the involvement of both the adsorption of dissolved OPEs and the deposition of particle-bound OPEs.

Soil heavy metal pollution from waste electrical and electronic equipment of repair and junk shops in southern Thailand and their ecological risk

The waste electrical and electronic equipment (WEEE) stream in Thailand shifted from exporting WEEE to recycling them in domestic enterprises after China's import restrictions on e-waste in 2018. This study aims to investigate the pollution status, pollution sources, and ecological risk of heavy metals from manual WEEE dismantling facilities (12 repair shops and 8 junk shops) in the Nakhon Si Thammarat province of southern Thailand by examining the concentrations of As, Cd, Ni, and Pb in the topsoil (0-15 cm) during the wet and dry seasons. The results revealed that the mean concentrations of all heavy metals were higher during the dry season than in the wet season. The concentrations of analyzed soil heavy metals decreased as the intensity of e-waste dismantling activities increased, with recycling sites > repair sites > control sites (no e-waste recycling activities). Only 10% of WEEE processing workshops (junk shops) had soil Pb and As concentrations that exceeded Thailand's residential soil quality standards. However, ecological indexing models based on the geo-accumulation index found that 75% of electric repair shops were contaminated with the analyzed heavy metals, particularly Pb. Moreover, the Nemerow integrated pollution index indicated that 16.7% of electric repair shops were on the pollution warning line. Our findings suggest that policymakers should promote ecological risk assessment as a method for mitigating the negative environmental impact of electronic repair businesses, which are widely dispersed in residential areas and tend to dominate the WEEE stream because of the circular economy concept of "right to repair", and highlight the decline of junk shops and e-waste dismantling villages for waste export resulting from China's ban.

Human health risk associated with metal exposure at Agbogbloshie e-waste site and the surrounding neighbourhood in Accra, Ghana

Agbogbloshie in Accra, Ghana, was a center for informal e-waste recycling until it was closed recently. This study investigated the potential health risks of toxic metals (including As, Cd, Cu, Ni, Pb, Sb, and Zn) found in the surface soils based on their concentrations and in vitro bioaccessibility. Mean concentrations at the burning sites were As: 218; Cd: 65; Cr: 182; Cu: 15,841; Ni: 145; Pb: 6,106; Sb: 552; and Zn: 16,065 mg/kg while the dismantling sites had mean concentrations of As: 23; Cd: 38; Cr: 342; Cu: 3239; Ni: 96; Pb: 681; Sb: 104; and Zn: 1658 mg/kg. The findings confirmed the enrichment of potentially toxic metals at the dismantling and burning sites, exceeding international environmental soil quality guidelines. Based on the total metal concentrations, bioaccessibility, and calculated risk indices, the risks associated with incidental ingestion of soil-borne metal contaminants at the dismantling and burning sites were very high. Despite evidence of higher metal concentrations in the communities near the burning and dismantling sites, the human health risk associated with soil ingestion was significantly lower in the surrounding neighborhood.

Urbanization and residents' health: from the perspective of environmental pollution

The development of urbanization has important implications for the environment and the human health. However, it is still lacking a comprehensive analysis between urbanization, environmental pollution, and residents' health based on a unified research system. In this study, we assessed the integrated level of urbanization by the entropy method based on the representative indicators. It has been found that there is a significant progress in the urbanization level in the provinces from 2005 to 2020. The impact of urbanization development on environmental pollution was analyzed using the system GMM (Generalized Method of Moments), and the results show an inverted U-shaped relationship between urbanization and environmental pollution. Fixed effect regression model analysis infers that urbanization has a dual impact on population health. Urbanization promotes residents' health by improving medical conditions, but the environmental pollution caused by urbanization is harmful to residents' health. This paper integrated urbanization, environmental pollution, and residents' health into a research system to analyze the impact of urbanization on environmental pollution and residents' health. Some policy recommendations have been proposed based on the research results for promoting high-quality development of urbanization, reducing environmental pollution, and improving residents' health.

