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Lead is classified to be one of the top heavy metal pollutants in China. The corresponding environmental issues especially during the management of spent lead-acid battery have already caused significant public awareness and concern. This research gives a brief overview on the recycling situation based on an investigation of the lead industry in China and also the development of technologies for spent lead-acid batteries. The main principles and research focuses of different technologies including pyrometallurgy, hydrometallurgy and greener technologies are summarized and compared. Subsequently, the circulability of lead based on the entire life cycle analyses of lead-acid battery is calculated. By considering different recycling schemes, the recycling situation of spent lead-acid battery in China can be understood semi-quantitatively. According to this research, 30% of the primary lead production can be shut down that the lead production can still ensure consecutive life cycle operation of lead-acid battery, if proper management of the spent lead-acid battery is implemented according to current lead industry situation in China. This research provides a methodology on the view of lead circulability in the whole life cycle of a specific product and is aiming to contribute more quantitative guidelines for efficient organization of lead industry in China. [ABSTRACT FROM AUTHOR]

Enhancing the level of water use and alleviating the constraints of water shortage on economic and social development are powerful supports to realize the harmonious balance of water and economic society. In this study, the data envelopment analysis (DEA) window analysis method is applied to the study of water use level, and the SBM-DEA model (slack based measure, SBM) is combined to explore the spatial and temporal evolution characteristics of composite water use index (CWUI) in nine provinces from 2012 to 2018. The Malmquist index model is used to decompose the intrinsic causes of total factor productivity (TFP) changes, and the spatial matching degree calculation method is applied to study the matching degree between CWUI and economic and social development levels (E-SDL). The results showed that: (1) the overall trend of CWUI in the nine provinces from 2012 to 2018 was increasing, with significant spatial variability in water use levels; (2) the improvement of TFP of water in the nine provinces was mainly driven by technological change (TC), and the main factor limiting the improvement of TFP of water was technical efficiency change (EC); (3) E-SDL of the nine provinces showed an increasing trend, with the spatial distribution characteristics of decreasing E-SDL of the downstream, midstream and upstream provinces in sequence; (4) the degree of matching between CWUI and E-SDL shows strong regional differences, with different types of matching. [ABSTRACT FROM AUTHOR]

In recent years, Chinese environmental authorities have expressed interest in the use of Tradable Discharge Permits (TDP) as a regulatory instrument to control pollutant emissions. Environmental professionals still have not had enough experience however, in designing and managing TDP systems, especially for non-uniformly dispersed pollutants. As an empirical study, this paper proposes an inter-zonal TDP system and analyzes its effectiveness in cost saving and environmental protection for reducing water pollutant COD (Chemical oxygen demand) in Tianjin, China. Zonal permit system (ZPS) and emission permit system (EPS) are discussed for comparison. The inter-zonal TDP System is demonstrated to improve cost efficiency by allowing permit trades between zones, as long as water quality constraints are satisfied. The transactions are assumed to proceed in a multilateral sequential way and are simulated with a circularly running linear programming (LP) model. The simulation of permit transactions among 20 firms shows that to reach the same COD removal target, ZPS, inter-zonal TDP system, and EPS lowered the total reduction cost by 12.8%, 14.6%, and 15.8%, respectively. EPS, however, brought about "hot spots" problem. Finally, the transaction costs and sensitivity of the three TDP systems to changes in both COD reduction rate and the initial permit allocation are discussed, and policy implications are addressed. [ABSTRACT FROM AUTHOR]

