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Due to the far distance impact on resident, aquatic and soil ecosystem health, food waste disposal becomes the focus of municipal waste strategy in developing countries. Shanghai is a leading city in China, its evolution of food waste management can indicate the coming future of the nation. In this city, from 1986 to 2020, the open dumping, landfill and incineration of food waste had been gradually banned, replaced by centralized compost and anaerobic digestion and other recovery ways. This study selected ten scenarios, ever used for food/mixed waste disposal in Shanghai, and analyzed the environmental impact change during the period 1986-2020. Life cycle assessment showed that although the generation of food waste raised rapidly, the total environmental impact, which was dominated by Freshwater Aquatic Ecotoxicity Potential, displayed a sharp decrease as 96.09 %, and Global Warming Potential decreased by 28.14 %. Substantial efforts should be made to improve the collection rate of biogas and landfill gas to reduce environmental impact, and quality of residues from anaerobic digestion and compost plants should be improved and utilized in its legal ways. Driving forces for the goal of sustainable food waste management in Shanghai involved economic development, environmental regulations and the supporting national/local standards., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Spent lithium-ion batteries (LIBs) have been one of the fast-growing and largest quantities of solid waste in the world. Spent graphite anode, accounting for 12-21 wt% of batteries, contains metals, binders, toxic, and flammable electrolytes. The efficient recovery of spent graphite is urgently needed for environmental protection and resource sustainability. Recently, more and more studies have been focused on spent graphite recycling, while the advance and challenges are rarely summarized. Hence, this study made a comprehensive review of graphite recycling including separation, regeneration, and synthesis of functional materials. Firstly, the pretreatment of graphite separation was overviewed. Then, the spent graphite regeneration methods such as leaching, pyrometallurgy, their integration processes, etc. were systematically introduced. Furthermore, the modification strategies to enhance the electrochemical performance were discussed. Subsequently, we reviewed in detail the synthesis of functional materials using spent graphite for energy and environmental applications including graphene, adsorbents, catalysts, capacitors, and graphite/polymer composites. Meanwhile, we briefly compared the economic and environmental benefits of graphite regeneration and other functional materials production. Finally, the technical bottlenecks and challenges for spent graphite recycling were summarized and some future research directions were proposed. This review contributes to spent LIBs recycling more efficiently and profitably in the future., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The rapid development of new energy technology leads to explosive growth of lithium-ion batteries (LIBs) industry which greatly alleviates the problems of environmental pollution and energy shortage. However, how to realize resource circulation of critical metals including lithium (Li) and cobalt (Co) becomes the new problem of LIBs industry. This paper proposes an improved thermal reduction technology to efficiently recycle Li and Co from spent LIBs, where cheap urea is applied as the only additive to provide ammonia (NH 3 ). By thermal reduction, LiCoO 2 was thermally reduced into water-soluble lithium carbonate and water-insoluble cobalt metal Under the optimal conditions, 99.96% Li with nearly 100% selectivity was obtained by water leaching. More importantly, the concept of "oxygen elements removal (OER)" was proposed to explain the metal extraction from spent LIBs, which could help to describe the reaction mechanism as O-cage digestion mechanism. Furthermore, metal extraction from spent LIBs was re-understood as "seeking an applicable reductant", which provided a fresh perspective for understanding Li selective recovery. These concepts and findings can provide some inspiration for metal recovery from spent LIBs., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Spent lithium-ion batteries (LIBs) recycling has attracted much attention because it is highly favorable to environment protection and sustainable development. Developing a cleaner method for metals extraction can greatly reduce risk of secondary pollution. Chlorinating technology has been proved as an efficient method for metals extraction instead of traditional hydrometallurgy. In this paper, cathode materials from spent LIBs could be rapidly converted into metal chlorides by NH 4 Cl roasting at 623 K for 20 min. The results indicated nearly 100% metal leaching rates were achieved. Further, in-depth study is performed to obtain the mechanism function of chlorinating conversion based on roasting and TGA experiments. The apparent activation energy as 73.40 kJ/mol was firstly obtained, and then the reaction model of chlorination reaction was determined by model fitting and verifying. Herein, sub-reactions of chlorination reaction were figured out and their contributions were used to determinate reaction controlling mechanisms of chlorination reaction. The results indicated that nucleation reaction played a leading role in the initial stage (0.05 <α < 0.43) while phase boundary reaction took the control in next stage (0.43 <α < 0.95), which gave a good explanation to activation energy change. Finally, our findings provided inspirations for studying the controlling mechanism of gas-solid reaction., (Copyright © 2020 Elsevier B.V. All rights reserved.)

