Carbon emissions in China's steel industry from a life cycle perspective: Carbon footprint insights.

China is the most important steel producer in the world, and its steel industry is one of the most carbon-intensive industries in China. Consequently, research on carbon emissions from the steel industry is crucial for China to achieve carbon neutrality and meet its sustainable global development goals. We constructed a carbon dioxide (CO2) emission model for China's iron and steel industry from a life cycle perspective, conducted an empirical analysis based on data from 2019, and calculated the CO2 emissions of the industry throughout its life cycle. Key emission reduction factors were identified using sensitivity analysis. The results demonstrated that the CO2 emission intensity of the steel industry was 2.33 ton CO2/ton, and the production and manufacturing stages were the main sources of CO2 emissions, accounting for 89.84% of the total steel life-cycle emissions. Notably, fossil fuel combustion had the highest sensitivity to steel CO2 emissions, with a sensitivity coefficient of 0.68, reducing the amount of fossil fuel combustion by 20% and carbon emissions by 13.60%. The sensitivities of power structure optimization and scrap consumption were similar, while that of the transportation structure adjustment was the lowest, with a sensitivity coefficient of less than 0.1. Given the current strategic goals of peak carbon and carbon neutrality, it is in the best interest of the Chinese government to actively promote energy-saving and low-carbon technologies, increase the ratio of scrap steel to steelmaking, and build a new power system.

Reversibly crosslinked polyurethane fibres from sugar-based 5-chloromethylfurfural: Synthesis, fibre-spinning and fibre-to-fibre recycling.

The development of recyclable crosslinked thermosetting fibres is a challenging research topic. In the present work, we have designed and synthesized polyurethane fibres from fructose-derived 5-chloromethylfurfural (CMF) and lignin-derived monomeric phenols. The greenhouse gas emissions associated with the production of CMF showed comparable results to that of 5-hydroxymethylfurfural (HMF), a high potential sugar-based platform molecule. The wet-spun biobased polyurethane fibres produced could be conveniently crosslinked using Diels-Alder chemistry to effectively enhance the glass transition temperature and mechanical properties. At a mildly elevated temperature (140 °C), the chemically crosslinked fibres could be effectively de-crosslinked, which enabled complete separation from a mixture with poly(ethylene terephthalate) (PET) and cotton fibres. These results outline a potential strategy to design and fabricate new biobased fibres with reversible crosslinking, which may enable fibre-to-fibre recycling.

A comprehensive review on integrating sustainable practices and circular economy principles in concrete industry.

This comprehensive review explores the integration of circular economy principles into the concrete industry, emphasizing their role in enhancing sustainability and resource efficiency. It covers the fundamental concepts of circular economy and examines the application of Life Cycle Assessment (LCA) in evaluating the environmental impacts of concrete production. The review highlights innovative strategies for recycling, reuse, waste reduction, and resource optimisation, showcasing how these approaches can transform concrete production practices. It also addresses the policy considerations, economic implications, and societal impacts associated with adopting circular economy practices. Furthermore, the review investigates recent technological advancements in circular concrete production, including self-healing concrete and 3D printing. By summarizing these findings and offering practical recommendations, the review aims to support the industry in transitioning towards more sustainable practices. This detailed analysis provides valuable insights into the benefits and challenges of circular economy adoption, helping stakeholders make informed decisions for a greener concrete sector.

Comparative life cycle assessment of non-thermal plasma for the removal of pharmaceuticals from wastewater.