With the rapid development of the lithium-ion battery (LIB) industry, the demand for core valuable elements in LIB has increased dramatically. A safe supply of corresponding metals is crucial to ensure the industry's sustainability. However, quantitative evaluation to reveal the supply risk including criticality of LIBs in China is still not available. In this regard, criticality analysis was carried out to identify the importance of a specific metal in the current LIBs supply chain of raw materials. Subsequently, a comprehensive methodology to evaluate supply sustainability is established in this research by considering the combined effects of material supply, economic fluctuations, and technology innovation in the time frame from 2015 to 2030. An integrated index called Chinese supply resilience is introduced, indicating that a low Chinese supply resilience has a high possibility of supply shortage of the corresponding metal while a high resilience level represents minor supply risk. The results show that insufficient material supply has already induced a severe shortage for lithium (Li) and cobalt (Co). Specifically, Chinese supply resilience of lithium moves from the threshold to the low resilience zone, whereas that for cobalt remains in the low area, both implying a high risk of supply shortage. Furthermore, three appropriate mitigation measures, that is, recycling of spent LIBs, substitution of raw materials, and an increase in domestic raw materials production are considered. Recycling demonstrates the most effective solution to alleviate the potential supply risk of corresponding materials. With this research, it may promote management efficiency on end-of-life LIBs for policy makers. Image 1 • The index of Chinese supply resilience is used to evaluate supply risk of materials. • Supply resilience for Li moves from the threshold to the low-resilience zone. • Supply resilience for Co remains in the low-resilience zone. • Effect of material supply, economy and technology innovation is analyzed. • Scenario analysis considering recycling, substitution and production is conducted. [ABSTRACT FROM AUTHOR]

Chinese steel industry faces increasing pressure to reduce water consumption and wastewater impact. To perform the optimization of steel production process from the perspective of water use, this work describes a new superstructure-based water network optimization model using typical steel park as our study use. The water systems at different scales ( e.g. unit-scale, plant-scale and park-scale) in the water network and their interactions are modeled for optimization. To construct the optimization model: 1) All types of unit-scale typical water systems in the park are identified, and short-cut unit models are developed as the basic elements for network superstructure; 2) Intra- and inter-plant superstructures are further established to describe potential configurations of the water network at plant-scale and park-scale respectively; 3) Built up on the element models and superstructures, a Mixed Integer Non-Linear Programming model using total annual cost as objective is set up to investigate potentials for water network optimization in a steel park. To illustrate its applicability and effectiveness, an industrial case study is carried out, in which two schemes are illustrated, one scheme (termed as scheme A) considering only indirect integration between plants, the other (termed as scheme B) considering both direct and indirect integration strategy (mixed integration). In scheme A, due to the higher water efficiency and optimal configuration in the case study, the freshwater consumption and total annual cost are reduced by 22% and 21% respectively. Scheme B shows 23% savings in total annual cost, while the reduction of freshwater consumption keeps unchanged. Besides, the information about the integration strategies of all scales ( e.g. unit-, plant- and park-scale) can all be obtained, which is valuable for decision-making. [ABSTRACT FROM AUTHOR]

This study investigated a combined low-thermal and CaO 2 pretreatment to enhance the volatile fatty acid (VFA) production from waste activated sludge (WAS). The fermentative product was added to a sequencing batch reactor (SBR) as an external carbon source to enhance nitrogen removal. The results showed that the combined pretreatment improved WAS solubilization, releasing more biodegradable substrates, such as proteins and polysaccharides, from TB-EPS to LB-EPS and S-EPS. The maximum VFA production of 3529 ± 188 mg COD/L was obtained in the combined pretreatment (0.2 g CaO 2 /g VS + 70 °C for 60 min), which was 2.1 and 1.4-fold of that obtained from the sole low-thermal pretreatment and the control test, respectively. Consequently, when the fermentative liquid was added as an external denitrification carbon source, the effluent total nitrogen decreased to Class A of the discharge standard for pollutants in rural wastewater treatment plants in most areas of China. [Display omitted] [ABSTRACT FROM AUTHOR]

Proper understanding and evaluation of a metal production process is crucial for its further optimization. Economic evaluation is frequently used to estimate the practicality of a specific process based on the product life cycle assessment. However, it encounters difficulties to identify the importance of materials efficiency coupling with pollution control during evaluation on the effectiveness of process optimization. In this research, a factor defining the material recirculation is introduced to economic evaluation. Typical vanadium oxide production processes in China were evaluated by the economic evaluation model considering the whole production process, through defining a range of parameters, i.e., the materials cost, water cost, energy cost, waste treatment cost and auxiliary cost. Three V 2 O 5 production processes are analyzed and compared to each other. The production process of high purity V 2 O 5 has the best cost-effective products with high purity, the simplest production, the highest materials efficiency and the lowest cost for waste treatment. It is noticed that materials efficiency tends to be inversely proportional to waste treatment cost. Under comprehensive environmental assessment, proper pollutant control improves material recirculation percentage and reduces the expense for waste treatment which is an important aspect of economic evaluation. With this research, an optimization scheme is illustrated for the economic evaluation of typical metal production process which may provide guidance to industrial factories to optimize relevant production processes. Image 1 • A material recirculation factor is introduced to economic evaluation model. • Typical vanadium oxide production processes were evaluated. • Comprehensive environmental assessment analyzed environmental impact of the waste. • The high recirculation percentage can effectively decrease the total cost. [ABSTRACT FROM AUTHOR]