A targeted extraction technology for recycling lithium from spent lithium transition metal oxides (LTMO) type batteries is developed in this paper. The chlorinating technology with ammonium chloride as the only additive is employed and controlled to selectively extract lithium. High lithium extraction rate with a low selectivity was first obtained at non-controlled chlorinating conditions. During this process, it was found that the reducing driving force (RDF) played a vital role in metals extraction. Once RDF was controlled at a low level, lithium elements could be targetedly extracted out while other metal elements still remained in the residues. The results showed that 91.73% lithium elements were leached out with a selectivity of 90.04% at the optimal conditions. Further, the mechanism was proposed to explain the release behavior of metals from cathode materials from the perspective of extracting driving force. These principles also offer inspiration for metal selective extraction fields such as metallurgy and recovery of complex systems including multiple metals., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Polybrominated diphenyl ethers (PBDEs) are a class of widely used flame retardants, and their residue in the environment may threaten the ecosystem and human health. The neurodevelopmental toxic effects of PBDEs have been verified in previous studies, but the mechanisms are still unclear. Behavioral analysis and transcriptomics were performed in this study to assess the neurodevelopmental toxic effects of PBDEs on zebrafish embryos and larvae, and the potential mechanisms. The embryos were collected after fertilization and exposed to control (0.05% DMSO), 10, 50, 100 (ug/L) 2, 2', 4, 4'-tetrabromodiphenyl ether (BDE-47) for 7 days. The locomotion parameters of larvae were recorded and analyzed by a behavioral analysis system (EthoVision XT, Noldus). Enrichment of functions and signaling pathways of differentially expressed genes (DEGs) were analyzed by GO and DAVID database. The comparison with the control group showed adverse developments such as low hatching rate, high mortality rate, alterative heart rate, and abnormal spontaneous tail coiling frequency of embryos (24hpf). For the zebrafish larvae, behavioral analyses results suggested decreased activities and movements of the treatment in the light-dark period at 120, 144 and 168hpf, especially the 50 and 100μg/L groups. The affected functions included steroid hormone regulation, neuro regulation, circadian regulation, cardioblast differentiation, immune-related regulation. The enrichment of KEGG pathways were Hedgehog signaling (Shh), Toll-like receptor signaling, FoxO signaling, and Steroid biosynthesis pathway. Hedgehog signaling pathway was further verified via RT-qPCR for its major role in the development of neurogenesis. The mRNA levels of Shh pathway indicated the inhibition of Shh signal in our study since shha, patched1, gli1 and gli2 genes were significantly down-regulated. In summary, PBDEs might influence the neurodevelopment of zebrafish in the early life stage by multiple toxic signaling pathways alteration., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Bisphenol A (BPA) is a well-known xenobiotic endocrine disrupting chemical, with estrogenic activity and many other potential biological effects. Although multiple toxicities have been reported for BPA, molecular mechanisms underlying the transgenerational toxic effects of BPA are still underestimated., Methods: Parental F0 fish were exposed to 1.0 μM BPA or control (0.1% DMSO, v/v) for 7 days. Eggs (F1) were collected and kept in control medium until 4.5 or 120 h post fertilization (hpf). RNA sequencing (RNA-seq) was conducted on embryos and larvae, to discover differentially expressed genes (DEGs), and then KEGG pathway, GO enrichment and GSEA were performed to interpret functional ontology. Histopathology was performed to explore the morphological and structural alterations in liver tissues of zebrafish larvae (120 hpf) after parental BPA exposure., Results: Parental BPA exposure induced global transcriptomic changes in zebrafish embryos and larvae. For embryos, epigenetic regulation genes were decidedly affected, highlighted epigenotoxicity might involve in the transgenerational effects during embryogenesis