ACS Environmental Au最新文献

{"title":"Fire and Oil Led to Complex Mixtures of PAHs on Burnt and Unburnt Plastic during the M/V X-Press Pearl Disaster","authors":"Bryan D. James*,&nbsp;Christopher M. Reddy,&nbsp;Mark E. Hahn,&nbsp;Robert K. Nelson,&nbsp;Asha de Vos*,&nbsp;Lihini I. Aluwihare,&nbsp;Terry L. Wade,&nbsp;Anthony H. Knap and Gopal Bera,&nbsp;","doi":"10.1021/acsenvironau.3c00011","DOIUrl":"https://doi.org/10.1021/acsenvironau.3c00011","url":null,"abstract":"<p >In May 2021, the M/V <i>X-Press Pearl</i> container ship burned for 2 weeks, leading to the largest maritime spill of resin pellets (nurdles). The disaster was exacerbated by the leakage of other cargo and the ship’s underway fuel. This disaster affords the unique opportunity to study a time-stamped, geolocated release of plastic under real-world conditions. Field samples collected from beaches in Sri Lanka nearest to the ship comprised nurdles exposed to heat and combustion, burnt plastic pieces (pyroplastic), and oil-plastic agglomerates (petroplastic). An unresolved question is whether the 1600+ tons of spilled and recovered plastic should be considered hazardous waste. Due to the known formation and toxicity of combustion-derived polycyclic aromatic hydrocarbons (PAHs), we measured 20 parent and 21 alkylated PAHs associated with several types of spilled plastic. The maximum PAH content of the sampled pyroplastic had the greatest amount of PAHs recorded for marine plastic debris (199,000 ng/g). In contrast, the sampled unburnt white nurdles had two orders of magnitude less PAH content. The PAH composition varied between the types of spilled plastic and presented features typical of and conflicting with petrogenic and pyrogenic sources. Nevertheless, specific markers and compositional changes for burning plastics were identified, revealing that the fire was the main source of PAHs. Eight months after the spill, the PAH contents of sampled stray nurdles and pyroplastic were reduced by more than 50%. Due to their PAH content exceeding levels allowable for plastic consumer goods, classifying burnt plastic as hazardous waste may be warranted. Following a largely successful cleanup, we recommend that the Sri Lankans re-evaluate the identification, handling, and disposal of the plastic debris collected from beaches and the potential exposure of responders and the public to PAHs from handling it. The maritime disaster underscores pyroplastic as a type of plastic pollution that has yet to be fully explored, despite the pervasiveness of intentional and unintentional burning of plastic globally.</p>","PeriodicalId":29801,"journal":{"name":"ACS Environmental Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsenvironau.3c00011","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49768646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a Soft Sensor Using Machine Learning Algorithms for Predicting the Water Quality of an Onsite Wastewater Treatment System","authors":"Hsiang-Yang Shyu,&nbsp;Cynthia J. Castro,&nbsp;Robert A. Bair,&nbsp;Qing Lu and Daniel H. Yeh*,&nbsp;","doi":"10.1021/acsenvironau.2c00072","DOIUrl":"10.1021/acsenvironau.2c00072","url":null,"abstract":"<p >Developing advanced onsite wastewater treatment systems (OWTS) requires accurate and consistent water quality monitoring to evaluate treatment efficiency and ensure regulatory compliance. However, off-line parameters such as chemical oxygen demand (COD), total suspended solids (TSS), and <i>Escherichia coli</i> (<i>E. coli</i>) require sample collection and time-consuming laboratory analyses that do not provide real-time information of system performance or component failure. While real-time COD analyzers have emerged in recent years, they are not economically viable for onsite systems due to cost and chemical consumables. This study aimed to design and implement a real-time remote monitoring system for OWTS by developing several multi-input and single-output soft sensors. The soft sensor integrates data that can be obtained from well-established in-line sensors to accurately predict key water quality parameters, including COD, TSS, and <i>E. coli</i> concentrations. The temporal and spatial water quality data of an existing field-tested OWTS operated for almost two years (<i>n</i> = 56 data points) were used to evaluate the prediction performance of four machine learning algorithms. These algorithms, namely, partial least square regression (PLS), support vector regression (SVR), cubist regression (CUB), and quantile regression neural network (QRNN), were chosen as candidate algorithms for their prior application and effectiveness in wastewater treatment predictions. Water quality parameters that can be measured in-line, including turbidity, color, pH, NH₄⁺, NO₃^–, and electrical conductivity, were selected as model inputs for predicting COD, TSS, and <i>E. coli</i>. The results revealed that the trained SVR model provided a statistically significant prediction for COD with a mean absolute percentage error (MAPE) of 14.5% and <i>R</i>² of 0.96. The CUB model provided the optimal predictive performance for TSS, with a MAPE of 24.8% and <i>R</i>² of 0.99. None of the models were able to achieve optimal prediction results for <i>E. coli</i>; however, the CUB model performed the best with a MAPE of 71.4% and <i>R</i>² of 0.22. Given the large fluctuation in the concentrations of COD, TSS, and <i>E. coli</i> within the OWTS wastewater dataset, the proposed soft sensor models adequately predicted COD and TSS, while <i>E. coli</i> prediction was comparatively less accurate and requires further improvement. These results indicate that although water quality datasets for the OWTS are relatively small, machine learning-based soft sensors can provide useful predictive estimates of off-line parameters and provide real-time monitoring capabilities that can be used to make adjustments to OWTS operations.