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Improving urban air quality is a pressing challenge in the Global South. A key source of air pollution is the informal burning of household waste. Reducing informal burning requires governments to develop formal systems for waste disposal and for residents to adopt new disposal behaviors. Using a randomized experiment, we show that social competitions between pairs of neighborhoods in Nansana municipality, Uganda, galvanized leadership and inspired collective action to reduce informal burning. All 44 neighborhoods in the study received a public health campaign, while 22 treated neighborhoods were paired and competed to reduce waste burning over an 8-mo period. Treated neighborhoods showed a 24 percent reduction (95% CI: 11 to 35 percent) in waste burning relative to control neighborhoods at the end of the competition period. There is no evidence that treated neighborhoods experienced a rebound in waste burning several months after the competitions. Community leaders reported greater effort in coordinating residents and more pride in their neighborhood when assigned to the competition treatment. These results suggest that creating focal points for leadership and collective action can be an effective and low-cost strategy to address policy problems that require broad participation and costly behavior change.

The pozzolanic reaction of fly ashes with calcium-based additives can be effectively used to solidify and chemically stabilize (S&S process) highly concentrated brines inside a cementitious matrix. However, complex interactions between the fly ash, the additive, and the brine typically affect the phases formed at equilibrium, and the resulting solid capacity to successfully encapsulate the brine and its contaminants. Here, the performances of two types of fly ash (a Class C and Class F fly ash) are assessed when combined with different additives (two types of cement, or lime with and without NaAlO2), and two types of brine (NaCl or CaCl2) over a range of concentrations (0 ≤ [Cl-] ≤ 2 M). The best performing matrices - i.e., the matrices with the highest Cl-containing phases content - were identified using XRD and TGA. The experimental results were then combined with thermodynamic modeling to dissociate the contribution of the fly ash from that of the additives. All results were implemented in a machine learning model that showed good accuracy at predicting the fly ash degree of reaction, allowing for the robust prediction of extended systems performance when combined with thermodynamic modeling.

Low carbon fuel and waste management policies at the federal and state levels have catalyzed the construction of Californias wet anaerobic digestion (AD) facilities. Wet ADs can digest food waste and dairy manure to produce compressed natural gas (CNG) for natural gas vehicles or electricity for electric vehicles (EVs). Carbon capture and sequestration (CCS) of CO2 generated from AD reduces the fuel carbon intensity by carbon removal in addition to avoided methane emissions. Using a combined lifecycle and techno-economic analysis, we determine the most cost-effective design under current and forthcoming federal and state low carbon fuel policies. Under many scenarios, designs that convert biogas to electricity for EVs (Biogas to EV) are favored; however, CCS is only cost-effective in these systems with policy incentives that exceed $200/tonne of CO2 captured. Adding CCS to CNG-producing systems (Biogas to CNG) only requires a single unit operation to prepare the CO2 for sequestration, with a sequestration cost of $34/tonne. When maximizing negative emissions is the goal, incentives are needed to either (1) fund CCS with Biogas to EV designs or (2) favor CNG over electricity production from wet AD facilities.

There is an urgent requirement to minimize food waste and create more sustainable food systems that address global increases in malnutrition and hunger. The nutritional value of brewers spent grain (BSG) makes it attractive for upcycling into value-added ingredients rich in protein and fiber having a lower environmental impact than comparable plant-based ingredients. BSG is predictably available in large quantities globally and can therefore play a role in addressing hunger in the developing world via the fortification of humanitarian food aid products. Moreover, addition of BSG-derived ingredients can improve the nutritional profile of foods commonly consumed in more developed regions, which may aid in reducing the prevalence of dietary-related disease and mortality. Challenges facing the widespread utilization of upcycled BSG ingredients include regulatory status, variability of raw material composition, and consumer perception as low-value waste products; however, the rapidly growing upcycled food market suggests increasing consumer acceptability and opportunities for significant market growth via effective new product innovation and communication strategies.

Organic waste streams can be converted into high-value platform chemicals such as medium-chain carboxylic acids (MCCAs) using mixed microbial communities via chain elongation. However, the heterogeneity of waste streams and the use of complex microbial communities can lead to undesirable reactions, thus decreasing process efficiency. We explored suppressing excessive ethanol oxidation to acetate (EEO) by increasing the hydrogen partial pressure (PH2) through hydrogenotrophic methanogenesis inhibition by periodically adding 2-bromoethanesulfonate (2-BES) to an MCCA-producing bioreactor to reach 10 mM of 2-BES upon addition. The bioreactor was fed with pretreated food waste and brewery waste containing high concentrations of short-chain carboxylic acids and ethanol, respectively. While 2-BES addition initially reduced EEO, some methanogens (Methanobrevibacter spp.) persisted and resistant populations were selected over time. Besides changing the methanogenic community structure, adding 2-BES also changed the bacterial community structure due to its impact on PH2. While we demonstrated that PH2 could be manipulated using 2-BES to control EEO, methods that do not require the addition of a chemical inhibitor should be explored to maintain optimum PH2 for long-term suppression of EEO.

Scalable, low-cost biofuel and biochemical production can accelerate progress on the path to a more circular carbon economy and reduced dependence on crude oil. Rather than producing a single fuel product, lignocellulosic biorefineries have the potential to serve as hubs for the production of fuels, production of petrochemical replacements, and treatment of high-moisture organic waste. A detailed techno-economic analysis and life-cycle greenhouse gas assessment are developed to explore the cost and emission impacts of integrated corn stover-to-ethanol biorefineries that incorporate both codigestion of organic wastes and different strategies for utilizing biogas, including onsite energy generation, upgrading to bio-compressed natural gas (bioCNG), conversion to poly(3-hydroxybutyrate) (PHB) bioplastic, and conversion to single-cell protein (SCP). We find that codigesting manure or a combination of manure and food waste alongside process wastewater can reduce the biorefinery's total costs per metric ton of CO2 equivalent mitigated by half or more. Upgrading biogas to bioCNG is the most cost-effective climate mitigation strategy, while upgrading biogas to PHB or SCP is competitive with combusting biogas onsite.

Food waste is a dominant organic constituent of landfills, and a large global source of greenhouse gases. Composting food waste presents a potential opportunity for emissions reduction, but data on whole pile, commercial-scale emissions and the associated biogeochemical drivers are lacking. We used a non-invasive micrometeorological mass balance approach optimized for three-dimensional commercial-scale windrow compost piles to measure methane (CH4), nitrous oxide (N2O), and carbon dioxide (CO2) emissions continuously during food waste composting. Greenhouse gas flux measurements were complemented with continuous oxygen (O2) and temperature sensors and intensive sampling for biogeochemical processes. Emission factors (EF) ranged from 6.6 to 8.8 kg CH4-C/Mg wet food waste and were driven primarily by low redox and watering events. Composting resulted in low N2O emissions (0.01 kg N2O-N/Mg wet food waste). The overall EF value (CH4 + N2O) for food waste composting was 926 kgCO2e/Mg of dry food waste. Composting emissions were 38-84% lower than equivalent landfilling fluxes with a potential net minimum savings of 1.4 MMT CO2e for California by year 2025. Our results suggest that food waste composting can help mitigate emissions. Increased turning during the thermophilic phase and less watering overall could potentially further lower emissions.

According to industry estimates, approximately 7 billion day-old male chicks are disposed of annually worldwide because they are not of use to the layer industry. A practical process to identify the sex of the egg early in incubation without penetrating the egg would improve animal welfare, reduce food waste and mitigate environmental impact. We implemented a moderate vacuum pressure system through commercial egg-handling suction cups to collect volatile organic compounds (VOCs). Three separate experiments were set up to determine optimal conditions to collect eggs VOCs to discriminate male from female embryos. Optimal extraction time (2 min), storage conditions (short period of incubation during egg storage (SPIDES) at days 8-10 of incubation), and sampling temperature (37.5°C) were determined. Our VOC-based method could correctly differentiate male from female embryos with more than 80% accuracy. These specifications are compatible with the design of specialized automation equipment capable of high-throughput, in-ovo sexing based on chemical sensor microchips.

