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The decade-long effort to control e-waste in China has made significant progress from haphazard disposal to organized recycling, but environmental research suggests that exposure to volatile organic compounds (VOCs) and metals/metalloids (MeTs) still poses plausible health risks. To investigate the exposure risk faced by children and identify corresponding priority control chemicals, we evaluated the carcinogenic risk (CR), non-CR, and oxidative DNA damage risks of VOCs and MeTs exposure in 673 children from an e-waste recycling area (ER) by measuring urinary exposure biomarker levels. The ER children were generally exposed to high levels of VOCs and MeTs. We observed distinctive VOCs exposure profiles in ER children. In particular, the 1,2-dichloroethane/ethylbenzene ratio and 1,2-dichloroethane were promising diagnostic indexes for identifying e-waste pollution due to their high accuracy (91.4%) in predicting e-waste exposure. Exposure to acrolein, benzene, 1,3-butadiene, 1,2-dichloroethane, acrylamide, acrylonitrile, arsenic, vanadium, copper, and lead posed considerable CR or/and non-CR and oxidative DNA damage risks to children, while changing personal lifestyles, especially enhancing daily physical exercise, may facilitate mitigating these chemical exposure risks. These findings highlight that the exposure risk of some VOCs and MeTs is still non-negligible in regulated ER, and these hazardous chemicals should be controlled as priorities. [Display omitted] • We profile the exposure risk of VOCs and MeTs in children from a regulated ER. • Exposure to VOCs and MeTs is significantly associated with oxidative DNA damage. • Exposure to six VOCs and four MeTs poses considerable health risks to ER children. • Enhancing physical exercise facilitates mitigating pollutant exposure risks. • TGA/PGA ratio and TGA may be used as diagnostic indexes to identify e-waste pollution. [ABSTRACT FROM AUTHOR]

Benzene, toluene, ethylbenzene, and xylene (BTEX) can be released during extensive activities associated with the disposal of electronic waste (e-waste), which might pose deleterious health effects on workers. In this study, pollution profiles of BTEX in air and their urinary excretive profiles in occupational workers were investigated in a typical e-waste recycling industrial park. The results showed that the workers in the park were generally exposed to high levels of BTEX. The median levels of urinary metabolites were approximately 6-orders of magnitude higher than those of unmetabolized BTEX, indicating that pollutants efficiently metabolize at those occupational levels. The analytes presented differential profiles in external and internal exposure. Among the metabolites, significant correlation (p < 0.05) was observed between N-acetyl-S-benzyl- L -cysteine (S-BMA) concentration and atmospheric individual BTEX derived from the e-waste recycling area, suggesting that S-BMA is a potential marker for BTEX exposure to e-waste occupational workers. Notably, 95.2 % of all the workers showed a cumulative carcinogenic risk induced by BTEX exposure via inhalation, with 99.9 % of the carcinogenic risk distribution based on concentration of benzene metabolite (N-acetyl-S-(phenyl)- L -cysteine) exceeding 1.0E-6. This study holds potential in providing valuable inferences for the development of remediation strategies focusing on BTEX exposure reduction to protect workers' health at e-waste recycling industries. [Display omitted] • Ambient and biomonitorial of BTEX were studied in a typical e-waste recycling park. • Urinary metabolites levels were much higher than unmetabolized BTEX in workers. • HA was found to be the absolute major component in urinary samples. • Urinary S-BMA might act as a tracer for BETX derived from e-waste disposal. • Biomonitoring exposure to benzene showed 99.9 % cumulative carcinogenic risk. [ABSTRACT FROM AUTHOR]

Melamine and its derivatives are used as additives in flame retardants. Moreover, melamine-containing consumables such as laminates, adhesives, glues, and plastics are extensively used in electronic products. Nevertheless, there is no information concerning the identification of melamine and its derivatives during e-waste recycling. In the present study, the occurrence of melamine and three of its derivatives (cyanuric acid, ammelide, and ammeline) was identified for the first time in indoor dust from typical e-waste recycling areas and adjacent rural communities. Urban communities situated about 80 kilometers away were used as a control. The target analytes were detected in almost all the dust samples, which were dominated by melamine and cyanuric acid. The total concentrations of melamine and its derivatives varied among sampling locations in the following order: e-waste workshops (geometric mean: 15,018 ng/g) > urban houses (9060 ng/g) > local rural houses (6204 ng/g) > local streets (201 ng/g). This suggested that e-waste dismantling/recycling activities mainly contributed to the abundant emission of melamine and its derivatives in e-waste dust. Correlation analysis indicated that melamine and its derivatives were similarly applied in electronic products and e-waste recycling resulted in common emissions. The combined toxicity of melamine and its derivatives on human bladder cancer cells was observed. Importantly, Monte Carlo analysis was used to determine that the estimated daily intakes of these chemicals via dust ingestion for occupational e-waste recycling workers were 2.5–9 times higher than the estimated daily intakes for adult residents in both adjacent local communities and urban areas. These results are the first to demonstrate that e-waste dismantling workers are more vulnerable to the exposure risk posed by the presence of melamine and its derivatives in e-waste dust, which deserves more research attention. [Display omitted] • Elevated emissions of melamine in e-waste dust. • Melamine and cyanuric acid were the dominated analytes in all the dust samples. • E-waste dismantling activities mainly contributed to massive emissions of ∑Melamines in e-waste dust. • Enhanced cell toxicity was observed in T24 cells under co-exposure condition. • E-waste workers are more vulnerable for exposure risk posed by ∑Melamines. [ABSTRACT FROM AUTHOR]