Electronic waste exposure and DNA damage: a systematic review and meta-analysis

OBJECTIVES

Inappropriate processing and disposal of electronic waste (e-waste) expose workers and surrounding populations to hazardous chemicals, including clastogens and aneugens. Recently, considerable literature has grown around e-waste recycling, associated chemical exposures and intermediate health outcomes, including DNA damage. Micronuclei (MN) frequency has been widely used as a biomarker to investigate DNA damage in human populations exposed to genotoxic agents. We conducted a systematic review of published studies to assess DNA damage in e-waste-exposed populations and performed a meta-analysis to evaluate the association between e-waste exposure and DNA damage.

METHODS

This systematic review with meta-analysis was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement checklist. Articles published in English from January 2000 through December 2020 investigating the associations between e-waste exposure and DNA damage were retrieved from the following three major databases: MEDLINE, ProQuest, and Scopus. Studies that reported the use of MN assay as a biomarker of DNA damage were included for meta-analysis. Studies that also reported other DNA damage biomarkers such as chromosomal aberrations, comet assay biomarkers, 8-hydroxy-2'-deoxyguanosine (8-OHdG), telomere length, apoptosis rate were reported using narrative synthesis.

RESULTS

A total of 20 publications were included in this review, of which seven studies were within the occupational setting, and the remaining 13 studies were ecological studies. The review found six biomarkers of DNA damage (micronuclei, comets assay parameters (tail length, % tail DNA, tail moment, and olive tail moment), 8-OHdG, telomere length, apoptosis rate and chromosomal aberrations) which were assessed using seven different biological matrices (buccal cells, blood, umbilical cord blood, placenta, urine and semen). Most studies showed elevated levels of DNA damage biomarkers among e-waste exposed populations than in control populations. The most commonly used biomarkers were micronuclei frequency (n=9) in peripheral blood lymphocytes or buccal cells and 8-OHdG (n=7) in urine. The results of the meta-analysis showed that electronic waste recycling has contributed to an increased risk of DNA damage measured using MN frequency with a pooled estimate of the standardized mean difference (SMD) of 2.30 (95% CI: 1.36, 3.24, p<0.001) based on 865 participants.

CONCLUSIONS

Taken together, evidence from this systematic review with meta-analysis suggest that occupational and non-occupational exposure to e-waste processing is associated with increased risk of DNA damage measured through MN assay and other types of DNA damage biomarkers. However, more studies from other developing countries in Africa, Latin America, and South Asia are needed to confirm and increase these results' generalizability.

Recovery of gold from e-waste via food waste byproducts

Global materials' and energy constraints and environmental issues call for a holistic approach to waste upcycling. We propose a chemically rational, cost-effective and environmentally friendly recovery of non-leaching gold from e-waste using aqueous chemistry with hydrogen peroxide, an environmentally benign oxidant, and lactic acid, a food chain byproduct. The oxidation of the base metals enables the release of gold in its metallic state in the form of flakes subsequently separated via filtration. Our main byproduct is a precursor of Cu₂O, a relevant metal oxide for solar energy conversion applications. The recovered gold was characterized by scanning electron microscopy, energy dispersive spectroscopy and x-ray photoelectron spectroscopy to gain insight into the morphology of the flakes and their chemical composition. Furthermore, recovered gold was used to successfully fabricate the source and drain electrodes in organic field-effect transistors.

Occupational exposure to metals among battery recyclers in France: Biomonitoring and external dose measurements

In battery-recycling facilities, exposure to trace elements may occur through inhalation of contaminated dust or vapor emanating from the treatment processes. Exposure of battery-recycling workers to lead has been quite well covered in the literature. In contrast, we lack data on exposure to other elements contained in batteries. The aim of this study was to characterize the exposure of French battery recyclers to multiple elements using biomonitoring and airborne measurements. Eighty-six workers participated in the study. Inhalable metal concentrations were determined for personal airborne samples, and total exposure was determined from pre-shift and post-shift urine samples collected during the working week. In both types of sample, a total of 33 trace elements were measured using inductively coupled plasma mass spectrometry. Results showed battery recyclers to be mostly exposed to Cd, Co, Cr, Li, Mn, Ni, and Pb. Administrative and sorting workers were exposed at lower levels than maintenance, treatment, and dismantling workers. Cd, Co, Li, Mn, and Ni were detected at high levels in air samples, especially near the treatment facilities, with airborne cadmium levels of up to 79.4 µg/m³. Urinary sample analysis indicated exposure to Cd and Co, with levels measured at up to 27.6 and 3.34 µg/g of creatinine, respectively. Concentrations were compared to data reported for e-waste recycling companies. The data presented provide valuable information on exposure to trace elements for workers involved in battery-recycling. They also highlight the need to improve both collective and individual protective measures, which were not sufficient in the participating companies.