Manufacturing of chips and their associated products is a complex and multi-step process where evaluation on the materials and environmental efficiencies is difficult, and a typical life cycle assessment cannot fulfil the role. In this research, a multiple evaluation scheme in view of green manufacturing is developed by combining critical evaluation, mass flow analysis and environmental impact assessment, in order to define the green degree for chips and lamps production of light-emitting diodes (LED). Mass and energy flow are identified with a subsequent critical evaluation for the whole process to determine the importance of 160 kinds of substances, energies, waters, pollutants, and procedures. In 96 kinds of substances, the organics and metal contained substances have higher criticality and accounting for 33.49% and 56.54%, respectively. To understand the effects of critical pollutants, a comprehensive environmental assessment factor (CEA) is then implemented, and waste water in chip preparation section has larger CEA value. As a result, ten green manufacturing level is defined through a grading decision function, and LED filament lamp reaches a higher manufacturing level than surface-mounted device (SMD) based LED lamp. By defining three scenarios, the manufacturing level of largest environmental effect scenarios is 7, reflecting the CEA of the pollutants is the most critical parameter. With this evaluation system, the green manufacturing level of one manufacturing section or different manufacturing processes can be evaluated, which can guide the identification and classification of LED lamps and other products. [Display omitted] • A multiple evaluation scheme in view of green manufacturing was developed. • Critical evaluation, mass flow analysis and environmental assessment were combined. • The green manufacturing level of LED filament lamp is higher than SMD LED lamp. • Environmental impact of the pollutants largely affects the green level of LED lamp. [ABSTRACT FROM AUTHOR]

To determine the priority control sources, an approach was proposed to evaluate the source-specific contribution to health risks from inhaling PM 2.5 -bound heavy metals (PBHMs). A total of 482 daily PM 2.5 samples were collected from urban and suburban areas of Beijing, China, between 2018 and 2019. In addition to the PMF-PSCF model, a Pb isotopic IsoSource model was built for more reliable source apportionment. By using the comprehensive indicator of disability-adjusted life years (DALYs), carcinogenic and noncarcinogenic health risks could be compared on a unified scale. The study found that the annual average concentrations of the total PBHMs were significantly higher in suburban areas than in urban areas, with significantly higher concentrations during the heating season than during the nonheating season. Comprehensive dust accounted for the largest contribution to the concentration of PBHMs, while coal combustion contributed the most to the DALYs associated with PBHMs. These results suggest that prioritizing the control of coal combustion could effectively reduce the disease burden associated with PBHMs, leading to notable public health benefits., 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 © 2024 Elsevier Ltd. All rights reserved.)

PM 2.5 is the main component of haze, and PM 2.5 -bound heavy metals (PBHMs) can induce various toxic effects via inhalation. However, comprehensive macroanalyses on large scales are still lacking. In this study, we compiled a substantial dataset consisting of the concentrations of eight PBHMs, including As, Cd, Cr, Cu, Mn, Ni, Pb and Zn, across different cities in China. To improve prediction accuracy, we enhanced the traditional land-use regression (LUR) model by incorporating emission source-related variables and employing the best-fitted machine-learning algorithm, which was applied to predict PBHM concentrations, analyze geographical patterns and assess the health risks associated with metals under different PM 2.5 control targets. Our model exhibited excellent performance in predicting the concentrations of PBHMs, with predicted values closely matching measured values. Noncarcinogenic risks exist in 99.4% of the estimated regions, and the carcinogenic risks in all studied regions of the country are within an acceptable range (1 × 10 -5 -1 × 10 -6 ). In densely populated areas such as Henan, Shandong, and Sichuan, it is imperative to control the concentration of PBHMs to reduce the number of patients with cancer. Controlling PM 2.5 effectively decreases both carcinogenic and noncarcinogenic health risks associated with PBHMs, but still exceed acceptable risk level, suggesting that other important emission sources should be given attention., 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 Ltd. All rights reserved.)