This case study investigated waste management in a small, rural, Queensland hospital identifying areas where staff could reduce CO2e within the context of what is logistically possible. Phase I captured waste streams and disposal data for 1 May 2022–31 May 23 in a 20-bed Queensland Health hospital and included three audits of the hospital’s pharmaceutical waste bin. Phase II comprised semi-structured interviews with seven staff. Most potentially recyclable waste was being disposed of in the clinical, pharmaceutical, and general waste streams. All participants were interested in recycling more if appropriate bins were accessible in their work and lunch areas and recycling education was provided. Between 1 May 2022 and 31 May 2023, the CO2e were 44.53t, which equates to approximately 48,327 car km. This study identified opportunities for hospital-wide recycling which would reduce CO2e, waste collection fees, and landfill volume. A limitation was the small number of interviewees due to rural workforce shortages and a COVID-19 outbreak. [ABSTRACT FROM AUTHOR]

Iron (Fe)-based groundwater treatment removes carcinogenic arsenic (As) effectively but generates toxic As-rich Fe oxide water treatment residuals (As WTRs) that must be managed appropriately to prevent environmental contamination. In this study, we apply life cycle assessment (LCA) to compare the toxicity impacts of four common As WTR disposal strategies that have different infrastructure requirements and waste control: (i) landfilling, (ii) brick stabilization, (iii) mixture with organic waste, and (iv) open disposal. The As disposal toxicity impacts (functional unit = 1.0 kg As) are compared and benchmarked against impacts of current methods to produce marketable As compounds via As mining and concentrate processing. Landfilling had the lowest non-carcinogen toxicity (2.0 × 10-3 CTUh), carcinogen toxicity (3.8 × 10-5 CTUh), and ecotoxicity (4.6 × 103 CTUe) impacts of the four disposal strategies, with the largest toxicity source being As emission via sewer discharge of treated landfill leachate. Although landfilling had the lowest toxicity impacts, the stored toxicity of this strategy was substantial (ratio of stored toxicity/emitted As = 13), suggesting that landfill disposal simply converts direct As emissions to an impending As toxicity problem for future generations. The remaining disposal strategies, which are frequently practiced in low-income rural As-affected areas, performed poorly. These strategies yielded ∼3-10 times greater human toxicity and ecotoxicity impacts than landfilling. The significant drawbacks of each disposal strategy indicated by the LCA highlight the urgent need for new methods to recover As from WTRs and convert it into valuable As compounds. Such advanced As recovery technologies, which have not been documented previously, would decrease the stored As toxicity and As emissions from both WTR disposal and from mining As ore.

Air intrusion into municipal solid waste landfills can cause a localized switch from anaerobic to aerobic biodegradation adjacent to the intrusion. The purpose of this study was to explore the effects on temperature and gas composition of air intrusion into an idealized anaerobic landfill. Two scenarios of air intrusion and injection were simulated using a mechanistic landfill model built into TOUGH2. The modeled landfill geometry and properties are based on an actual U.S. landfill. The simulation results show that air intrusion can cause a quick switch from anaerobic to aerobic conditions and as a result, cause a fast increase in temperature of up to 30 °C associated with stimulation of aerobic biodegradation reactions. Associated with the change to aerobic conditions is a decrease in CH4/CO2 (v/v) ratio in the landfill gas. Depending on the air flow rate intruding or injecting into the landfill, localized aerobic biodegradation is stimulated and as a result heat generation rate of 10 to 150 W/m3 leads to temperature increase. Temperature increase near a temporary air intrusion lasts no longer than a few weeks while the high temperatures in deep layers could last up to one year.

Public schools in the U.S. generate about 14,500 tons of municipal solid waste daily, and approximately 42% of that is food packaging generated by school foodservice, contributing significantly to the global packaging waste crisis. This literature review summarizes methods used to evaluate food packaging waste in school foodservice. This review has two objectives: first, to understand which methodologies currently exist to evaluate food packaging waste generation and disposal in school foodservice; and second, to describe the creation of and share a practical standardized instrument to evaluate food packaging waste generation and disposal in school foodservice. A systematic review was conducted using the following search terms: solid waste, school, cafeteria and food packaging, waste, and school. The final review included 24 studies conducted in school environments (kindergarten through twelfth grade or college/university), 16 of which took place in the U.S. Food packaging waste evaluations included objective methods of waste audits, models, and secondary data as well as subjective methods of qualitative observations, questionnaires, interviews, and focus groups. Large variation exists in the settings, participants, designs, and methodologies for evaluating school foodservice packaging waste. Lack of standardization was observed even within each methodology (e.g., waste audit). A new instrument is proposed to support comprehensive and replicable data collection, to further the understanding of school foodservice food packaging waste in the U.S., and to reduce environmental harms.

Diverting organic waste from landfills provides significant emissions benefits in addition to preserving landfill capacity and creating value-added energy and compost products. Dry anaerobic digestion (AD) is particularly attractive for managing the organic fraction of municipal solid waste because of its high-solids composition and minimal water requirements. This study utilizes empirical data from operational facilities in California in order to explore the key drivers of dry AD facility profitability, impacts of market forces, and the efficacy of policy incentives. The study finds that dry AD facilities can achieve meaningful economies of scale with organic waste intake amounts larger than 75,000 tonnes per year. Materials handling costs, including the disposal of inorganic residuals from contaminated waste streams and post-digester mass (digestate) management, are both the largest and the most uncertain facility costs. Facilities that utilize the biogas for vehicle fueling and earn associated fuel credits collect revenues that are 4-6x greater than those of facilities generating and selling electricity and 10-12x greater than facilities selling natural gas at market prices. The results suggest important facility design elements and enabling policies to support an increased scale of organic waste handling infrastructure.

Polyhydroxyalkanoates (PHA) are a family of microbial polyesters that are used as biodegradable plastics in replacement of conventional plastics for various applications. However, the high production cost is the barrier for PHA market expansion. This study aimed to utilize food waste as low-cost feedstock to produce poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) by Haloferax mediterranei. The effects of acetate (Ac), propionate (Pr), butyrate (Bu), and the short-chain carboxylates derived from food waste were examined on the microbial growth and PHBV production. Results showed that a mixture of carboxylates provided a 55% higher PHBV yield than glucose. The food-waste-derived nutrients achieved the yields of 0.41 to 0.54 g PHBV/g Ac from initial loadings of 450 mg/l to 1,800 mg/l Ac of total carboxylates. And the consumption of individual carboxylate varied between different compositions of the carbon source. The present study demonstrates the potential of using food waste as feedstock to produce PHBV by Haloferax mediterranei, which can provide economic benefits to the current PHA industry. Meanwhile, it will also help promote organic waste reduction in landfills and waste management in general.

Waste-to-energy systems can play an important role in diverting organic waste from landfills. However, real-world waste management can differ from idealized practices, and emissions driven by microbial communities and complex chemical processes are poorly understood. This study presents a comprehensive life-cycle assessment, using reported and measured data, of competing management alternatives for organic municipal solid waste including landfilling, composting, dry anaerobic digestion (AD) for the production of renewable natural gas (RNG), and dry AD with electricity generation. Landfilling is the most greenhouse gas (GHG)-intensive option, emitting nearly 400 kg CO2e per tonne of organic waste. Composting raw organics resulted in the lowest GHG emissions, at -41 kg CO2e per tonne of waste, while upgrading biogas to RNG after dry AD resulted in -36 to -2 kg CO2e per tonne. Monetizing the results based on social costs of carbon and other air pollutant emissions highlights the importance of ground-level NH3 emissions from composting nitrogen-rich organic waste or post-AD solids. However, better characterization of material-specific NH3 emissions from landfills and land-application of digestate is essential to fully understand the trade-offs between alternatives.