The role of fingernail selenium in the association between arsenic, lead and mercury and child development in rural Vietnam: a cross-sectional analysis

As, Pb and Hg are common environmental contaminants in low- and middle-income countries. We investigated the association between child toxicant exposure and growth and development and determined if this association was mitigated by Se concentration. Toxicant concentrations in fingernail samples, anthropometry and Bayley's Scales of Infant Development, 3rd edition domains were assessed in 36-month-old children whose mothers had been part of a randomised controlled trial in rural Vietnam. Multivariable regression analyses were performed to estimate the effect of toxicant exposure on clinical outcomes with adjustments for potential confounders and interaction with fingernail Se concentration. We analysed 658 children who had data for at least one physical or developmental outcome, and at least one toxicant measurement, and each of the covariates. Fingernail As concentration was negatively associated with language (estimate per 10 % increase in As: -0·19, 95 % CI: (-0·32, -0·05)). Pb was negatively associated with cognition (estimate per 10 % increase in Pb: -0·08 (-0·15, -0·02)), language (estimate per 10 % increase in Pb: -0·18 (-0·28, -0·10)) and motor skills (estimate per 10 % increase in Pb: -0·12 (-0·24, 0·00)). Hg was negatively associated with cognition (estimate per 10 % increase in Hg: -0·48, (-0·72, -0·23)) and language (estimate per 10 % increase in Hg -0·51, (-0·88, -0·13)) when Se concentration was set at zero in the model. As Se concentration increased, the negative associations between Hg and both cognition and language scores were attenuated. There was no association between toxicant concentration and growth. As, Pb and Hg concentrations in fingernails of 3-year-old children were associated with lower child development scores. The negative association between Hg and neurological development was reduced in magnitude with increasing Se concentration. Se status should be considered when assessing heavy metal toxicants in children and their impact on neurodevelopmental outcomes.

Migration and Transformation of Multiple Heavy Metals in the Soil–Plant System of E-Waste Dismantling Site

E-waste generation has become a major environmental issue worldwide. Heavy metals (HMs) in e-waste can be released during inappropriate recycling processes. While their pollution characteristics have been studied, the migration and transformation of different multi-metal fractions in soil–plant system of e-waste dismantling sites is still unclear. In this study, pot experiments were conducted to investigate the migration and transformation of different multi-metal fractions (Cu, Pb, Zn and Al) in the soil–plant system using two Chinese cabbage cultivars (heavy metals low-accumulated variety of Z1 and non-low-accumulated Z2) treated with or without biochar. The result showed that the acid-soluble fraction of Cu, Pb, Zn and Al in soil decreased by 5.5%, 55.7%, 7.8% and 21.3%, but the residual fraction (ResF) of them increased by 48.5%, 1.8%, 30.9% and 43.1%, respectively, when treated with biochar and plants, compared to that of the blank soil (CK). In addition, Pb mainly existed as a reducible fraction, whereas Cu existed as an oxidisable fraction. Biochar combined with plants significantly increased the ResF of multi-metals, which reduced the migration ability of Pb among all other metals. The relative amount of labelled ¹³C in the soil of Z1 was higher than that of Z2 (25.4 fold); among them, the Gram-negative bacteria (18-1ω9c, 18-1ω7c) and fungi (18-2ω6c) were significantly labelled in the Z1-treated soil, and have high correlation with HM migration and transformation. In addition, Gemmatimonadete were significantly positive in the acid-soluble fraction of HMs, whereas Ascomycota mostly contributed to the immobilisation of HMs. Therefore, the distribution of fractions rather than the heavy metal type plays an important role in the HM migration in the soil–plant system of e-waste dismantling sites.