Wastewater effluents are a continuous source of pharmaceuticals in water bodies, which pose a serious environmental threat to aquatic ecosystems. This work provides a comprehensive technical, environmental and cost assessments of different advanced quaternary treatments for wastewater effluents, with special focus on novel Non-Thermal Plasma technology. For this porpouse Non-Thermal Plasma, Sand Filtration + Ozonation, Ultrafiltration, Ultrafiltration + Nanofiltration and Ultrafiltration + Reverse Osmosis technologies were compared with UV disinfection-based technology. This work applies the Life Cycle Analysis tool for the impact environmental assessment using both ReciPE 2016(H) method and, for a more detailed analysis of the contribution of pharmaceuticals to freshwater ecotoxicity category of impact, the USETOX method, which was integrated with 7 new characterisation factors. The results obtained showed overall removal efficiency of pharmaceuticals always higher than 80%, with performances in descending order of Ultrafiltration + Reverse Osmosis > Sand Filtration + Ozonation > Ultrafiltration + Nanofiltration > Non-Thermal Plasma, being Sand Filtration + Ultraviolet disinfection and standalone Ultrafiltration comparatively not suitable for pharmaceuticals removal. Regarding the target pharmaceuticals proposed on the EU Directive 271/91 revision, the Non-Thermal Plasma perform better towards venlafaxine than Sand Filtration + Ozonation, and towards diclofenac and carbamazepine than Ultrafiltration + Nanofiltration. Ultrafiltration + Nanofiltration and Non-Thermal Plasma showed better environmental performance than Sand Filtration + Ozonation and Ultrafiltration + Reverse Osmosis in 7 out of 18 categories of impact (ReciPe method), with Ultrafiltration + Nanofiltration being more advantageous than Non-Thermal Plasma in human and ecotoxicity-related categories of impact, and Non-Thermal Plasma more advantageous in Global Warming, Fossil Resource Scarcity, and Fine Particulate Matter Formation. Regrading Freshwater Ecotoxicity (USEtox method), the quaternary treatment configuration and its energy demand affect the Freshwater final value of impact more than the presence of pharmaceuticals. Under the conditions tested, the Non-Thermal Plasma provided the lower OPEX (0.24 € m-3) than other tested technologies, showing an interesting compromise between pharmaceuticals removal efficiency, environmental impacts, and economic operational cost.

Bio-organic substitution in tobacco (Nicotiana tabacum L) cultivation: Optimum strategy to lower carbon footprint and boost net ecosystem economic benefit.

The partial substitution of organic manure for chemical nitrogen fertilizers, known as organic substitution, is widely regarded as a cleaner and more sustainable production strategy. However, few studies have quantified greenhouse gas emissions, product income and net ecosystem economic benefit (NEEB) using a life cycle assessment (LCA) approach, particularly for typical tobacco (Nicotiana tabacum L.) production. Here, we quantified the yield and quality of a typical tobacco production in Qujing, Yunnan, China, through field experiments and calculated its carbon footprint and NEEB using the LCA approach. Four organic substitution strategies were established with equal nitrogen inputs, including synthesized chemical fertilizer (SN), farmyard organic manure (NF), commercial organic manure (NC), and bio-organic (Trichoderma viride Pers.) manure (NT), each substituting 15% of synthesized nitrogen fertilizer. Compared to the SN strategy, the NT strategy significantly increased yield and income by 10.3% and 9.6%, respectively. In contrast, the NF strategy significantly reduced income, while the NC strategy showed no significant difference. Both the NC and NT strategies significantly reduced N2O cumulative emissions (by 15.9% and 8.0%, respectively), increased δSOC (by 38.4% and 15.0%, respectively), and decreased carbon footprint compared to the SN strategy. However, the NF strategy significantly increased the income-scaled carbon footprint, even though it also notably reduced N2O cumulative emissions (by 22.6%) and increased δSOC (by 7.9%). The NT strategy achieved a win-win scenario of low environmental risk and high economic returns of tobacco production with significantly increased NEEB (by 10.6%) compared to the SN strategy (37.60 × 103 CNY yr-1). This suggests that the bio-organic Trichoderma manure substituting 15% synthesized nitrogen fertilizer is the best organic substitution strategy for sustainable tobacco production.

Optimizing solarized desalination unit through the implementation of 4-step MED method using energy, exergy, economic and environmental analysis.

The consumption of thermal energy in thermal desalination plants leads to a higher price for the fresh water they produce compared to other methods. By utilizing optimization techniques, it is possible to lower both energy consumption and price. The focus of this paper is on optimizing a solarized desalination unit through the implementation of the 4-step MED method with a PTC collector. To achieve this objective, the NSGA II algorithm was implemented in MATLAB using a function for optimization. This algorithm is known for its cost-effectiveness and high energy efficiency. According to the results, there has been an improvement in the fresh water flow rate, desalination efficiency, and GOR, with values reaching 126.87, 53.6%, and 3.66 respectively, compared to the previous values of 116.5, 49.21%, and 3.32. In the ideal condition, the power generated is 6089 kW, priced at 3.28 cents per kilowatt, and the cost of producing fresh water is 8.49 dollars per cubic meter, which decreases as the process lifespan increases. Solar collectors and thermal tanks account for the largest portion (64%) of exergy destruction, as indicated by the exergy analysis. Optimization of the process has led to energy and exergy efficiencies of 59.8% and 58%, respectively, representing a notable enhancement of around 10% in the system's lifespan. The optimal mode also includes the completion of the sensitivity analysis. The process was subjected to LCA analysis, and the results indicated that the largest impact is on human health, with the collectors and thermal storage tanks being responsible for most of the pollution. As a result, the optimized process has delivered outstanding results while also being environmentally conscious.