Debates about whether a healthy diet is affordable often overlook how low-income consumers themselves evaluate food cost. This question is relevant to explaining food choices and measuring food prices. Drawing on interviews with 49 low-income primary caregivers and grocery-shopping observations with 34 of these interviewees, I find that respondents judge food cost in two ways: 1) absolute judgments, or assessments of whether a food covers a family's needs with scarce resources and 2) relative judgments, or interpretations of price relative to another food that frames an item as affordable or pricey by contrast. Absolute judgments reflect actual expenditures, including not just the sticker price, but also four underappreciated monetary costs. These underappreciated costs stem from food waste; packages containing more than is needed; food that is consumed too quickly; and unsatiating foods. When monetary costs go unmeasured and when consumers interpret prices in relative terms, researchers' views of food cost diverge from the experiences of low-income people. Divergent views have two results: food-cost estimates overstate the affordability of a healthy diet and observers may misconstrue purchases as financially imprudent. These findings can inform policy, programming, and public discourse.

Lignocellulose comprises a significant portion of municipal solid waste (MSW) - 40-70% in developed countries, including paper, wood, and yard waste. Cellulose and hemicellulose are often shielded by lignin, posing a barrier to waste decomposition and landfill gas generation. Unfortunately, lignin is resistant to microbial degradation under low-oxygen conditions that normally occur in MSW landfills. The bacterium strain TAV5, microaerophilic and member of phylum Verrucomicrobia, isolated from the hindgut of the Reticulitermes flavipes termite, the most widely distributed subterranean termite in North America. Its genome contains genes associated with methylotrophic competency which code for enzymes that structurally modify lignin. The overall goal of this research was to use TAV5 to modify lignin and boost methane production from MSW. Batch-scale reactors (125 mL) were filled with paper, yard, or wood waste, and four ratios of mixed of waste. Reactors were seeded with different ratios of TAV5 to anaerobic digester (AD) microorganisms (representing landfill anaerobic microorganisms). Based on batch tests, optimal ratios of TAV5 to AD microorganisms were used to seed wastes (mixed, yard, and wood) in 6-gallon reactors. Addition of TAV5 increased methane production from mixed waste, yard waste, and wood, by 49%, 34%, and 297%, respectively. TAV5 decreased acid soluble lignin by 7-39%, depending on waste type. TAV5 grown under aerobic conditions and room temperature (not requiring a heated anaerobic chamber) was found to remain viable and increase methane production under low-level oxygen conditions (1-2%). This finding will potentially lessen costs for growing large volumes of it for seeding landfills.

Biogas is a renewable energy source composed of methane, carbon dioxide, and other trace compounds produced from anaerobic digestion of organic matter. A variety of feedstocks can be combined with different digestion techniques that each yields biogas with different trace compositions. California is expanding biogas production systems to help meet greenhouse gas reduction goals. Here, we report the composition of six California biogas streams from three different feedstocks (dairy manure, food waste, and municipal solid waste). The chemical and biological composition of raw biogas is reported, and the toxicity of combusted biogas is tested under fresh and photochemically aged conditions. Results show that municipal waste biogas contained elevated levels of chemicals associated with volatile chemical products such as aromatic hydrocarbons, siloxanes, and certain halogenated hydrocarbons. Food waste biogas contained elevated levels of sulfur-containing compounds including hydrogen sulfide, mercaptans, and sulfur dioxide. Biogas produced from dairy manure generally had lower concentrations of trace chemicals, but the combustion products had slightly higher toxicity response compared to the other feedstocks. Atmospheric aging performed in a photochemical smog chamber did not strongly change the toxicity (oxidative capacity or mutagenicity) of biogas combustion exhaust.

The U.S. places approximately 53% of its total municipal solid waste (MSW) in landfills, but state and local governments across the country are now setting ambitious environmental and waste diversion policies requiring, among other things, diversion and utilization of organics. Municipalities across the U.S. are employing anaerobic digestion (AD) as part of their strategy to divert organic MSW from landfills, produce biogas, and yield other beneficial coproducts such as compost and fertilizer. However, AD faces many technical, regulatory, and economic barriers to greater deployment, including upstream waste contamination, local odor and air pollution concerns, lengthy siting and permitting processes, and requirements and sizable costs for interconnecting to the electric grid. We identify a combination of scientific, operational, and policy advancements that are needed to address these barriers.

Emissions of twelve (hydro)chlorofluorocarbons (F-gases) and methane were quantified using large-scale static chambers as a function of cover type (daily, intermediate, final) and seasonal variation (wet, dry) at a California landfill. The majority of the F-gas fluxes was positive and varied over 7 orders of magnitude across the cover types in a given season (wet: 10-8 to 10-1 g/m2-day; dry: 10-9 to 10-2 g/m2-day). The highest fluxes were from active filling areas with thin, coarse-grained daily covers, whereas the lowest fluxes were from the thick, fine-grained final cover. Historical F-gas replacement trends, waste age, and cover soil geotechnical properties affected flux with significantly lower F-gas fluxes than methane flux (10-4 to 10+1 g/m2-day). Both flux and variability of flux decreased with the order: daily to intermediate to final covers; coarser to finer cover materials; low to high fines content cover soils; high to low degree of saturation cover soils; and thin to thick covers. Cover-specific F-gas fluxes were approximately one order of magnitude higher in the wet than dry season, due to combined effects of comparatively high saturations, high void ratios, and low temperatures. Emissions were primarily controlled by type and relative areal extent of cover materials and secondarily by season.

Understanding the microbial ecology of landfills is crucial for improving waste management strategies and utilizing the potential of these microbial communities for biotechnological applications. This study aimed to conduct a comprehensive taxonomic and functional profiling of the microbial community present in the Addis Ababa municipal solid waste dumpsite using a shotgun metagenomics sequencing approach. The taxonomic analysis of the sample revealed the significant presence of bacteria, with the Actinomycetota (56%), Pseudomonadota (23%), Bacillota (3%), and Chloroflexota (3%) phyla being particularly abundant. The most abundant KEGG categories were carbohydrates metabolism, membrane transport, signal transduction, and amino acid metabolism. The biodegradation and metabolism of xenobiotics, as well as terpenoids and polyketides, were also prevalent. Moreover, the Comprehensive Antibiotic Resistance Database (CARD) identified 52 antibiotic resistance gene (ARG) subtypes belonging to 14 different drug classes, with the highest abundances observed for glycopeptide, phosphonic acid, and multidrug resistance genes. Actinomycetota was the dominant phylum harboring ARGs, followed by Pseudomonadota and Chloroflexota. This study offers valuable insights into the taxonomic and functional diversity of the microbial community in the Addis Ababa municipal solid waste dumpsite. It sheds light on the widespread presence of metabolically versatile microbes, antibiotic resistance genes, mobile genetic elements, and pathogenic bacteria. This understanding can contribute to the creation of efficient waste management strategies and the investigation of possible biotechnological uses for these microbial communities., Competing Interests: Declarations Competing interests The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

California's organic waste diversion law, SB 1383, mandates a 75% reduction in organics disposal by 2025 to reduce landfill methane emissions. Composting will likely be the primary alternative to landfilling, and 75-100 new large-scale composting facilities must be sited in the state to meet its diversion goal. We developed a strategy for evaluating site suitability for commercial composting by incorporating land-use, economic, and environmental justice criteria. In our Baseline scenario, we identified 899 candidate sites, and nearly all are within a cost-effective hauling distance of cropland and rangelands for compost application. About half of sites, mostly in rural areas, are not within a cost-effective collection distance of enough municipal organics to supply an average-sized facility. Conversely, sites near cities have greater access to organics but cause greater health damages from ammonia and volatile organic compounds emitted during the composting process. The additional required composting capacity corresponds to $266-355 million in annual damages from air pollution. However, this excludes avoided emissions from landfilling, and damages could be reduced by 56% if aerated static piles are used instead of windrows. Siting a higher number of smaller decentralized facilities could also help equally distribute air pollution to avoid concentrating burdens in certain communities.