and early development. By further investigation on its delayed effects, our RNA-Seq data of larvae suggested ROS metabolic process, apoptosis, p53 and MAPK signaling pathway were concentrated, indicating defensive cellular processes still involved in protecting against BPA toxicity. Furthermore, parental BPA-treated larvae manifested hepatic injury by histopathological analysis., Conclusions: Parental BPA exposure led to global transcriptomic changes involved in epigenetic regulation, oxidative stress, apoptosis and DNA damage of offspring. These findings advanced the field of the parental-mediated subsequent generational toxic effects of BPA., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: Exposure to polychlorinated biphenyls (PCBs) has been shown to influence expression of some biomarkers that are predictive/prognostic for breast cancer. Therefore, our study was conducted to further investigating associations of different functional PCBs in adipose tissue with breast cancer prognostic biomarkers., Methods: Two hundred and five breast cancer patients were recruited in Shantou, China. Breast adipose tissues were collected during their resection surgery and levels of 7 PCB congeners were analyzed by gas chromatography-mass spectrometry (GC-MS). The PCB congeners were divided into 4 groups according to structure-activity. Socio-demographic, clinical and pathological information were obtained from questionnaire and digital medical records. Odds ratios (ORs) for associations between prognostic biomarkers and PCB levels (tertile 3 [T3], tertile 2 [T2] vs. tertile 1) were estimated from logistic regression models., Results: Most PCB congeners were detectable, with a highest level (22.06 ng/g lipid) of PCB153. As for estrogenic PCBs, increased PCB52 exposure was positively associated with PR expression (OR T2  = 2.36, P trend  = 0.054), but higher PCB101 level was negatively associated with HER-2 (OR T3  = 0.24, P trend  = 0.029) and tumor size (OR = 0.43). Limited dioxin-like PCB138 exposure was positively associated with ER (OR T2  = 3.23, OR T3  = 3.77, P trend  = 0.047) but negatively with Top-IIα expression (OR T2  = 0.35, OR T3  = 0.28, P trend  = 0.080). Higher PCB153 (CYP inducer) level was negatively associated with ER (OR T2  = 0.32, OR T3  = 0.19, P trend  = 0.038) but positively with Ki-67 expression (OR T2  = 1.43, OR T3  = 3.60, P trend  = 0.055). Higher neurotoxic PCB28 was positively associated with HER-2 (OR T3  = 5.43, P trend  = 0.006) and tumor size (OR = 2.37). Moreover, total PCBs exposure was positively associated with VEGF-C (OR T2  = 76.91, OR T3  = 97.96, P trend  = 0.041) and tumor metastasis (OR = 2.25)., Conclusions: Different functional PCB congeners have different associations (both positive and negative) with breast cancer prognostic biomarkers, as well as tumor classification stage. Therefore, the development and aggressiveness of breast cancer may depend upon exposure to specific structure-activity of PCBs., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The large-batch application of lithium ion batteries leads to the mass production of spent batteries. So the enhancement of disposal ability of spent lithium ion batteries is becoming very urgent. This study proposes an integrated process to handle bulk spent lithium manganese (LiMn 2 O 4 ) batteries to in situ recycle high value-added products without any additives. By mechanical separation, the mixed electrode materials mainly including binder, graphite and LiMn 2 O 4 are firstly obtained from spent batteries. Then, the reaction characteristics for the oxygen-free roasting of mixed electrode materials are analyzed. And the results show that mixed electrode materials can be in situ converted into manganese oxide (MnO) and lithium carbonate (Li 2 CO 3 ) at 1073K for 45min. In this process, the binder is evaporated and decomposed into gaseous products which can be collected to avoid disposal cost. Finally, 91.30% of Li resource as Li 2 CO 3 is leached from roasted powders by water and then high value-added Li 2 CO 3 crystals are further gained by evaporating the filter liquid. The filter residues are burned in air to remove the graphite and the final residues as manganous-manganic oxide (Mn 3 O 4 ) is obtained., (Copyright © 2017 Elsevier B.V. All rights reserved.)