Assessing environmental sustainability of substitute feeding formulas for gilthead seabream (Sparus aurata) using Life Cycle Assessment.

The rise in fish and seafood consumption driven by aquaculture comes with its share of challenges and controversies, notably the need for expanded feed production. The use of fishmeal and fish oil to raise carnivorous fish has caused environmental problems, including ecosystem imbalance and habitat destruction, as well as ethical issues like fishing forage fish for feed instead of human consumption. Thus, the industry has been actively pursuing alternative feed ingredients to reduce reliance on fish-derived components. This progress in the aquaculture feed sector has made selecting the best feed solution complex across various fronts. This study aims to assess the environmental impacts of three feed formulations, each with different protein sources (poultry by-products, PMB, Tenebrio molitor larvae, TM, or Hermetia illucens larvae, HI), tailored for the gilthead seabream (Sparus aurata), a prized species in European aquaculture. The environmental sustainability of these alternatives was evaluated against benchmarks of fishmeal and fish oil-based feed. Employing a cradle-to-gate approach and a FU of 1 kg of product, the study utilized OpenLCA software supported by the Ecoinvent ® v3.7.1 database. The results focused on the production stages of each ingredient, including logistical and transportation aspects leading up to the final formulation. All alternatives to traditional feed demonstrated either comparable or superior environmental performance (i.e. - 66 % of PMB-f, -33 % of TM-f and - 29 % HI-f kgCO2 eq) with few exceptions for TM-f. This investigation highlighted how integrating innovative ingredients could positively impact the environmental footprint of aquafeed production chains. Furthermore, the main hotspots in the alternative feed formulas life cycles have been identified and viable alternatives for improvement have been proposed, such as selecting different input materials or enhancing energy efficiency. This assessment allows to guide the selection of more environmentally friendly feed formulations before their integration into aquaculture chain processes.

Nutrition support in children with medical complexity and chronic critical illness: A narrative review.

Children with medical complexity (CMC) and children with chronic critical illness (CCI) represent growing populations with high healthcare use and dependence on specialized care, both in the hospital and community setting. Nutrition assessment and delivery represent critical components of addressing the short-term and long-term health needs for these populations across the care continuum. This article provides a framework and reviews existing literature for the assessment of nutrition status and subsequent delivery of nutrition prescriptions in CMC and children with CCI. The specific aims are to (1) describe the epidemiology of health services experience for CMC and children with CCI, with a focus on their nutrition outcomes; (2) detail how to assess their nutrition status and energy requirements; (3) review methods of delivery of the nutrient prescription; (4) introduce perioperative considerations; (5) highlight examples of special populations of CMC and children with CCI; and (6) propose future research initiatives to improve nutrition and overall outcomes for these populations.

Process innovations and circular strategies for closing the water loop in a process industry.

By implementing advanced wastewater treatment technologies coupled with digital tools, high-quality water is produced to be reused within the industry, enhancing process efficiency and closing loops. This paper investigates the impact of three innovation tools (process, circular and digital) in a Solvay chemical plant. Four technologies of the wastewater treatment plant "WAPEREUSE" were deployed, predicting their performance by process modelling and simulation in the PSM Tool. The environmental impact was assessed using Life Cycle Assessment and compared to the impact of the current industrial effluent discharge. The circularity level was assessed through three alternative closed-loop scenarios: (1) conventional treatment and discharge to sea (baseline), (2) conventional and advanced treatment by WAPEREUSE and discharge to sea, (3) conventional and advanced treatment by WAPEREUSE and industrial water reuse through cross-sectorial symbiotic network, where effluents are exchanged among the process industry, municipality and a water utility. Scenario 1 has the lowest pollutants' removal efficiency with environmental footprint of 0.93 mPt/m3. WAPEREUSE technologies decreased COD by 98.3%, TOC by 91.4% and nitrates by 94.5%. Scenario 2 had environmental footprint of 1.12 mPt/m3. The cross-sectorial symbiotic network on the industrial value chain resulted in higher industrial circularity and sustainability level, avoiding effluents discharge. Scenario 3 is selected as the best option with 0.72 mPt per m3, reducing the environmental footprint by 21% and 36% compared to Scenarios 1 and 2, respectively.

Exploring the expanding universe of host-virus interactions mediated by viral RNA.