High Br-containing polystyrene (PS) plastics are generated in large quantities during the dismantling of waste CRT TVs. Debromination and reuse of Br-containing PS plastics is a critical technical challenge. Here, we demonstrate a method for combining alkaline hydrothermal debromination and co-blending granulation to achieve the regeneration of high Br-containing PS plastics. The results show the bromine concentration in PS was reduced from 49,300 mg/kg to 7420 mg/kg and from 169,000 mg/kg to 9340 mg/kg, with a removal efficiency of 84.95% at least. Then, we co-blended the debromination PS products (1 part) with qualified normal PS plastics (9 parts) for granulation. Compared to the qualified normal PS, the physical properties of the co-blended plastics remained stable in terms of the melt index, tensile strength, flexural strength andflexural modulus, which made it have good application prospects. Meanwhile, the Br concentration of co-blended PS plastics were further reduced to less than 1000 mg/kg. In summary, we provide a promising outlook of alkaline hydrothermal and co-blending (1 +9) granulation as an efficient approach for Br-containing PS plastics upgrading recycling. This study provides a novel method for combining alkaline hydrothermal treatment and co-blending modification granulation process to achieve the upgrading recycling of Br-containing waste plastics. The results show the Br concentration in PS was reduced from 169,013 ppm to 9344 ppm, with a removal efficiency of 94.47%. The debromination PS products (1 part) were blended with qualified normal PS plastics (9 parts) for granulation. Compared to the qualified normal PS, the physical properties of the co-blended plastics remained basically stable, which made it have good application prospects. Also, the reuse of waste plastic can make contribution for the carbon reduction. [Display omitted] • Waste Br-containing plastics can be debrominated by alkaline hythothermal method. • The physical properties of the co-blended plastics (1/10 part) remained stable. • The profit for processing each tonne of high Br-containing PS plastic is $42.59/t. • Up-cycling of waste Br-containing PS plastics can be attained. [ABSTRACT FROM AUTHOR]

Abstract: A novel recycling route using acid leaching, reduction and gelatin method was applied to recycle spent Zn–C batteries into more valuable magnetic nano-crystalline ferrites; Mn1−x Zn x Fe2O4 (with x =0.2–0.8). The cost of this recycling technology has economical advantages, which holds promising industrial application products. Dried gel thermal decomposition process was monitored by simultaneous differential thermal analysis–thermogravimetry–differential scanning calorimetry. Phase composition, morphological and magnetic properties of the as-prepared precursors were characterized using X-ray powder diffraction, transmission electron microscopy, Fourier transform infrared and vibrating sample magnetometer. Single-phase agglomerated cubic ferrites with crystal sizes in the range 21–41nm were detected. The obtained magnetization values are significantly lower than that of the bulk ferrite and showed a gradual increase with increasing Zn-substitution with an obvious decrease at x =0.6. On the other hand, a reverse trend was exhibited by coercivity. The effect of Zn-substitution on both structural and magnetic properties, paved the way to suggest proper cation distributions for the investigated system. [Copyright &y& Elsevier]