New Models to Reduce the Health Risks of Informal WEEE Recyclers in MTN Phone Village, Rumukurushi, Port Harcourt, Nigeria

Waste electrical and electronic equipment (WEEE) management in Port Harcourt, an oil-producing city in Nigeria, has become an environmental challenge for the location. WEEE recycling is predominantly managed by informal recyclers, who lack the skills to perform risk-free recycling, hence raising health risks to individuals in associated communities and degrading the environment. Formal recycling, which embraces the best practices for effective WEEE management, is faced with several limitations, such as a lack of detailed guidelines on waste recycling, reuse, and final disposal techniques, with no opportunities for landfilling. A qualitative approach was adopted for this study. Data were gathered via questionnaires and analysed graphically. A background literature review of the assessment of informal recycling methods and associated challenges was performed. Hence, a new concept for the local management of WEEE processing was introduced. This concept limits the role of informal recyclers to WEEE collection. In this case, informal recyclers are paid for WEEE collection; they no longer engage in further WEEE processing. The results show that 48% and 40% agree to partner and collaborate with government agencies, respectively. Conversely, 52% and 40% agree and strongly agree, respectively, to limit their activities to WEEE collection only if the government is willing to pay for the services.

Heavy metals in fish nearby electronic waste may threaten consumer's health. Examples from Accra, Ghana

Electronic waste sites are rich in heavy metals contained in electronic and electric equipment waste and pose a risk of pollution if metals enter in the environment nearby. The Korle lagoon, located in the center of Accra, is receiving waste effluents from industries, households and the adjacent e-waste burning site Agbogbloshie which is the biggest in the country. Thus, the risk of heavy metal contamination of the water body and subsequent uptake in the aquatic food chain is particularly relevant. Small-scale fishing, not entering the commercial chain, occurs in the lagoon despite its consideration of biologically dead. We assessed if the exposure to heavy metals through these fish consumption is posing higher health risks than fish sold on Ghanaian markets. Using ICP-MS technology, we quantified concentrations of As, Cd, Co, Cr, Cu, Hg, Ni, Pb and Zn in fish caught from the Korle Lagoon (Trachinotus ovatus, Mugil curema and Mugil cephalus) and compared them to fish from the Tema Newtown fishing market (Scomber colias, Pseudotolithus senegallus). Cobalt and lead concentrations, typical e-waste metals, were higher in fish from the Korle lagoon, even though they were of lower trophic level. Calculated risk indices revealed risk of elevated arsenic and mercury exposure, particularly through T. ovatus from the Korle lagoon, if consumed daily as it is common in the region. This study suggests the need of monitoring programs of Ghanaian catch, with a special focus in environmental risk areas like Korle lagoon to ensure human food safety.

Waste Electrical and Electronic Fund Policy: Current Status and Evaluation of Implementation in China

With the accelerated iteration of global electronic and electrical product updates, the demand for electronic and electrical products presents a new trend in which the life cycle of electronic and electrical products is shortened. Waste electrical and electronic equipment (WEEE) products pose a great threat to the global ecological environment, and solving this problem is urgent. Therefore, governments around the world have formulated funding policies for WEEE products, which has led to continuous improvements in such policies. Along these lines, we adopt the circular economy concept, extended producer responsibility theory and life cycle assessment method to comparatively analyse and compare the different fund operation modes in China, Germany, Japan and The Netherlands. In addition, based on the data related to fund policy implementation, we point out the problems in the development of the WEEE industry in China. The analysis results show that although China is the largest WEEE market, it is still in the initial stage and lags behind Western countries in efficiency and cost management. Then, taking as an example ‘Go Green’, an O2O classified recycling platform launched in 2005, this paper performs an extended analysis of the “Internet +” recycling model, which was proposed as a WEEE fund operation solution in China. Finally, we discuss the economic impact of this study on the future implementation and valuation of WEEE fund policy.