RNA is a central molecule in RNA virus biology; however, the interactions that it establishes with the host cell are only starting to be elucidated. In recent years, a methodology revolution has dramatically expanded the scope of host-virus interactions involving the viral RNA (vRNA). A second wave of method development has enabled the precise study of these protein-vRNA interactions in a life cycle stage-dependent manner, as well as providing insights into the interactome of specific vRNA species. This review discusses these technical advances and describes the new regulatory mechanisms that have been identified through their use. Among these, we discuss the importance of vRNA in regulating protein function through a process known as riboregulation. We envision that the elucidation of vRNA interactomes will open new avenues of research, including pathways to the discovery of host factors with therapeutic potential against viruses.

Between green hills and green bills: Unveiling the green shades of sustainability and burden shifting through multi-objective optimization in Swiss energy system planning.

The Paris Agreement is the first-ever universally accepted and legally binding agreement on global climate change. It is a bridge between today's and climate-neutrality policies and strategies before the end of the century. Critical to this endeavor is energy system modeling, which, while adept at devising cost-effective carbon-neutral strategies, often overlooks the broader environmental and social implications. This study introduces an innovative methodology that integrates life-cycle impact assessment indicators into energy system modeling, enabling a comprehensive assessment of both economic and environmental outcomes. Focusing on Switzerland's energy system as a case study, the model reveals that optimizing key environomic indicators can lead to significant economic advantages, with system costs potentially decreasing by 15% to 47% by minimizing potential impacts from the current system still operating with fossil technologies to an alternative only relying on renewable and where the impact are mainly related to the construction of the infrastructure. However, a system optimized solely for economic efficiency, despite achieving 63% reduction in carbon footprint compared to 2020, shows a potential risk of burden shift to other environmental issues. The adoption of multi-objective optimization in this approach nuances the exploration of the complex interplay between environomic objectives and technological choices. The results illuminate pathways towards more holistically optimized energy systems, effectively addressing trade-offs across environmental problems and enhancing societal acceptance of the solutions to this century's defining challenge.

Research on the carbon neutralization of hot mix asphalt pavement based on life cycle assessment theory.

The goal of reducing carbon emissions in the field of road engineering has become an important deployment strategy. Based on the life cycle assessment (LCA) theory, the environmental impact assessment and analysis of hot-mix asphalt pavement were carried out in this work on the basis of collecting and investigating the environmental load list data of hot-mix asphalt pavement. According to different life cycle stages, corresponding carbon neutralization schemes were proposed, and the optimal carbon neutralization schemes at different stages were obtained by simulation using queuing theory. The results showed that in the whole life cycle of hot mix asphalt pavement, the construction stage had the highest energy consumption and carbon emissions compared to the other stages, and its global warming potential (GWP) and Chinese abiotic depletion potential (CADP) were also the highest, with the greatest impact on the environment. Compared to other stages, the repair and demolition stage had the smallest contribution to the GWP and CADP evaluation indicators. In the material production stage, the ASRT 5A zeolite adsorbent had the best adsorption effect on carbon dioxide gas. The carbon emissions generated during the production phase of the neutralization material required an ASRT 5A zeolite adsorbent of about 83 kg. Michelia chapensis exhibited the best carbon dioxide purification effect compared to the other three trees during the transportation construction and maintenance disassembly phase. Michelia chapensis required a leaf area of about 28,016 m2 to neutralize the carbon dioxide emissions generated in these two stages.

Environmental and socio-economic evaluation of a groundwater bioremediation technology using social Cost-Benefit Analysis: Application to an in-situ metal(loid) precipitation case study.

Bioremediation can be an alternative or complementary approach to conventional soil and water treatment technologies. Determining the environmental and socio-economic impacts of bioremediation is important but rarely addressed. This work presents a comprehensive sustainability assessment for a specific groundwater bioremediation case study based on In-situ Metal(loid) Precipitation (ISMP) by conducting a social Cost-Benefit Analysis (CBA) using two different approaches: environmental Life Cycle Costing (eLCC) and Impact Pathway Approach (IPA). Externalities are calculated in two ways: i) using Environmental Prices (EP) to monetize Life Cycle Assessment (LCA) results and metal(loid)s removed at field scale, and ii) following the IPA steps to determine the social costs avoided by removing arsenic contamination at full scale. The results show that, in the baseline scenario, the project is not socio-economically viable in both cases as the Net Present Value (NPV) is -129,512.61 € and - 415,185,140 € respectively. Sensitivity and scenario analyses are performed to identify the key parameters and actions needed to reach a positive NPV. For instance, increasing the amount of water treated per year to 90 m3 and assuming a 20 % increase in operation costs and a 60 % increase in construction costs can make the project socio-economically viable at the field scale, while a reduction in the social discount rate from a 4 % to a 2 % can lead to a positive NPV at the full scale. The approaches proposed in this work may be useful for practitioners and policymakers when evaluating the environmental and socio-economic impacts of bioremediation technologies at different scales and regions, as well as human health impacts caused by contaminants at the current legal limits.