Abstract: To reduce cost and secondary pollution of spent lithium ion battery (LIB) recycling caused by complicated separation and purification, a novel simplified recycling process is investigated in this paper. Removal of magnesium is a common issue in hydrometallurgy process. Considering magnesium as an important additive in LIB modification, tolerant level of magnesium in leachate is explored as well. Based on the novel recycling technology, Li[(Ni1/3Co1/3Mn1/3)1−x Mg x ]O2 (0≤ x ≤0.05) cathode materials are achieved from spent LIB. Tests of XRD, SEM, TG-DTA and so on are carried out to evaluate material properties. Electrochemical test shows an initial charge and discharge capacity of the regenerated LiNi1/3Co1/3Mn1/3O2 to be 175.4mAhg−1 and 152.7mAhg−1 (2.7–4.3V, 0.2C), respectively. The capacity remains 94% of the original value after 50 cycles (2.7–4.3V, 1C). Results indicate that presence of magnesium up to x =0.01 has no significant impact on overall performance of Li[(Ni1/3Co1/3Mn1/3)1−x Mg x ]O2. As a result, magnesium level as high as 360mgL−1 in leachate remains tolerable. Compared with conventional limitation of magnesium content, the elimination level of magnesium exceeded general impurity-removal requirement. [Copyright &y& Elsevier]

Bisphenols and benzophenone UV-filters are hazardous, high production volume chemicals. There is concern that these contaminants could leach into the environment or be recycled into new products during waste management. To investigate this, nine bisphenols and five benzophenones were quantified in Norwegian e-waste and car fluff. To understand their leachability, equilibrium passive sampling methodology, using polyoxymethylene (POM), was calibrated for these substances, many of which for the first time. This method can differentiate freely dissolved substances in the aqueous phase from those sorbed to suspended colloids and microplastics in the leachate water. Equilibrium POM partitioning was reached within 14 days of shaking; all bisphenols and benzophenone UV-filters exhibited linear isotherms (R2 ranged from 0.83 to 1.0), when deriving POM-water partition coefficients (K POM). Bisphenol A and bisphenol F displayed the highest concentrations, with maximum levels of 246,000 and 42,400 ng g−1, respectively. Logarithms of waste-water partition coefficients (log K waste) ranged from 1.7 (benzophenone 2) to 4.5 (bisphenol P). The established K POM values agreed with measured K waste values (within a factor of ~3), unlike octanol-water partition coefficients. This indicated that POM is a better surrogate for waste plastic partitioning than octanol. Results are discussed in the context of assessing risks from waste management in a circular economy. [Display omitted] • First e-waste & vehicle fluff analysis of many bisphenol analogues. • First e-waste & vehicle fluff analysis of many benzophenone UV-filters. • POM calibrated as a passive sampler for bisphenols and benzophenone UV-filters. • POM used to measure leachability and sorption behaviour in e-waste & vehicle fluff. • Relevance for managing bisphenols and benzophenones in a circular economy. [ABSTRACT FROM AUTHOR]

Uncontrolled electronic-waste (e-waste) recycling processes have induced serious environmental pollution and human health impacts. This paper reviewed studies on the wide range of toxic chemicals through the use of primitive recycling techniques, their transfer to various ecological compartments, and subsequent health impacts. Results indicated that local food items were heavily polluted by the pollutants emitted, notably heavy metals in vegetables, rice, fish and seafood, and persistent organic pollutants (POPs) in livestock. Dietary exposure is the most important exposure pathway. The associations between exposure to e-waste and high body burdens of these pollutants were evident. It seems apparent that toxic chemicals emitted from e-waste activities are causing a number of major illnesses related to cardiovascular, digestive and respiratory systems, according to the information provided by a local hospital (Taizhou, an e-waste recycling hot spot in China). More epidemiological data should be made available to the general public. It is envisaged that there are potential dangers of toxic chemicals passing on to the next generation via placental transfer and lactation. There is a need to monitor the development and health impacts of infants and children, born and brought up in the e-waste sites. [Display omitted] • Local food in e-waste sites is heavily polluted, notably Cd, Pb, PBDEs and PCBs. • Dietary exposure is more related to the body burdens of toxic chemicals. • Toxicants from e-waste sites cause cardiovascular, digestive and respiratory related illnesses. • Epidemiological data in e-waste recycling sites should be made available to the general public. • Understanding of adverse health impacts of toxicants on younger generation should be investigated. [ABSTRACT FROM AUTHOR]

Electronic waste (e-waste) is one of the fastest-growing solid wastes and has become an urgent issue due to the potential adverse consequences of exposure to emitted toxic pollutants, especially for these occupational exposed workers and local residents. In this review, the environmental occurrences, emission characteristics, sources, and possible adverse effects of polycyclic aromatic hydrocarbons (PAHs) emitted from primitive e-waste dismantling activities are summarized. In general, the atmospheric levels of PAHs at typical e-waste sites, e.g., in Guiyu, China, have substantially decreased by more than an order of magnitude compared with levels a decade ago. The PAH concentrations in soil from old e-waste sites in China are also generally lower than those at newly emerged e-waste sites in India, Pakistan and Ghana. However, elevated concentrations of PAHs have been reported in human milk, hair and urine from the populations near these e-waste sites. Source apportionment both from bench-scale studies to field observations has demonstrated that the pyrolysis and combustion processing of electronic circuit board are mainly responsible for the emissions of various PAHs. In addition, some specific PAHs and their derivatives, such as triphenylbenzene, halogenated and oxygenated PAHs, have frequently been identified and could be considered as indicators in routine analysis in addition to the 16 U.S. EPA priority PAHs currently used. [Display omitted] • Primitive e-waste dismantling activities have caused widespread PAH contamination. • Emissions, exposure and potential health effects of PAHs are reviewed. • Environmental occurrences of PAHs have decreased at old e-waste sites in China. • New tracers and PAH derivatives specific to e-waste activities are discussed. • Future research directions should include novel tracers and PAH derivatives. [ABSTRACT FROM AUTHOR]