Leaching of per- and polyfluoroalkyl substances (PFAS) during the post-consumer disposal of food contact materials (FCMs) poses a potential environmental threat but has seldom been evaluated. This study characterized the leaching behavior of PFAS and unidentified precursors from six common FCMs and assessed the impact of environmental conditions on PFAS release during disposal. The total concentration of 21 PFAS ranged from 3.2 to 377 ng/g in FCMs, with PFAS leachability into water varying between 1.1-42.8 %. Increasing temperature promoted PFAS leaching, with leached nine primary PFAS (∑ 9 PFAS) reaching 46.3, 70.4, and 102 ng/L at 35, 45, and 55 ℃, respectively. Thermodynamic analysis (∆G>0, ∆H>0, and ∆S<0) indicated hydrophobic interactions control PFAS leaching. The presence of dissolved organic matter in synthetic leachate increased the leached ∑ 9 PFAS from 47.1 to 103 ng/L but decreased PFBS, PFOS, and 6:2 FTS leaching. The total release of seven perfluorocarboxylic acids (∑ 7 PFCAs) from takeaway food packaging waste was estimated to be 0.3-8.2 kg/y to landfill leachate and 0.6-15.4 kg/y to incineration plant leachate, contributing 0.2-4.8 % and 0.1-3.2 % of total ∑ 7 PFCAs in each leachate type. While the study presents a refined methodology for estimating PFAS release during disposal, future research is needed on the indirect contribution from precursors., 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 B.V. All rights reserved.)

Effective solid waste management is a critical environmental challenge, particularly in rapidly growing Global South countries like Nigeria. This issue is exacerbated by burgeoning populations, lax waste regulations, and the widespread practice of open dumping. The deterioration of soil quality and alteration of water quality are major consequences of open waste dumping, posing significant environmental and public health risks. This study aims to assess the environmental risk and pollution status of soil and water resources near major dumpsites in Lagos. It aims to offer insights that can inform targeted interventions and policy measures not only in Lagos but also in comparable urban settings worldwide. Results indicated that important soil parameters, including TN (11.89-13.83 mg/kg), pH (6.45-7.35), sulfate (36.71-39.49 mg/kg), phosphate (9.31-14.39 mg/kg), and electrical conductivity (342-566 µS/cm), were significantly affected by the dumpsites. Additionally, concentrations of heavy metals varied, with some exceeding permissible limits set by international standards, highlighting the environmental challenges posed by improper waste disposal in urban settings like Lagos. The analyzed parameters for water were mostly within acceptable limits, indicating a lesser impact of the waste dump on water resources. Water samples from boreholes and hand-dug wells near three dumpsites showed that pH, TDS, and heavy metal concentrations were mostly within WHO limits, with borehole water deemed safe for drinking and hand-dug wells suitable for cleaning. To alleviate the environmental impacts of open dumpsites, it is recommended to implement effective waste segregation, recycling programs, controlled landfilling, and investment in waste treatment technologies, along with regular water quality monitoring to prevent further pollution and protect public health. While these measures offer opportunities, they also face significant challenges due to financial and land constraints. Therefore, strong public awareness, infrastructure investment, and government commitment are essential, along with coordinated efforts among the government, private sector, and communities., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Co-disposal of hexabromocyclododecane (HBCD)-containing waste during municipal solid waste incineration (MSWI) was conducted, achieving a destruction efficiency exceeding 99.999%. Simultaneous determination of HBCD, polybrominated diphenyl ethers (PBDEs) and polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) at multiple stages of a MSWI plant was performed. This aimed to clarify their concentration and congener variations along the flue, with the goal of elucidating their formation mechanisms and control. This study confirmed that HBCD was present in daily MSW, and that PBDEs and PBDD/Fs can be unintentionally produced. The average mass emission factors of HBCD, PBDEs, and PBDD/Fs from stack gas were 6.4 ± 5.0, 98.8 ± 4.6, and 2.8 ± 1.7 μg t -1 , respectively. HBCD and PBDEs were much higher in slag, raising concerns about the secondary release of brominated pollutants during the reprocessing or reuse of incinerator slag. The concentrations of PBDEs and PBDD/Fs increased after the air pollution control devices, largely due to the "memory effect", with regenerated PBDD/Fs being mainly high-brominated homologs. The disposal of HBCD increased PBDEs concentration and altered PBDD/F homolog distribution. Possible formation pathways of PBDEs and PBDD/Fs from HBCD were proposed. HBCD could degraded into brominated short-chain hydrocarbons and aromatic fragments, which may promote the formation of PBDEs and PBDD/Fs., 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.)