Tylvalosin tartrate inhibits the replication stage of the porcine reproductive and respiratory syndrome virus life cycle.

The aetiological agent of porcine reproductive and respiratory syndrome, a deadly disease that affects pigs and seriously jeopardises the global swine industry, is a porcine reproductive and respiratory syndrome virus (PRRSV). Tylvalosin tartrate, which is a macrolide antibiotic, is the active ingredient in Aivlosin. In recent years, tylvalosin tartrate has widely been used to control porcine reproductive and respiratory syndrome in swine herds in China. However, whether tylvalosin tartrate has exerts anti-PRRSV effects remains controversial. In the present study, tylvalosin tartrate exhibited no effect on PRRSV susceptibility but suppressed the replication of PRRSV and the activity of infecting Marc-145 cells. Next, the relationship between the replication cycle of PRRSV and the activity of tylvalosin tartrate was further assessed. Tylvalosin tartrate did not affect the attachment and release stages of PRRSV or act during the internalisation stage of the virus in HuN4; however, contrasting effects were noted for strains CH-1a and SDVD-HN21. Tylvalosin tartrate acted on the replication stage of PRRSV and was not strain-specific in the replication stage of the PRRSV life cycle. The study findings provide an initial clarification of the inhibitory effects of tylvalosin tartrate on PRRSV, providing new insights into the treatment of PRRS.

An MFA-LCA framework for goal-oriented waste management studies: 'Zero Waste to Landfill' strategies for institutions.

Institutions such as university communities can be considered miniature versions of the larger society in which they exist. Nonetheless even though it should be easier to manage waste at an institution, their waste management (WM) programmes are typically lack an overall goal for improving environmental impact and are not optimally structured or operated. In part this is due to a lack of a framework that promotes a goal-oriented WM strategy. For instance, zero waste (ZW) to landfill studies have gained prominence in recent years, but generally there is a lack of clear guidance on how to carry out ZW strategies effectively at either, municipal or institutional levels. To fill this gap, this study aims to provide a framework that enables institutions to develop a goal-oriented WM strategy applying the principles of material flow analysis and life cycle assessment. The framework assumes that no prior data are available, and a study will therefore begin by collecting primary data followed by secondary data. The case study is presented in this article, along with the introduction of the framework, using ZW management scenarios in the Istanbul Technical University Ayazaga Campus. The results of the case study show that, it is not possible to achieve ZW to landfill on university campuses. And simply diverting waste from landfill (min 74% to max ~100%) does not necessarily lead to circularity (min 20% to max ~66%) or directly address public attitudes towards ZW goals.

Patterns of use of malnutrition risk screening in pediatric populations: A survey of current practice among pediatric hospitals in North America.

Information on the use of validated malnutrition risk screening tools in pediatric facilities to guide malnutrition identification, diagnosis, and treatment is scarce. Therefore, a survey of pediatric healthcare facilities and practitioners to ascertain malnutrition risk screening practices in North America was conducted. A pediatric nutrition screening practices survey was developed and sent to members of the American Society for Parenteral and Enteral Nutrition, the Council for Pediatric Nutrition Professionals and the Academy of Nutrition and Dietetics Pediatric Nutrition Practice Group. Respondents represented 113 pediatric hospitals in the United States and six in Canada, of which 94 were inpatient and 59 were outpatient. Nutrition risk screening was completed in 90% inpatient settings, and 63% used a validated screening tool. Nurses performed most malnutrition risk screens in the inpatient setting. Nutrition risk screening was reported in 51% of outpatient settings, with a validated screening tool being used in 53%. Measured anthropometrics were used in 78% of inpatient settings, whereas 45% used verbally reported anthropometrics. Measured anthropometrics were used in 97% outpatient settings. Nutrition risk screening was completed in the electronic health record in 80% inpatient settings and 81% outpatient settings. Electronic health record positive screen generated an automatic referral in 80% of inpatient and 45% of outpatient settings. In this sample of pediatric healthcare organizations, the results demonstrate variation in pediatric malnutrition risk screening in North America. These inconsistencies justify the need to standardize pediatric malnutrition risk screening using validated pediatric tools and allocate resources to perform screening.