Kidney Cadmium Concentrations in an Urban Sri Lankan Population: an Autopsy Study

Contamination and bioaccumulation of toxic heavy metals in our geo-environment is a growing public health concern. Human biomonitoring is an essential step in assessing the population risk of chronic exposure to environmental contaminants. Whole kidneys collected from a cohort of 92 deceased individuals undergoing forensic autopsies in Colombo, Sri Lanka, were analysed for cadmium (Cd) bioaccumulation using ICP-MS. Mean age of the population was 55.4 ± 15.4 years. Mean and median renal Cd concentrations of the total population were 4.38 and 2.60 μg g^-1 w/w, respectively, which were below estimated toxic ranges. Males accumulated higher levels of Cd than females (p = 0.377). Cd concentrations were higher in the < 60 age group than the > 60 age group (p = 0.92), while the highest levels were reported in 51-60 age group. However, no significant correlation was found between renal Cd concentration and age (Ʈ_b = - 0.005, p = 0.94). Individuals who smoked, chewed betel or consumed alcohol were found to have elevated renal Cd concentrations in comparison to those who did not use these substances. This is the largest autopsy study on renal Cd bioaccumulation in Sri Lanka, and the findings do not indicate a high exposure risk to environmental Cd contamination at present.

WEEE treatment and system management in Italy and Serbia: A comparison

Waste electrical and electronic equipment (WEEE) represent one of the growing waste streams in Europe, whose content of hazardous substances and valuable materials focus on how it is handled. However, there are differences between countries regarding e-waste management system in Europe. This paper analyses and presents data regarding the e-waste management system in Italy, one of the founding countries of the EU and Serbia - EU candidate country. Within this work, the following aspects were considered: legislative framework and EU directive goals in terms of e-waste, institutional setup, collection system, and existing recycling and treatment technologies. In addition, material flow analysis is used to model mass balance within WEEE treatment plants in both countries. Finally, through assessment and comparison of current systems in both countries, problems and shortages of Serbia's e-waste management system are addressed.

E-waste management and its effects on the environment and human health

Challenges in managing electronic waste (E-waste) arise from a lack of technical skills, poor infrastructure, inadequate financial support, and inactive community engagement. This study provides a systematic review of efforts to overcome these challenges in the context of inappropriate recycling protocols of E-waste and their toxic effects on human health and the environment. An inventory of end-of-life electronic products, which can be established through the creation of an environment friendly regulatory regime for recycling, is essential for the proper control of E-waste. An approach has been articulated to help implement effective management of E-waste in both developed and developing countries. Enforcement of systematic management measures for E-waste in developing countries coupled with best practices is expected to minimize adverse impacts while helping maintain a sustainable and resilient environment.

Microbial Processing of Waste Shredded PCBs for Copper Extraction Cum Separation—Comparing the Efficacy of Bacterial and Fungal Leaching Kinetics and Yields

The recycling of electronic scrap is an important subject not only from an environmental aspect but also for recovering metal resources such as copper. In this work, the microbial extraction of copper and other metals (Cu, Ni, Co, Fe and Al) present in the depopulated and shredded printed circuit board (PCB) is elaborated. Bacterial strains of A. ferrooxidans, A. thiooxidans and a fungal strain, A. niger are used for copper extraction along with other metals from shredded PCBs. An optimum metal recovery of 93% Cu was obtained at 308 K, pH 2 using 8% pulp density in 10 days by a mixed culture of A. ferrooxidans and A. thiooxidans. Whereas using A. niger, a metal recovery of 66% Cu was reported using similar experimental conditions. The results show the higher potential ability of bacteria as compared to fungus to bioleach copper. Additionally, the kinetics and mechanism of copper bioleaching from this e-waste by the chemolithotrophs and heterotrophs were evaluated. The leach liquor obtained from the optimized leaching process was subjected to separation and purification of copper as >99% pure copper sulfate using Acorga M5640 by solvent extraction.