Landfill mining is the prominent solution for the recovery of resources from legacy waste. The bio-earth recovered from landfill mining is being utilized for a variety of applications like application as fertilizer. The presence of microplastic in the recovered bio-earth disrupts its usefulness. This study investigated the composition and microplastic pollution in bio-earth derived from landfill mining at the Bhandewadi landfill, Nagpur, India. Results provided insights into its characterization and presence of microplastic. The average moisture content of the bio-earth was 25.2 ± 1.1% with total organic carbon of 14.3 ± 0.6%. The bio-earth exhibited a C:N ratio of 16.9 ± 5.0, volatile solid content of 24.6 ± 1.0%, and ash content of 75.4 ± 1.0%. Bulk density was 434.3 ± 37.2 kg/m 3 , pH value 6.91 ± 0.28, and electrical conductivity 4.6 ± 0.7 dS/m. Total nitrogen content was 0.9 ± 0.3%, available phosphorus 2.1 ± 0.3 g/kg, and potassium and sodium contents of 12.7 ± 0.4 g/kg and 3.9 ± 0.3 g/kg, respectively. Heavy metals detected included Fe, Zn, Mn, Cu, Pb, Ni, Cr, and Cd. Microplastics in the bio-earth samples were assessed using attenuated total reflectance-Fourier-transform infrared spectroscopy (ATR-FTIR). The amount of microplastics averaged 100,150 ± 29,286 items per kg (dry basis). Additionally, five specific polymer types were prominent as microplastics. Further research and mitigation strategies are necessary to ensure the safe and sustainable use of bio-earth in agriculture and horticulture., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The present study assessed the impact of municipal solid waste dump on the degradation of soil around Orji dump site. A total of 15 soil samples were collected for this study. Twelve soil samples were collected around the dump site at 0 m, 10 m, and 20 m distance and three from Imo State University (IMSU) research farm as control. The samples were collected from the east, west, north, and south of the dump site. The samples were subjected to laboratory analyses. The mean results obtained indicate that the values of the dump site soil parameters analyzed ranged from 86.67 to 89.00% (sand), 4.33 to 5.67% (silt), 7.00 to 7.67% (clay), 6.80 to 7.50 (pH), 4.33 to 7.00 dS m -1 electric conductivity (EC), 0.0028 to 0.0045 mg kg -1 (salinity), 2.36 to 3.76% soil organic matter (SOM), 24.13 to 38.93 cmolc kg -1 cation exchange capacity (CEC), 4.50 to 9.57 cmolc kg -1 calcium (Ca), and 1.0 to 2.25 cmolc kg -1 magnesium (Mg). At the control, mean values were 81.24% (sand), 6.39% (silt), 12.45% (clay), 5.69 (pH), 0.47 dS m -1 (EC), 0.0005 mg kg -1 (salinity), 1.99% (SOM), 5.08 cmolc kg -1 (CEC), 2.17 cmolc kg -1 (Ca), and 1.67 cmolc kg -1 (Mg). These values showed substantial enrichment. Correlations indicate that EC, salinity, and CEC majorly determined the availability of most of the parameters analyzed. Soil degradation index (SDI) was used to determine degradation around the dump site. It ranged from 2.546.61% (0 m) to 1573.50% (10 m) and 1.603.73% (20 m). Thus, distance affected the rate of soil degradation in all directions away from the dump site., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Economic incentive is thought a good intervention type that can encourage residents to do food waste sorting by many cities' government in China. However, there is a lack of long-term, large-scale study. So the business-led incentive scheme was studied by a case study in Nanjing, China, which focuses on food waste sorting. The results showed that the incentive can encourage at most an average 37% of residents to start and then continue to do food waste sorting regularly. Later, the incentive cannot encourage more even with many non-economic interventions. And most of these participating residents (31%) were encouraged at the first 12 months. The results also showed that house price had a negative relationship with the community sorting performance. The comparative study results showed that the community committee must be involved in the non-economic interventions to encourage more residents to take part; otherwise, the company will fail even after many attempts. So the government should apply the incentive policy by dialectical view in food waste sorting. And the incentive scheme should involve all the stakeholders to apply non-economic interventions to encourage more residents to do food waste sorting., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Dry anaerobic digestion (dry-AD) is an attractive process for solid wastes such as agri-food waste. However, some limitations mainly associated to lack of effective mixing, can hinder the methane production capacity of the systems. Bulking agent (BA) has been proposed as a solution to the compaction issues in systems without mechanical agitation, such as leaching bed reactors. However, effects of BA are still not clear, and, thus, the factors to consider for its dose has not been optimized yet. This work studies the effect of BA in dry-AD. Two substrates with different characteristics were proposed as models, bean peel as a lignocellulosic substrate and a mixture of food waste as a readily biodegradable substrate. Inert plastic rings were used as BA at different BA:S ratios. Assessed BA:S ratio did not affect the performance of methane production for the lignocellulosic waste, but it did significantly affect to the easily biodegradable substrate, showing up to a 28% of methane production increase. This result could be due to the presence of lignocellulosic compounds in the bean peel, behaving like a natural BA. In assays with an increased bed height, the compaction of the system was more severe, resulting in the rapid acidification of the processes. At these conditions, the positive effect of BA addition was more marked, allowing methane production and no acidification of the system. Thus, the addition of BA is a suitable strategy for improving methane production or stability in dry-AD systems without requiring the stirring of the systems., 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 The Authors. Published by Elsevier B.V. All rights reserved.)

Fly ash from waste incineration is growing rapidly and has become a global problem. Landfill is the main treatment method, but the release behavior of ultra-alkaline fly ash needs further study. In this study, the release pattern of heavy metals from fly ash, the long-term risk after seepage, and the main control mechanisms were explored by indoor simulation experiments and process simulation modeling. The results show that carbonation is the main control mechanism for the release rate of heavy metals from super-alkaline fly ash, and the release rate is slow at the initial stage, but the release concentration of Zn and Pb may increase tens of times with the continuous reaction between the acidic substances in the leachate and the alkaline substances in the fly ash. The heavy metals released into the leachate can cause the concentration of Zn, Cd and Pb in the groundwater to exceed the standard by 39.50, 6.70 and 5.99 times due to seepage. Furnace type is the key controlling factor for background concentrations of heavy metals in ultra-alkaline fly ash, and the exposure concentrations of Cu, Cd, Zn, and Pb in ultra-alkaline fly ash from grate furnaces as well as the GT1 facility are 4.19, 4.19, 4.14, and 37.5 times greater than those of fluidized beds, respectively, with a higher risk of long-term landfill. Regionally, the regional occupancy rate of heavy metal concentrations indicated that the risk of adequate rainfall was high in the southeastern coastal region, which was five times higher than that in the inland northwest. Therefore, the long-term dynamics and risk evolution of Zn, Cd, and Pb in the groundwater around MSWLs in the coastal area should be paid attention to after the landfilling of ultra-alkaline fly ash in order to ensure the safety of the shallow groundwater environment after landfilling., 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. Published by Elsevier Ltd.)

In the context of the shift toward a closed-loop economy, soil-like fractions from landfills are increasingly seen as a potential raw material. Pollution, including potentially toxic elements (PTEs), limits the use of soil-like fractions. The study objective was to assess the level of contamination with PTEs and the ecological risk of the soil-like fraction from a landfill using an interval method on the basis of a quantile analysis. Quantile analysis allows visualization and interpretation of data based on statistical principles using a cumulative distribution function for the data. Quantiles divide the entire dataset into equal parts by probability, and they indicate the proportion of observations that have a value less than or equal to a given quantile. A study was conducted at a landfill in Volgograd. The contents of Cd, Ni, Pb, Hg, Cu, and Zn were studied in a soil-like fraction. The contents of Hg, Pb, and Zn were low and did not pose any risks to the environment. Cd, Ni, and Cu were the main reasons for the contamination of the soil-like fraction. Quantile analysis has shown that the soil-like fraction is polluted unevenly and is described by several contamination levels. The pollution level with PTEs in the soil-like fraction is low, with a probability of 27-31%. The other part of the soil-like fraction has a pollution level ranging from moderate to very high. The environmental risk of a soil-like fraction is associated with Cd and Ni. With a probability of 23.5%, a soil-like fraction is a high environmental risk and requires a responsible attitude and measures to ensure environmental safety. With probabilities of 29.4% and 47.1%, the complex potential environmental risks of a soil-like fraction are low and moderate, respectively. The soil-like fraction located at a depth of more than 2.5 m has a low level of pollution and a low environmental risk. Potentially, this part of a soil-like fraction can be isolated and, after detoxification, used. The significance of this research lies in providing a novel approach to evaluate the ecological risk of soil-like fractions from landfills, which can inform more effective sustainable waste utilization practices in landfill mining., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Red mud is a promising candidate for promoting the incineration of Refuse Derived Fuel (RDF) and stabilizing the resulting incineration ash. The combustion conditions, notably temperature, significantly steers the migration and transformation of harmful metal components during combustion, and ultimately affect their retention and speciation in the ash residue. The study attempted to investigate the effect of co-combustion temperature on the enrichment and stability of Cr, Ni, Cu, Zn, Cd and Pb within bottom ashes, and to reveal the underlined promotion mechanism of red mud addition. As temperature increased, red mud's active components formed a robust matrix, helping the formation, melting, and vitrification of silicates and aluminosilicates in the bottom ashes. The process significantly contributed to the encapsulation and stabilization of heavy metals such as Ni, Cu, Zn, Cd, and Pb, with their residual fractions ascending to 71.37%, 55.75%, 74.78%, 84.24%, and 93.54%, respectively. Conversely, high temperatures led to an increase in the proportion of Cr in the extremely unstable acid-soluble fraction of the bottom ashes, reaching 31.52%, posing a heightened risk of environmental migration. Considering the stability of heavy metals in the bottom ashes and the combustion characteristics, 800 °C is identified as the optimal temperature for the co-combustion of RDF and red mud, balancing efficiency and environmental safety. The findings will provide valuable insights for the co-utilization strategy of RDF and red mud, contributing to more informed decision-making in waste-to-energy processes., 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.)