Since Stockholm Convention listed polybrominated diphenyl ethers (PBDEs) as persistent organic pollutants and banned their addition, alternative halogen flame retardants (AHFRs) have been substituted for PBDEs. This study systematically investigates the change trends of PBDEs and AHFRs from typical e-waste plastics and dust, as well as clarifying human exposure risks of PBDEs in formal and informal e-waste recycling enterprises, repair store and residential building. The results show that the PBDEs levels in five typical types of e-waste vary in the range of 1.08 × 10−3-30.8 μg/g, meeting the requirements of RoHS regulation. Compared with the residential buildings (1.49–1.68 μg/g), PBDEs in the dust from the formal and informal e-waste recycling enterprises are much higher, ranging from 4.70 to 536 μg/g. BDE-209 is the main congener in most e-waste plastic and dust samples. Meanwhile, AHFRs have become the important composition (3.5–61.5%) in e-waste plastics, while its contribution is lower in dust, implying the higher enrichment efficiency of PBDEs. For PBDEs exposure, the dust intake risk of PBDEs is much higher than skin contact for the workers, and the highest hazard quotient (HQ) value (1.40 × 10−1) and cancer risk (CR) value (1.21 × 10−7) both imply safe exposure levels. [Display omitted] • It firstly systemically explores the change trends and health risks of PBDEs. • PBDEs show a decreasing trend and have been gradually substituted for AHFRs. • The enrichment efficiency of PBDEs is higher than AHFRs in dust. • PBDEs exposure in Macau are much higher than that in Foshan. • Hazard quotient and cancer risk both imply safe exposure levels. [ABSTRACT FROM AUTHOR]

Since Stockholm Convention listed polybrominated diphenyl ethers (PBDEs) as persistent organic pollutants and banned their addition, alternative halogen flame retardants (AHFRs) have been substituted for PBDEs. This study systematically investigates the change trends of PBDEs and AHFRs from typical e-waste plastics and dust, as well as clarifying human exposure risks of PBDEs in formal and informal e-waste recycling enterprises, repair store and residential building. The results show that the PBDEs levels in five typical types of e-waste vary in the range of 1.08 × 10−3-30.8 μg/g, meeting the requirements of RoHS regulation. Compared with the residential buildings (1.49–1.68 μg/g), PBDEs in the dust from the formal and informal e-waste recycling enterprises are much higher, ranging from 4.70 to 536 μg/g. BDE-209 is the main congener in most e-waste plastic and dust samples. Meanwhile, AHFRs have become the important composition (3.5–61.5%) in e-waste plastics, while its contribution is lower in dust, implying the higher enrichment efficiency of PBDEs. For PBDEs exposure, the dust intake risk of PBDEs is much higher than skin contact for the workers, and the highest hazard quotient (HQ) value (1.40 × 10−1) and cancer risk (CR) value (1.21 × 10−7) both imply safe exposure levels. [Display omitted] • It firstly systemically explores the change trends and health risks of PBDEs. • PBDEs show a decreasing trend and have been gradually substituted for AHFRs. • The enrichment efficiency of PBDEs is higher than AHFRs in dust. • PBDEs exposure in Macau are much higher than that in Foshan. • Hazard quotient and cancer risk both imply safe exposure levels. [ABSTRACT FROM AUTHOR]

This work examines two recycling processes for spent Li/MnO2 and Li-ion batteries. The anode, cathode and electrolyte (LiPF6) were submitted to one of the following procedures: (a) calcination at 500°C (5h) followed by solvent extraction to recover lithium salts (fluoride, phosphate) in good yield (90wt%). The residual solid was treated with H2SO4 containing H2O2 and on evaporation gave high purity grade cobalt or manganese sulfate; (b) fusion with KHSO4 (500°C, 5h). The resulting aqueous solution was added dropwise to a solution of NaOH, giving cobalt or manganese as impure precipitate. Addition of KF precipitated high purity grade LiF in moderate yield (50wt%). The final aqueous solution on treatment with calcium sulfate precipitated the corresponding phosphate and fluoride salts. [Copyright &y& Elsevier]