Multi-Criteria Decision Making Approaches Applied to Waste Electrical and Electronic Equipment (WEEE): A Comprehensive Literature Review

The global demand for electrical and electronic equipment has undergone continuous growth in recent years due to the effect of industrialization and technological development. This indicates substantial quantities of e-waste that need to be managed properly to reduce their environmental impact and to avoid inappropriate forms of disposal. The purpose of this paper is to review the most popular multi-criteria decision-making approaches applied to the management of waste electrical and electronic equipment, analyzing how they are used to contribute to the improvement of management strategies along the entire supply chain. For this purpose, a methodological protocol for the collection, selection, and analysis of the scientific literature was applied, identifying 44 papers on which to conduct this study. The results showed that numerous authors have developed multi-criteria approaches, with particular attention to recycling phase. The analytic hierarchy process is the most widespread multi-criteria approach, often coupled with VIKOR, DELPHI, and TOPSIS methods. The numerous decision making criteria adopted cover different reference dimensions: environmental, economic, social, technical, and legal. Considering environmental aspects also in decision making processes means enhancing the relevance of this dimension, as well as encouraging practices that reduce the impact of toxic substances on the environment and living organisms.

A cost-benefit analysis of the downstream impacts of e-waste recycling in Pakistan

This paper presents downstream cost-benefit analysis for electronic waste (e-waste) recycling workers in Pakistan, a country that both generates large quantities of e-waste domestically and imports a significant amount from developed countries. Financial cost-benefit elements - reduction in productive capacity, lost wages, medical expenses, wages (and meals) and non-financial cost-benefit elements - opportunity cost, cost of illiteracy and value of life have been quantified. Primary data collected on site was analyzed using quantitative and qualitative methods. The estimated total net economic cost to recycling workers is between Rs.34,069 and Rs.85,478 (US$ 203-510¹) per month or an average of Rs.50,363 (US$ 300) per worker. This main finding suggests that cost exceeds by 2.6-4.7 times the estimated economic benefits derived by these workers. Related qualitative data suggests government and owners of recycling businesses are largely blind to many of the less visible costs of this industry, while recycling workers and their families appear trapped in a vicious cycle of poverty. Understanding that what can be measured can be managed and improved, a systematic assessment of informal recycling based on identified impact factors may help mitigate and ideally also motivate a shift towards formal processing that would reduce the downstream negative impacts, both visible and hidden.

Global occurrence, chemical properties, and ecological impacts of e-wastes (IUPAC Technical Report)

The waste stream of obsolete electronic equipment grows exponentially, creating a worldwide pollution and resource problem. Electrical and electronic waste (e-waste) comprises a heterogeneous mix of glass, plastics (including flame retardants and other additives), metals (including rare Earth elements), and metalloids. The e-waste issue is complex and multi-faceted. In examining the different aspects of e-waste, informal recycling in developing countries has been identified as a primary concern, due to widespread illegal shipments; weak environmental, as well as health and safety, regulations; lack of technology; and inadequate waste treatment structure. For example, Nigeria, Ghana, India, Pakistan, and China have all been identified as hotspots for the disposal of e-waste. This article presents a critical examination on the chemical nature of e-waste and the resulting environmental impacts on, for example, microbial biodiversity, flora, and fauna in e-waste recycling sites around the world. It highlights the different types of risk assessment approaches required when evaluating the ecological impact of e-waste. Additionally, it presents examples of chemistry playing a role in potential solutions. The information presented here will be informative to relevant stakeholders seeking to devise integrated management strategies to tackle this global environmental concern.

Utilizing an integrated assessment scheme for sustainable waste management in low and middle-income countries: Case studies from Bosnia-Herzegovina and Mozambique

Solid waste management assessment methods that simultaneously analyze the economic, social and environmental dimensions are limited. Tools are rarely applied in developing countries because of several constraints encountered during their implementation (e.g. lack of data availability and difficulties concerning data interpretation), consequently hampering the development of sustainable solid waste management practices. In addition, the incorporation of stakeholders in most decision-making tools and processes, as well as the availability of credible data in developing countries is often limited. To address these issues, this paper presents one of the first large scale studies, utilizing a tool, named Integrated Assessment Scheme (IAS). Use of IAS provides a holistic, integrated approach evaluating the economic, environmental and social dimensions in order to support the decision making process and to facilitate more sustainable waste management in low and middle-income countries. The use of IAS in the two case studies from Bosnia-Herzegovina and Mozambique suggests its suitability to communities in similar contexts. However, its limitations are also discussed.