To clarify the spatial patterns of disease burden caused by toxic metals in fine particulate matter (PM 2.5 ) across China, annual concentration levels of typical toxic metals in PM 2.5 over 60 cities of China were retrieved. Then, potential years of life lost (PYLL) attributable to toxic metal (As, Cd, Cr (VI), Mn, and Ni) exposure was calculated from health risk assessments and lifetable estimates. The results show that Cr(VI) and As were the most polluted metals and greatly exceeded the recommended annual values in the National Ambient Air Quality Standard of China. PYLL for each death (mean ± standard deviation) of 19.8 ± 4.5 years was observed for lung cancer, followed closely by COPD and pneumonia. Furthermore, the PYLL rate (years per 100,000 people) attributable to exposure to these toxic metals was 457 (male: 505, female: 402) years for different cities; therein, Cr(VI) contributed the highest PYLL among these toxic metals, with a proportion of 72.7% (male: 75.3%, female: 69.5%), followed by As of 16.4% (male: 13.8%, female: 19.8%). The concentration level and PYLL both showed large spatial variability, of which the top-ranking cities were observed to be affected by well-developed metal-related industries and coal-powered industrial sectors., 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 © 2021 Elsevier B.V. All rights reserved.)

Daily PM 2.5 was collected in the periods before, during and after the Chinese Spring Festival (CSF) in both 2016 and 2018 to clarify the annual variation in the concentrations and health risks of toxic metals under different firework/firecracker (FF) management strategies. PM 2.5 and bound metals all decreased during the CSF from 2016 to 2018. According to relative abundance analysis, toxic metals, i.e., Ba, Pb, Cu and Cr, showed obvious peak concentrations and abundance levels on intensive FF burning days, i.e., New Year's Eve, Chinese New Year and the Lunar Festival. In both CSF periods, three sources of toxic metals, namely, FF burning, coal combustion, and resuspended dust and vehicle emissions, were identified by positive matrix factorization (PMF). Among them, the mass contribution of FF decreased from 0.83 μg m -3 (11%) in the 2016 CSF to 0.23 μg m -3 (9.0%) in the 2018 CSF. The FF-attributed noncancer and cancer risks due to metals for residents under long-term exposure were 0.02 (19.9%) and 1.76 × 10 -7 (17.9%) in the 2016 CSF and 0.01 (20.2%) and 8.59 × 10 -8 (14.7%) in the 2018 CSF. Although a policy shift from "restriction" to "prohibition" regarding FF has indeed decreased toxic metal concentrations and health risk, Cr(VI) and Ba should be examined more closely in the future because they have become dominant contributors to cancer risk and noncancer risk, respectively., (Copyright © 2019 Elsevier Inc. All rights reserved.)