Food waste makes up approximately 15% of municipal solid waste generated in the United States, and 95% of food waste is ultimately landfilled. Its bioavailable carbon and nutrient content makes it a major contributor to landfill methane emissions, but also presents an important opportunity for energy recovery. This paper presents the first detailed analysis of monthly food waste generation in California at a county level, and its potential contribution to the state's energy production. Scenarios that rely on excess capacity at existing anaerobic digester (AD) and solid biomass combustion facilities, and alternatives that allow for new facility construction, are developed and modeled. Potential monthly electricity generation from the conversion of gross food waste using a combination of AD and combustion varies from 420 to 700 MW, averaging 530 MW. At least 66% of gross high moisture solids and 23% of gross low moisture solids can be treated using existing county infrastructure, and this fraction increases to 99% of high moisture solids and 55% of low moisture solids if waste can be shipped anywhere within the state. Biogas flaring practices at AD facilities can reduce potential energy production by 10 to 40%.

Introduction  Hazardous healthcare waste produced at home contributes to approximately 0.5% of biomedical waste, and although potentially infectious, is often discarded with other domestic wastes. The study aimed to quantify and compare types and patterns of biomedical waste generated in homes and to assess the knowledge, attitude, and practices regarding biomedical waste among selected urban and rural households in the coastal area of Mangalore city in Karnataka. Methods  A cross-sectional study was conducted in households consisting of rural and urban field practice areas of a tertiary care hospital in coastal Karnataka from November 2017 to February 2018. A pretested semi-structured questionnaire on knowledge, attitude, and practice regarding healthcare waste generated at home was assessed. Qualitative variables of the waste segregation practice, types of biomedical waste, the knowledge, perception, and attitude to practices regarding biomedical waste were expressed in percentages proportions and analyzed using SPSS v.20. Results  Baby diapers were the most common hazardous waste. The number of baby diapers produced daily in rural and urban areas was 32 (42.7%) and 64 (85.3%), respectively. The urban households had better knowledge of possible hazardous healthcare waste at home, 28 (37.33%) compared with 7 (9.3%) in rural households. Seventy-one (94.7%) urban and 49 (65.3%) rural households had a favorable attitude toward the disposal of hazardous domestic biomedical waste. Conclusion  The knowledge, attitudes, and practices regarding hazardous healthcare waste produced at the household level were better among urban households compared with rural households. [ABSTRACT FROM AUTHOR]

High concentrations of DDT and metabolites (ΣDDT) have been detected in sediment and the demersal flatfish hornyhead turbot (Pleuronichtys verticalis) collected from Palos Verdes (PV), California, USA, a site contaminated with over 100 metric tons of DDT throughout 1960s-70s. This study was conducted to assess the transfer of ΣDDT from PV-sediment into polychaetes (Neanthes arenaceodentata) and hornyhead turbot, and to investigate if the responses in turbots from two different laboratory exposures mimic those in turbots caught in PV (PV-turbot). Turbot fed PV-sediment-contaminated polychaete for 7 days had liver concentrations of ΣDDT similar to PV-turbot. After 28 days, ΣDDT also accumulated in livers of turbot gavaged with a ΣDDT mixture. In vitro cell bioassays indicated significant increases of 17β-estradiol equivalents (EEQ) in turbot bile extracts as compared to the control in the 7-day study. These responses corresponded to those measured in PV-fish. Glucocorticoid receptor (GR), anti-androgen receptor (anti-AR), estrogen receptor (ER) or aryl hydrocarbon receptor (AhR) activities were also observed in extracts of PV-sediment, and PV-sediment-exposed worm. Anti-AR, AhR and GR activities were significantly higher in PV-sediment than reference sediment (San Diego, SD). Higher transcripts of hepatic VTG, ERα and ERβ were found in PV-turbot than SD-turbot, but were unaltered in fish exposed to sediment-contaminated worms for the 7-day study. In contrast, liver extracts from the 28-day treatment of ΣDDT showed lower EEQ but similar hepatic VTG and ERβ transcripts relative to those of PV-turbot. These data indicated that trophic transfer of sediment-associated DDT in 7-day exposures corresponded to field measurements of DDT residues and in vitro ER bioactivities, but failed to mimic in vivo biological effects observed in field fish. In contrast, treatment with ΣDDT alone for 28 days mimicked in vivo biological effects of DDTs in PV fish, but did not correspond to liver concentrations or in vitro bioactivities.

Rapid innovation in printed circuit board, and the uncertainties surrounding quantification of the human and environmental health impacts of e-waste disposal have made it difficult to confirm the influence of evolving e-waste management strategies and regulatory policies on materials. To assess these influences, we analyzed hazardous chemicals in a market-representative set of Waste printed circuit boards (WPCBs, 1996-2010). We used standard leaching tests to characterize hazard potential and USEtox® to project impacts on human health and ecosystem. The results demonstrate that command-and-control regulations have had minimal impacts on WPCBs composition and toxicity risks; whereas technological innovation may have been influenced more by resource conservation, including a declining trend in the use of precious metals such as gold. WPCBs remain classified as hazardous under U.S. and California laws because of excessive toxic metals. Lead poses the most significant risk for cancers; zinc for non-cancer diseases; copper had the largest potential impact on ecosystem quality. Among organics, acenaphthylene, the largest risk for cancers; naphthalene for non-cancer diseases; pyrene has the highest potential for ecotoxicological impacts. These findings support the need for stronger enforcement of international policies and technology innovation to implement the strategy of design-for-the-environment and to encourage recovery, recycling, and reuse of WPCBs.

Scholars in the field of theology and biblical studies have extensively explored eco-theology from Genesis creation narratives especially 1:26 and 28. In spite of the good numbers of literature in this field of study, less is known in the area of contextual eco-theology that focuses on Christians and environmental care in Uvwie, Nigeria. Therefore, using the eco-theology approach in the interpretation of Genesis 2:15, this paper examines the importance of Christians’ involvement in environmental care by using Uvwie Local Government Area of Nigeria as a focus point. Drawing on the understandings of דַ בָע) abad) and רַ מָ ש) shamar) in Genesis 2:15 which are translated to mean ‘to serve’, to ‘tend’, ‘to dress’ or to ‘care’, it argues that דַ בָע) abad) and רַ מָ ש) shamar) are veritable Biblical and theological bases for Christian involvement in environmental care in contemporary society such as Uvwie. It shows that Genesis 2:15 implies environmental stewardship and environmental conservation and as such a theological basis for Christians in Uvwie-land to develop a positive attitude towards the community and its environment and desist from dumping refuse indiscriminately in the community. As such this paper contributes to the discourse on climate issues in Africa. Besides, humanities scholars will appreciate the essentiality of Christians’ contribution to a sustainable clean and green environment by becoming custodians of God’s creation. [ABSTRACT FROM AUTHOR]

Scholars in the field of theology and biblical studies have extensively explored eco-theology from Genesis creation narratives especially 1:26 and 28. In spite of the good numbers of literature in this field of study, less is known in the area of contextual eco-theology that focuses on Christians and environmental care in Uvwie, Nigeria. Therefore, using the eco-theology approach in the interpretation of Genesis 2:15, this paper examines the importance of Christians’ involvement in environmental care by using Uvwie Local Government Area of Nigeria as a focus point. Drawing on the understandings of דַ בָע) abad) and רַ מָ ש) shamar) in Genesis 2:15 which are translated to mean ‘to serve’, to ‘tend’, ‘to dress’ or to ‘care’, it argues that דַ בָע) abad) and רַ מָ ש) shamar) are veritable Biblical and theological bases for Christian involvement in environmental care in contemporary society such as Uvwie. It shows that Genesis 2:15 implies environmental stewardship and environmental conservation and as such a theological basis for Christians in Uvwie-land to develop a positive attitude towards the community and its environment and desist from dumping refuse indiscriminately in the community. As such this paper contributes to the discourse on climate issues in Africa. Besides, humanities scholars will appreciate the essentiality of Christians’ contribution to a sustainable clean and green environment by becoming custodians of God’s creation.