E-wastes comprise complex combinations of potentially toxic elements that cause detrimental effects of the environmental contamination; besides their posing threat, most of the products also contain valuable and recoverable materials (Li, Au, Ag, W, Se, Te, etc.), which make them distinct from other forms of industrial wastes. Most of these value-added elements which are primarily employed in electronic goods are disposed of by incineration and land-filling. This is a serious issue besides just environmental pollution, as IUPAC recognized that such ignorance of or poor attention to e-waste recycling has put several elements in the periodic table to the list of endangered elements. Recycling these wastes utilized for electrocatalytic water splitting to produce H 2. These recovered e-wastes materials are used as electrocatalysts for the water-splitting, additives to enhance reaction kinetics, and substrate electrodes as well. Recycling and recovery of value-added materials in the view of applying them to electrocatalytic water splitting with endangered elements' perspective have not been covered by any recent review so far. Hence, this review is dedicated to discussing the opportunities available with recycling e-wastes, types of value-added materials that can be recovered for water splitting, strategies exploited, and prospects are discussed in details. [Display omitted] • The significance of the electrocatalytic activity of endangered elements. • Nexus between electronic waste and elemental scarcity is analyzed. • A road map of e-waste utilization in the electrocatalysis is attempted. • Relationship between the e-waste elements and energy conversion catalyst. [ABSTRACT FROM AUTHOR]

Informal e-waste recycling processes emit various air pollutants. While there are a number of pollutants of concern, little information exists on volatile organic compounds (VOCs) releases at e-waste sites. To assess occupational exposures and estimate health risks, we measured VOC levels at the Agbogbloshie e-waste site in Ghana, the largest e-waste site in Africa, by collecting both fixed-site and personal samples for analyzing a wide range of VOCs. A total of 54 VOCs were detected, dominated by aliphatic and aromatic compounds. Mean and median concentrations of the total target VOCs were 46 and 37 μg/m3 at the fixed sites, and 485 and 162 μg/m3 for the personal samples. Mean and median hazard ratios were 2.1 and 1.4, respectively, and cancer risks were 4.6 × 10-4 and 1.5 × 10-4. These risks were predominantly driven by naphthalene and benzene; chloroform and formaldehyde were also high in some samples. Based on the VOC composition, the major sources were industry, fuel evaporation and combustion. The concentration gradient across sites and the similarity of VOC profiles indicated that the e-waste site emissions reached neighboring communities. Our results suggest the need to protect e-waste workers from VOC exposure, and to limit emissions that can expose nearby populations. [Display omitted] • This is the first study to assess both personal and ambient VOCs in e-waste site. • VOC levels in personal samples were much higher than that in fixed-site samples. • Local industrial use, fuel evaporation and combustion were the main sources. • VOC emissions from the e-waste site polluted the neighboring environment. • Health risks exceeded guideline levels and were mainly due to naphthalene and benzene. [ABSTRACT FROM AUTHOR]

• Primitive e-waste dismantling led to the highest OPE levels in the atmosphere. • OPEs in the urban region were largely derived from industrial emissions. • Surface evaporation and air advection also contributed OPEs in the urban air. • The compositions at the background site suggest atmospheric reaction loss of OPEs. • Emission sources of TEP and TDCIPP nearby the background site were observed. Organophosphate esters (OPEs) are a focus of research because they are ubiquitous in the environment; however, there is still a limited understanding of the behaviors and fate of OPEs in the environment. In this study, we measured OPEs in fine particulate matter (PM 2.5) collected from three regions in South China that have potentially different sources. The concentrations of ∑OPEs in the rural electronic waste (e-waste) recycling area (3852–57,695 pg/m3 with a median of 10,955 pg/m3) were significantly higher than those in the urban and background areas with concentrations of 314–9721 pg/m3 (median = 2346 pg/m3) and 667 and 109,599 pg/m3 (median = 2170 pg/m3), respectively. The OPE compositions in the urban and e-waste areas were generally similar. Correlations analysis with other components of PM 2.5 (organic carbon, elemental carbon, and water soluble ions) indicated primary industrial and e-waste sources of OPEs in the urban and e-waste regions, respectively. Correlation analysis also revealed that relative humility played an important role in their air concentrations in the urban and background regions. The air-parcel backward trajectories of the background site demonstrated regional atmospheric transport of OPEs to this region from both the eastern industrial cities and the northern e-waste recycling region. [ABSTRACT FROM AUTHOR]