PM 2.5 -bound PAHs are ubiquitous in urban atmospheres and are characterized as carcinogenic, teratogenic and mutagenic upon inhalation. A total of 218 daily PM 2.5 samples were collected during one year in the urban district of Beijing, China. Analysis showed that the annual mean concentration of total PAHs (TPAHs) was 66.2 ng/m 3 , with benzo(a)pyrene (BaP) accounting for 12.4%. High-molecular-weight (HMW, 4-6 rings) PAHs were the dominant components. Seasonal TPAH concentrations decreased in the order of heating season (156 ng/m 3 ) > autumn (20.4 ng/m 3 ) > spring (16.0 ng/m 3 ) > summer (12.5 ng/m 3 ) and were related to meteorological conditions and source emission intensity. The source-attributed mass contribution and source regions of three sources (i.e., (1) vehicle emissions; (2) coal combustion; and (3) petroleum volatilization, natural gas and biomass combustion) were identified by integrating the positive matrix factorization (PMF), potential source contribution function (PSCF) and conditional probability function (CPF). Vehicle emissions contributed the most mass (54.6%), followed by coal combustion (29.8%), on an annual basis. Combined with actual regional emissions, vehicle emissions were mainly derived from local sources, while coal combustion mainly came from regional transport from surrounding areas. Vehicle emissions and coal combustion have much higher mass contributions in the heating season. The source-attributed cancer risk was further evaluated based on source mass contribution and inhalation unit risk. Vehicle emissions contributed the largest risk (2.8 × 10 -6 , accounting for 71%) as a result of 30 years of exposure for local residents, exceeding the acceptable level (10 -6 ). The heating season showed the most risk, especially in response to vehicle emissions and coal combustion. Overall, the source-attributed cancer risk was regarded as the better index for the development of a control strategy of PM 2.5 -bound PAHs for protecting residents. Based on this index, priority control sources in each season were identified to supply a more effective management solution., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Source-specific health risks of PM 2.5 -bound metals were analyzed for emission control by integrating source apportionment with health risk assessments of residents affected via inhalation pathways. A total of 218 daily PM 2.5 samples were collected in 2016 in the central urban district of Beijing, China. Analyses showed that the mean annual concentrations of total heavy metals (THMs) and PM 2.5 were 0.39 and 104.37 μg m -3 , respectively. The heating season had significantly higher concentrations of THMs and PM 2.5 (0.61, 134 μg m -3 ) than the non-heating season (0.27, 88.1 μg m -3 ) (p < 0.05). Among all metals, arsenic had the largest incremental cancer risk of 7.04 × 10 -6 . Six sources were identified by positive matrix factorization combined with conditional probability function and potential source contribution function analyses. The order of contribution to PM 2.5 -bound metal concentrations was resuspended dust (61.0%), traffic emission (16.3%), Cu-related industry (14.1%), coal combustion (3.7%), Cr-related industry (3.4%), and fuel oil combustion (1.6%). During the heating season, the contribution of coal combustion decreased slightly, which may have been due to the countermeasure of substituting coal for gas or electric heat in 2016. However, in terms of cancer risk contribution, coal combustion was the top contributor in both heating (3.5 × 10 -6 , 51.6%) and non-heating (2.7 × 10 -6 , 59.6%) seasons due to high attributable contents of the toxic metals, As, Cd and Pb. The Cr-related and Cu-related industries were the next controlled sources in the heating and non-heating seasons, respectively. Thus, these sources should receive priority in the development of control measures., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Giant cell tumors of the distal radius are challenging for surgeons because they are associated with high recurrence rates and poor functional outcomes. Between June 2005 and October 2015, patients with primary giant cell tumors of the distal radius were recruited from seven orthopedic centers in China. The patients' clinical features and demographic characteristics were obtained from medical records and reviewed retrospectively. Overall, 48 cases of giant cell tumors of the distal radius were assessed in this study. These patients were more likely to be between 20 and 40 years of age, to have a Campanacci grade of III, and to undergo a surgical style of resection. The prevalence of pathological fractures was 12.5% overall (20.0% in men and 4.3% in women). The prevalence of local recurrence was 30.0% overall (38.1% in men and 21.1% in women) during the average follow-up period of 62.5 months, with a pulmonary metastasis rate of 5.0%. Giant cell tumors of the distal radius were predominant in men and were more likely to recur locally than around the knee. These findings suggest that it is crucial to evaluate the optimal surgical approach for balancing local recurrence control and functional outcomes to reduce the disease burden.

Background: We evaluated the relationship of human papillomavirus (HPV) and Epstein-Barr virus (EBV) with race in endemic and nonendemic cohorts of patients with nasopharyngeal carcinoma (NPC), and with smoking status in the nonendemic cohort., Methods: Tissue microarrays (TMAs) were constructed using samples from 86 patients treated in southern China and 108 patients from Stanford, California. TMAs were stained with p16, HPV in situ hybridization (ISH), and EBV ISH. Polymerase chain reaction (PCR) was used to confirm EBV(-) cases and HPV status in p16(+) cases. Survival data was available for the Stanford cohort only., Results: No HPV(+) cases were detected in the Chinese cohort. In the Stanford cohort, 5 of 11 EBV(-) cases harbored HPV-16, 10 of 10 occurred in whites, and 8 of 11 were smokers. Patients with EBV(-) NPC also showed a trend toward worse survival., Conclusion: EBV(-) NPC shows an association with the presence of HPV, white race, and smoking. In contrast, EBV(-) NPC shows no association with HPV in the endemic cohort., (Copyright © 2013 Wiley Periodicals, Inc.)