Severe dioxin-like compound (DLC) contamination in e-waste recycling areas: An under-recognized threat to local health

Electrical and electronic waste (e-waste) burning and recycling activities have become one of the main emission sources of dioxin-like compounds (DLCs). Workers involved in e-waste recycling operations and residents living near e-waste recycling sites (EWRS) are exposed to high levels of DLCs. Epidemiological and experimental in vivo studies have reported a range of interconnected responses in multiple systems with DLC exposure. However, due to the compositional complexity of DLCs and difficulties in assessing mixture effects of the complex mixture of e-waste-related contaminants, there are few studies concerning human health outcomes related to DLC exposure at informal EWRS. In this paper, we have reviewed the environmental levels and body burdens of DLCs at EWRS and compared them with the levels reported to be associated with observable adverse effects to assess the health risks of DLC exposure at EWRS. In general, DLC concentrations at EWRS of many countries have been decreasing in recent years due to stricter regulations on e-waste recycling activities, but the contamination status is still severe. Comparison with available data from industrial sites and well-known highly DLC contaminated areas shows that high levels of DLCs derived from crude e-waste recycling processes lead to elevated body burdens. The DLC levels in human blood and breast milk at EWRS are higher than those reported in some epidemiological studies that are related to various health impacts. The estimated total daily intakes of DLCs for people in EWRS far exceed the WHO recommended total daily intake limit. It can be inferred that people living in EWRS with high DLC contamination have higher health risks. Therefore, more well-designed epidemiological studies are urgently needed to focus on the health effects of DLC pollution in EWRS. Continuous monitoring of the temporal trends of DLC levels in EWRS after actions is of highest importance.

Understanding Environmental Pollutions of Informal E-Waste Clustering in Global South via Multi-Scalar Regulatory Frameworks: A Case Study of Guiyu Town, China

The recycling of e-waste by the informal sector has brought countries in the Global South raw materials (e.g. metals and plastics), second-hand electronic equipment and components, and economic opportunities in conjunction with appalling environmental pollutions and health problems. Despite the longstanding international and national legislation regulating transnational trade and domestic recycling, informal e-waste economies are still clustering in many Global South countries. This study offers historically and geographically specific explanations of this conundrum, by interrogating the multi-scalar regulatory frameworks in which the informal e-waste economies and their pollutions are embedded, by drawing on China, particularly the former global e-waste hub-Guiyu town, as the case study. We argue that the contested and problematic application of current international and national legislation in regulating e-waste is in part pertaining to the slippery definition of what counts as “e-waste” and its paradoxical nature as both resources and pollutants. At the global scale, trajectories of global e-waste flows are shaped by the multitude of loopholes, contradictions and ambiguous articles left by the Basel Convention and by different countries’ disparate attitudes towards the e-waste trade. At the national scale, the ambiguities and contradictions in the Basel Convention have been passed on to and shaped China’s national e-waste regulatory frameworks. China’s equivocal legislation, paradoxical attitude, and formal enterprises’ weak competence contribute to the rise of informal e-waste recycling in Guiyu. Yet, China’s e-waste regime has been greatly restructured within the past decade, with formal recycling enterprises playing an increasingly significant role.

Application of an Integrated Assessment Scheme for Sustainable Waste Management of Electrical and Electronic Equipment: The Case of Ghana

The effective management of solid waste, including waste electrical and electronic equipment (WEEE) in developing countries poses significant challenges. This paper reports on the development and utilization of a multi-criteria tool to improve the management of WEEE in Agbogbloshie, in Ghana. The tool was able to successfully evaluate key economic, social and environmental factors faced by workers and to suggest areas for improvement. In particular, the evaluation and comparison of different scenarios suggested that the best solution is the evolution from informal to formal management of WEEE, with workers provided with personal protective equipment, and the introduction of refurbishment activities, with the sale of components in the second-hand market. While it would require further use in other contexts, the tool could be adapted and employed for a range of other waste streams and in other developing countries.