Blending phosphogypsum to mitigate radionuclide leaching for sustainable road base applications.

Production of phosphoric acid generates a calcium sulfate byproduct known as phosphogypsum (PG). PG is not considered a suitable standalone road base material because of concerns such as strength and presence of radionuclides. This paper investigates the latter, specifically the influence of blending PG with common alkaline road base aggregates - limerock (LR) and recycled concrete aggregate (RCA) - on radionuclide leaching. Radionuclide leaching from several PG sources was assessed for gross alpha, gross beta, uranium, and combined radium (226 + 228). Solution pH affected Ra226 mobility, with minimum concentrations exhibited at a pH in the range of 6 to 8. Mobile Ra226 concentrations in RCA blends decreased compared to original PG; Ra226 mobility initially increased at low LR replacements but decreased with increasing mass of LR (50 %-75 %). The data suggest an additional mechanism beyond pH alone impacted Ra226 mobility from the blends, possibly the binding or substitution of radium by elevated concentrations of Ba, Sr, or Ca. Blending with RCA resulted in radionuclide concentrations below respective drinking water thresholds, mitigating leaching concern from PG-RCA road base blends. PG-LR blends can meet regulatory limits when incorporating appropriate PG sources, providing an avenue for PG-amended road base materials. The blending approach reduced Ra226 mobility from PG-amended base, accommodating more PG use, serving as an alternative scenario to end-of-life stacking.

Biorenewable Exfoliation of Electronic-Grade Printable Graphene Using Carboxylated Cellulose Nanocrystals.

The absence of scalable and environmentally sustainable methods for producing electronic-grade graphene nanoplatelets remains a barrier to the industrial-scale application of graphene in printed electronics and conductive composites. To address this unmet need, here we report the utilization of carboxylated cellulose nanocrystals (CNCs) extracted from the perennial tall grass Miscanthus × giganteus as a biorenewable dispersant for the aqueous liquid-phase exfoliation of few-layer graphene nanoplatelets. This CNC-based exfoliation procedure was optimized using a Bayesian machine learning model, resulting in a significant graphite-to-graphene conversion yield of 13.4% and a percolating graphene thin-film electrical conductivity of 3.4 × 104 S m-1. The as-exfoliated graphene dispersions were directly formulated into an aerosol jet printing ink using cellulose-based additives to achieve high-resolution printing (∼20 µm line width). Life cycle assessment of this CNC-based exfoliation method showed substantial improvements for fossil fuel consumption, greenhouse gas emissions, and water consumption compared to incumbent liquid-phase exfoliation methods for electronic-grade graphene nanoplatelets. Mechanistically, potential mean force calculations from molecular dynamics simulations reveal that the high exfoliation yield can be traced back to the favorable surface interactions between CNCs and graphene. Ultimately, the use of biorenewable CNCs for liquid-phase exfoliation will accelerate the scalable and eco-friendly manufacturing of graphene for electronically conductive applications.

Life cycle environmental impacts of urban water systems in China.

Urban water systems in China are facing multiple challenges, including rapid urbanisation, climate change and infrastructure ageing. It is crucial to evaluate their environmental performance from a holistic perspective in planning and management processes. To the best of our knowledge, there is a lack of nationwide life cycle assessment (LCA) studies on China's urban water systems that cover all system stages. Therefore, this study aims to present a comprehensive and nationwide LCA analysis that pinpoints the environmental hotspots and their major sources across China. This study was conducted based on water utility databases at the province level, covering water abstraction and treatment, waterwork sludge treatment, water distribution, sewage collection, stormwater drainage, wastewater treatment and sewage sludge treatment. Nine environmental impact categories were calculated and analysed. The results reveal the inequity of environmental impacts across provinces, with overall impacts geographically higher in the east and south, lower in the west and north. However, at the functional unit level, the impacts in the northern and northeastern provinces are higher than other regions. Most environmental categories are dominated by multiple water system stages. The analyses of underlying drivers found that purchased electricity is the primary source of several environmental impacts. This study provides a holistic understanding of the environmental performance of China's urban water systems, offers some insights for comprehensive decision-making support on sustainable water system management, and can also serve as a benchmark for future scenario analysis to explore options for reducing environmental impact.