The current study focused on the influences of various pretreatments, including alkaline, ultrasonic and thermal pretreatments on biological sulfate reduction with waste activated sludge (WAS) as sole electron donor. Our results showed that thermal and ultrasonic pretreatments increased the sulfate reduction percentage by 14.8% and 7.1%, respectively, compared with experiment with raw WAS, while alkaline pretreatment decreased the sulfate reduction percentage by 46%. By analyzing the WAS structure, particle size distribution, organic component, and enzyme activity after different pretreatments, we studied the effects of these pretreatments on WAS as well as on the mechanisms of how biological sulfate reduction was affected. The reduction of WAS and variation of WAS structure in the process of sulfate reduction were investigated. Our results showed that biosulfidogenesis was an efficient method of diminishing WAS, and various pretreatments could enhance the reduction efficiency of volatile solid in the WAS., (2010 Elsevier B.V. All rights reserved.)

As the consumption of Puerh tea is booming because of its multiple health-promoting effects, the possible health risks resulting from long-term exposure to metals contained in this tea need to be evaluated. To assess the human risk associated with drinking Puerh tea, concentrations of aluminium, lead, cadmium, mercury, zinc, copper and arsenic were determined in samples of Puerh tea, tea leaves from the plants, and planted soil collected from the Yunnan province, China. Site-specific exposure parameters such as body weight and consumption rate of Puerh tea were investigated in Kunming and Puer cities using face-to-face surveys. Health risks were evaluated for the inhabitants of Kunming and Puer cities by gender and by age groups. Although the Puerh tea plant easily absorbs aluminium from soil, the concentrations of Al and six other elements in Puerh tea were all far below the safety concentration limits of China. Both the HQ (Hazard Quotient) values for single elements and the HI (Hazard Index) value for all seven elements were far below one, indicating no non-carcinogenic risks from these seven elements for inhabitants of Kunming and Puer under the current consumption rates of Puerh tea. However, probabilistic estimation of carcinogenic risk shows that the 95th percentile carcinogenic rate of arsenic in Puerh tea approaches the accepted risk level of 10(-4) for the highest exposure group. Therefore, the arsenic in Puerh tea is of concern., (Copyright 2010 Elsevier B.V. All rights reserved.)

Contamination of soil and agricultural products by heavy metals resulting from rapid industrial development has caused major concern. In this study, we investigated heavy metal (Cu, Zn, Pb, Cr, Hg and Cd) concentrations in rice and garden vegetables, as well as in cultivated soils, in a rural-industrial developed region in southern Jiangsu, China, and estimated the potential health risks of metals to the inhabitants via consumption of locally produced rice and garden vegetables. A questionnaire-based survey on dietary consumption rates of foodstuffs showed that rice and vegetables accounted for 64% of total foodstuffs consumed, and over 60% of rice and vegetables were grown in the local region. Average concentrations of Cr, Cu, Zn, Cd, Hg and Pb were 0.75, 2.64, 12.00, 0.014, 0.006 and 0.054 mg/kg dw (dry weight) in rice and were 0.67, 1.18, 4.34, 0.011, 0.002 and 0.058 mg/kg fw (fresh weight) in garden vegetables, respectively. These values were all below the maximum allowable concentration in food in China except for Cr in vegetables. Leafy vegetables had higher metal concentrations than solanaceae vegetables. Average daily intake of Cr, Cu, Zn, Cd, Hg and Pb through the consumption of rice and garden vegetables were 5.66, 16.90, 74.21, 0.10, 0.04 and 0.43 microg/(kg x day), respectively. Although Hazard Quotient values of individual metals were all lower than 1, when all six metal intakes via self-planted rice and garden vegetables were combined, the Hazard Index value was close to 1. Potential health risks from exposure to heavy metals in self-planted rice and garden vegetables need more attention.