Waste pickers constitute a marginalized demographic engaged in the collection of refuse, facing considerable occupational hazards that heighten their susceptibility to contract infectious diseases. Moreover, waste pickers contend with societal stigmatization and encounter barriers to accessing healthcare services. To explore the viral profile of waste pickers potentially linked to their occupational environment, we conducted a metagenomic analysis on 120 plasma specimens sampled from individuals employed at the Cidade Estrutural dumpsite in Brasilia city, Brazil. In total, 60 blood donors served as a comparative control group. Specimens were pooled and subjected to Illumina NextSeq 2000 sequencing. Viral abundance among waste pickers revealed the presence of significant pathogens, including HIV, HCV, and Chikungunya, which were not detected in the control group. Additionally, elevated levels of anelloviruses and Human pegivirus-1 were noted, with a comparable incidence in the control group. These findings underscore the utility of metagenomics in identifying clinically relevant viral agents within underserved populations. The implications of this study extend to informing public health policies aimed at surveilling infectious diseases among individuals facing socioeconomic disparities and limited access to healthcare resources.

Waste management in Lira City, Uganda faces significant challenges, particularly in the area of waste collection. Pollution and health risks from uncollected waste are rampant, posing serious threats to human health and the environment. This persistent problem demands urgent attention and effective solutions to improve waste collection and safeguard the well-being of the community and the natural surroundings. This study aimed to assess households' willingness to pay for improved waste collection services, examine their waste management practices, and identify influencing factors. We employed a multistage sampling technique to randomly select 585 household heads and conducted key informant interviews with city officials and private waste collectors. Data analysis was conducted with STATA 17 and results showed that 48.12% of households were willing to pay an average of UGX 3012 ($0.84) per month for better services. Factors including education level, occupation, distance to waste collection sites, and environmental awareness significantly influenced this willingness. The study highlights a significant gap in public awareness and understanding of efficient solid waste management practices and concludes that enhancing public awareness is crucial for improving environmental health and safety in Lira City., (© 2024. The Author(s).)

The ecology of the Qinghai‒Tibet Plateau is fragile, and the ecosystems in the region are difficult to remediate once damaged. Currently, landfilling is the mainstay of domestic waste disposal in China, and numerous, widely distributed county landfills exist. trace elements (TEs) in waste are gradually released with waste degradation and cannot be degraded in nature, affecting environmental quality and human health. To reduce the chance bias that exists in studies of individual landfills, we selected 11 representative county landfills in Tibet, total of 76 soil samples were collected, eight TEs (arsenic (As), mercury (Hg), chromium (Cr), copper (Cu), lead (Pb), cadmium (Cd), nickel (Ni), and zinc (Zn)) were determined, and analysed for the current status of pollution, risk to human health, and sources of TEs to explore the impact of the landfills. The results showed that only a few landfills had individual TEs exceeding the risk screening value of the Soil Environmental Quality Risk Control Standard for Soil Contamination (GB 15618-2018) (pH > 7.5). Most of the soils around the landfills had moderate levels of pollution, but some individual landfills had higher levels, mainly due to Cd and Hg concentrations. Source analysis showed that Hg originated mainly from atmospheric transport; the other TEs came mainly from the weathering of soil parent material and bedrock. The potential risk from TEs to human health was low, and the risk to children was greater than the risk to adults. Among the three exposure routes, oral ingestion resulted in the highest carcinogenic risk and noncarcinogenic risk, with a contribution rate of more than 95%. Among the TEs, Ni had the highest carcinogenic risk, followed by Cr and As, and As had the highest noncarcinogenic risk., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

This study extended the theory of planned behaviour (TPB) and applied it to analyse influencing factors of food waste separation intention (FSI) among households in central Vietnam. Partial least squares structural equation modelling (PLS-SEM) was employed to analyse the data. The heterogeneity of factors contributing to FSI in cities of three levels was examined using multi-group analysis (MGA). The results indicate that attitudes, subjective norms (SN), perceived behavioural control (PBC), awareness of benefit (AB), information publicity (IP), facility availability (FA), and trust significantly affected FSI of households. MGA results indicated the heterogeneity of impacts of PBC and attitude on FSI of households among three municipal levels. The results will serve as basic data for waste officers, solid-waste management project leaders, non-governmental organisations (NGOs), and other related stakeholders to lay the foundation of food waste management planning in terms of regional scale and local scale. This study will also aid the creation of a circular economy by providing a scientific base for enhancing food waste separation at source in central Vietnam., (© 2024. The Author(s).)