Determinants of Individuals’ E-Waste Recycling Decision: A Case Study from Romania

Due to the increase of the amount of electrical and electronical equipment waste (e-waste), the understanding of individual consumers’ main decision triggers represents a key point in increasing the quantity of recycled e-waste. A series of studies from the literature have shown a positive relationship between the consumers’ attitude, awareness, self-efficacy, social norms, and their e-waste recycling intention, as well as the positive influence between the intention and the manifested behavior. Additional to these determinants, in the present study, the influence of social media was analyzed along with the actions taken by the government and nongovernmental organizations, with the purpose to include and to capture, as much as possible, a high amount of determinants in the e-waste recycling process. Nevertheless, the demographic or socio-economic variables, such as age, gender, income, education, number of family members, etc., have shown over time to have a contribution to predicting the consumers’ pro-recycling behavior. As on one side, in the research literature, the opinions related to which of the demographic or socio-economic factors can have an impact on the recycling behavior have been divided and, on another side, a series of researchers believe that the discrepancies in the findings of different studies can be due to culture in various countries, in this paper we conducted such an analysis with reference to the Romania’s case. The results have shown that the demographic variables, such as age and gender, can have a contribution to predicting residents’ pro-e-waste recycling behavior. Based on these findings, the policymakers can gain a better understanding of the e-waste recycling phenomenon and on its main triggers, with results in creating better policies for sustaining a proper e-waste managing system.

Long-term effect of E-waste dismantling activities on the heavy metals pollution in paddy soils of southeastern China

The heavy metal pollution in soils has attracted a growing concern from environmental researchers worldwide. Heavy metals derived from E-waste dismantling process now is one of the main pollution sources. Wenling city is one of the large E-waste dismantling sites as well as a commercial grain production area in China. In this study, the Cd, Cu, Ni, Pb and Zn concentrations of paddy soils were determined to reveal the temporal trends over the past decade based on the samples collected from 2006 a (96) and 2016 a (167), respectively. From 2006 a to 2016 a, the averages values of Cd, Cu, Ni and Zn concentrations in soils increased by 0.11, 11.81, 1.01 and 6.82 mg kg^-1, respectively. The average concentration of Pb in soils decreased by 14.06 mg kg^-1. All of the five heavy metals shared the similar spatial distribution patterns with high-concentration values located in northwestern part of the study area. The results of principal component analysis (PCA) revealed that the E-waste was the main source of pollution for Cd, Cu, Pb and Zn in soils. The spatial patterns revealed by local Moran' I indicated that the northwestern part were identified as priority areas for soil heavy metal remediation. During the last decade, a continuing increase trend of the concentrations of heavy metals in soils was found, however, the other parts of the study area had an obvious decrease trend of heavy metals in soils under the implementation of environmental protection policies. Therefore, sustainable remediation measures and E-waste dismantling management are necessary to reduce heavy metal concentrations in specific areas of Wenling.

Impact of Economic Growth, Environmental Pollution, and Energy Consumption on Health Expenditure and R&D Expenditure of ASEAN Countries

The purpose of the current study was to examine the determinants of R&D expenditure and health expenditure of ASEAN countries. The research objectives were developed to analyze the short-term as well as the long-term impact of economic growth, environmental pollution, and energy consumption on health and R&D expenditures. The data was collected for ten years for ASEAN countries using the Auto-Regressive Distributed Lag (ARDL) approach, which helped the researcher to assess long-run as well as the short-run association of these variables. The findings revealed that environmental pollution, energy consumption, and economic growth had a significant positive impact on health expenditure as well as on R&D expenditure of ASEAN countries in long-run. The findings further revealed that environmental pollution and economic growth had a significant impact on R&D expenditure in short-run; however, there was no significant impact of energy consumption on R&D expenditure in short-run. It was also found that there was no significant impact of any of the independent variables, i.e., energy consumption, economic growth, and environmental pollution, on health expenditure in short-run. The current study and findings have significant implications in theory and practice.