Plastic products are now essential commodities, yet their widespread disposal leads to environmental and human health effects, particularly in developing nations. Therefore, developing nations require comprehensive studies to assess the current state of plastic and plastic waste production to enhance plastic waste management practices. This review analyzes the import and export of plastic and the production of plastic waste in Rwanda, aiming to improve waste management practices. This review used open-access papers, reports, and websites dealing with plastic waste management. In this review, 58 articles from the Web of Science and 86 from other search engines were consulted to write this review. The findings revealed that the daily estimated plastic waste produced per person ranges between 0.012 and 0.056 kg. The estimated amount of plastic waste generated per person per year in Rwanda could be between 4.38 and 20.44 kg. Plastic waste accounts for between 1 and 8% of the total municipal solid waste produced per person per day in the country, which ranges from 219 to 255.5 kg. The average annual amount of imported plastics could reach 568.2881 tons, whereas the average quantity of exported plastics could reach 103.7414 tons. This shows that plastic management practices have not yet adopted technically advanced or improved practices, which should concern efforts to protect our environment. This study suggests approaches that can vastly improve plastic waste management and potentially open massive opportunities for the people of Rwanda., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Concerns about the increasing consumption of medicines have been raised due to their contribution to waste pollution and environmental impacts. However, limited research addresses the profile and disposal practices of household medicines, particularly in Latin America. Therefore, this study analyzes the consumption, waste, and disposal of medicines within households in the commune of La Serena, Chile. Primary data were gathered through a semi-structured survey administered directly to a random sample of 430 households. The results indicate that women play a central role in managing medicines within households, with four therapeutic groups being most frequently used in medicines and generating waste: anti-inflammatory/analgesics, antihypertensives, lowering cholesterol, and antidiabetics. Ninety-six% of respondents were unaware of the collection points for this waste, and they disposed of it mainly in household garbage (78%) and sewage (13%). However, over 70% of them considered storing or disposing of medicines in household garbage or sewage to be "dangerous or very dangerous." Furthermore, 97% expressed support for collection campaigns. These results indicate the need for public policies to establish collection points for this waste and to inform consumers about the responsible use and proper disposal of medicines, particularly for women and patients with chronic illnesses., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Municipal solid waste (MSW) landfills are a significant source of methane (CH 4 ) emissions in the United States, contributing to global warming. Current landfill gas (LFG) management methods, like the landfill cover system and LFG collection system, do not entirely prevent LFG release. Biocovers have the potential to reduce CH 4 emissions through microbial oxidation. However, LFG also contains carbon dioxide (CO 2 ) and trace hydrogen sulfide (H 2 S) depending on waste composition, temperature, moisture content, and age of waste. An innovative biogeochemical cover (BGCC) was developed to tackle these concerns. This cover comprises a biochar-based biocover layer overlaid with a basic oxygen furnace (BOF) steel slag layer. The biochar-based biocover layer oxidizes CH 4 emissions, while the BOF slag layer reduces CO 2 and H 2 S through carbonation and sulfidation reaction mechanisms. The BGCC system's field performance remains unexamined. Therefore, a large-scale tank setup simulating near-field conditions was developed to evaluate the BGCC system's ability to mitigate CH 4 , CO 2 , and H 2 S from LFG simultaneously. Synthetic LFG was passed through the BGCC in five distinct phases, each designed to simulate the varying gas compositions and flux rates typical of MSW landfill. Gas profiles along the depth were monitored during each phase, and gas removal efficiency was measured. After testing, biocover and BOF slag samples were extracted to analyze physico-chemical properties. Batch tests were also conducted on samples extracted from the biocover and BOF slag layers to determine potential CH 4 oxidation rates and residual CO 2 sequestration capacity. The results showed that the BGCC system's CH 4 removal efficiency decreased with higher CH 4 flux rates, achieving its highest removal (74.7-79.7%) at moderate influx rates (23.9-25.5 g CH 4 /m 2 -day) and reducing to its lowest removal (27.4%) at the highest influx rate (57.5 g CH 4 /m 2 -day). Complete H 2 S removal occurred during Phase 3 in the biocover layer of BGCC system. CH 4 oxidation rates were highest near the upper (277.9 µg CH 4 /g-day) and lowest in the deeper region of the biocover layer. In the tank experiment, CO 2 breakthrough occurred after 156 days due to drying of the BOF slag layer, with an average residual carbonation capacity of 46 gCO 2 /kg slag after moisture adjustment. Overall, the BGCC system effectively mitigated LFG emissions, including CH 4 , CO 2 , and H 2 S, at moderate flux rates, showing promise as a comprehensive solution for LFG management., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The construction and operation of the construction and demolition waste (C&DW) landfills often encounter significant opposition from nearby residents, which is called the "not in my backyard" (NIMBY) effect. However, little is known about the formation mechanism of the NIMBY effect in C&DW landfilling, so this research was conducted for this purpose. First, the influencing factors leading to the NIMBY effect were determined based on a literature review and questionnaire survey. Then, the interrelationship and influencing path of critical factors were revealed using expert interviews and Interpretative Structural Modelling. The results shown that 12 factors from four levels (including residents, society, government, and enterprises) caused the NIMBY effect in C&DW landfilling. These factors formed a complex network comprising 18 influencing paths. Notably, policy and responding measures as pivotal bottom-level factors that trigger the NIMBY effect by indirectly impacting residents' rights awareness and shaping public perception towards C&DW landfill operation enterprises through directly affecting personal interest, cognitive bias, distrust, disposal technology, management level, opinion leader, and other intermediate factors, ultimately triggering the NIMBY effect. Moreover, strategies for mitigating or resolving the NIMBY effect were proposed, such as protecting personal reasonable interests, understanding the potential risks of C&DW landfills rationally, reporting the C&DW landfills from an objective perspective, improving policies and promoting public participation, and enhancing supervision of the C&DW landfills. The study added new knowledge to the current public's NIMBY effect in C&DW landfilling. Meanwhile, it also provided a reference for formulating C&DW landfilling policies and selecting landfill sites., 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.)

Landfills, especially those poorly managed, can negatively affect the environment and human beings through chemical contamination of soils and waters. This study investigates the soils of a historical municipal solid waste (MSW) landfill situated in the heart of a residential zone in the capital of Slovakia, Bratislava, with an emphasis on metal (loid) contamination and its consequences. Regardless of the depth, many of the soils exhibited high metal (loid) concentrations, mainly Cd, Cu, Pb, Sb, Sn and Zn (up to 24, 2620, 2420, 134, 811 and 6220 mg/kg, respectively), classifying them as extremely contaminated based on the geo-accumulation index (I geo >5). The stable lead isotopic ratios of the landfill topsoil varied widely (1.1679-1.2074 for 206 Pb/ 207 Pb and 2.0573-2.1111 for 208 Pb/ 206 Pb) and indicated that Pb contained a natural component and an anthropogenic component, likely municipal solid waste incineration (MSWI) ash and construction waste. Oral bioaccessibility of metal (loid)s in the topsoil was variable with Cd (73.2-106%) and Fe (0.98-2.10%) being the most and least bioaccessible, respectively. The variation of metal (loid) bioaccessibility among the soils could be explained by differences in their geochemical fractionation as shown by positive correlations of bioaccessibility values with the first two fractions of BCR (Community Bureau of Reference) sequential extraction for As, Cd, Mn, Ni, Pb, Sn and Zn. The results of geochemical fractionation coupled with the mineralogical characterisation of topsoil showed that the reservoir of bioaccessible metal (loid)s was calcite and Fe (hydr)oxides. Based on aqua regia metal (loid) concentrations, a non-carcinogenic risk was demonstrated for children (HI = 1.59) but no risk taking into account their bioaccessible concentrations (HI = 0.65). This study emphasises the need for detailed research of the geochemistry of wastes deposited in urban soils to assess the potentially hazardous sources and determine the actual bioaccessibility and human health risks of the accumulated metal (loid)s., 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 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Intelligent packaging embedded with food freshness indicators can monitor food quality and be deployed for food safety and cutting food waste. The innovative nano-inks for dynamic shelf-life printing based on natural food colorant with application in real-time monitoring of shrimp freshness were prepared. Co-assembly of saffron petal anthocyanin (SPA) with hydrophobic curcumin (Cur) into chitin nano-scaffold (particle sizes around 26 ± 8 nm) could deliver hindering SPA leaching, confirmed by FT-IR, FE-SEM, AFM, and color stability test. The best response to pH-sensitivity was found in a ratio of (1:4) Cur/SPA (30% (v/w) in ChNFs that was correlated with the chemical and microbial changes of shrimp during shrimp freshness. However, smart screen-printed inks signified higher responsiveness to pH changes than FFI films. Therefore, smart-printed indicators introduced the excellent potential for a short response time, easy, cost-effective, eco-friendly, co-assembly, great color stabilities, and lifetime for nondestructively freshness monitoring foods and supplements., 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.)

The soil, comprising minerals, organic matter, and living organisms, serves as a critical component of our environment. However, anthropogenic activities, such as uncontrolled sewage disposal and industrial waste, have led to pervasive soil pollution, impacting ecosystems and human health. This comprehensive study scrutinizes the intricate dynamics of soil pollution resulting from open waste dumping, specifically examining its impact on the health of local communities and the environment in Haridwar municipality. In this study, four solid waste dumping sites were meticulously surveyed, with soil samples analyzed for 19 parameters through statistical tools like one-way ANOVA, Kruskal-Wallis tests, soil pollution indices, and potential health risk assessment. The Geo-accumulation Index (Igeo) and contamination factor (CF) followed the heavy metals in the order of Zn > Mn > Fe > Cu in all selected sites. Additionally, a potential health risk assessment considered ingestion, inhalation, and dermal exposure pathways, revealing a high non-carcinogenic risk of metals (Mn > Fe > Zn > Cu) for both children and adults. In the ingestion pathway, the hazard quotient indicated a high risk of metals for both children and adults in the range of 1192.73 to 2066.94 for child and 191.98 to 312.16 for adults. Crucially, the HQ revealed potential health risks, emphasizing the urgency of addressing metal contamination. However, the findings indicate that dumping sites directly or indirectly affects the local people of Haridwar municipality. Therefore, this study provides a baseline framework for minimizing the impact of dumping sites on local population and the environment., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)