</p>","PeriodicalId":29801,"journal":{"name":"ACS Environmental Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsenvironau.2c00072","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41158195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Direct Air Capture of CO2 Using Amine/Alumina Sorbents at Cold Temperature","authors":"Pranjali Priyadarshini,&nbsp;Guanhe Rim,&nbsp;Cornelia Rosu,&nbsp;MinGyu Song and Christopher W. Jones*,&nbsp;","doi":"10.1021/acsenvironau.3c00010","DOIUrl":"https://doi.org/10.1021/acsenvironau.3c00010","url":null,"abstract":"<p >Rising CO₂ emissions are responsible for increasing global temperatures causing climate change. Significant efforts are underway to develop amine-based sorbents to directly capture CO₂ from air (called direct air capture (DAC)) to combat the effects of climate change. However, the sorbents’ performances have usually been evaluated at ambient temperatures (25 °C) or higher, most often under dry conditions. A significant portion of the natural environment where DAC plants can be deployed experiences temperatures below 25 °C, and ambient air always contains some humidity. In this study, we assess the CO₂ adsorption behavior of amine (poly(ethyleneimine) (PEI) and tetraethylenepentamine (TEPA)) impregnated into porous alumina at ambient (25 °C) and cold temperatures (−20 °C) under dry and humid conditions. CO₂ adsorption capacities at 25 °C and 400 ppm CO₂ are highest for 40 wt% TEPA-incorporated γ-Al₂O₃ samples (1.8 mmol CO₂/g sorbent), while 40 wt % PEI-impregnated γ-Al₂O₃ samples exhibit moderate uptakes (0.9 mmol g^–1). CO₂ capacities for both PEI- and TEPA-incorporated γ-Al₂O₃ samples decrease with decreasing amine content and temperatures. The 40 and 20 wt % TEPA sorbents show the best performance at −20 °C under dry conditions (1.6 and 1.1 mmol g^–1, respectively). Both the TEPA samples also exhibit stable and high working capacities (0.9 and 1.2 mmol g^–1) across 10 cycles of adsorption–desorption (adsorption at −20 °C and desorption conducted at 60 °C). Introducing moisture (70% RH at −20 and 25 °C) improves the CO₂ capacity of the amine-impregnated sorbents at both temperatures. The 40 wt% PEI, 40 wt % TEPA, and 20 wt% TEPA samples show good CO₂ uptakes at both temperatures. The results presented here indicate that γ-Al₂O₃ impregnated with PEI and TEPA are potential materials for DAC at ambient and cold conditions, with further opportunities to optimize these materials for the scalable deployment of DAC plants at different environmental conditions.</p>","PeriodicalId":29801,"journal":{"name":"ACS Environmental Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsenvironau.3c00010","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49768526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Photocatalytic Conversion of Methane: Current State of the Art, Challenges, and Future Perspectives","authors":"Zhuo Liu,&nbsp;Biyang Xu,&nbsp;Yu-Jing Jiang,&nbsp;Yang Zhou,&nbsp;Xiaolian Sun,&nbsp;Yuanyuan Wang and Wenlei Zhu*,&nbsp;","doi":"10.1021/acsenvironau.3c00002","DOIUrl":"10.1021/acsenvironau.3c00002","url":null,"abstract":"<p >With 28–34 times the greenhouse effect of CO₂ over a 100-year period, methane is regarded as the second largest contributor to global warming. Reducing methane emissions is a necessary measure to limit global warming to below 1.5 °C. Photocatalytic conversion of methane is a promising approach to alleviate the atmospheric methane concentrations due to its low energy consumption and environmentally friendly characteristics. Meanwhile, this conversion process can produce valuable chemicals and liquid fuels such as CH₃OH, CH₃CH₂OH, C₂H₆, and C₂H₄, cutting down the dependence of chemical production on crude oil. However, the development of photocatalysts with a high methane conversion efficiency and product selectivity remains challenging. In this review, we overview recent advances in semiconductor-based photocatalysts for methane conversion and present catalyst design strategies, including morphology control, heteroatom doping, facet engineering, and cocatalysts modification. To gain a comprehensive understanding of photocatalytic methane conversion, the conversion pathways and mechanisms in these systems are analyzed in detail. Moreover, the role of electron scavengers in methane conversion performance is briefly discussed. Subsequently, we summarize the anthropogenic methane emission scenarios on earth and discuss the application potential of photocatalytic methane conversion. Finally, challenges and future directions for photocatalytic methane conversion are presented.</p>","PeriodicalId":29801,"journal":{"name":"ACS Environmental Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/9a/65/vg3c00002.PMC10515711.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41136826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of Photothermal Desorption-Compatible Diffusive Samplers for Volatile Organic Compounds","authors":"Jacob S. Shedd,&nbsp;Jonghwa Oh,&nbsp;Evan L. Floyd and Claudiu T. Lungu*,&nbsp;","doi":"10.1021/acsenvironau.2c00071","DOIUrl":"10.1021/acsenvironau.2c00071","url":null,"abstract":"<p >Products and starting materials containing volatile organic compounds (VOCs) can easily be found in a variety of businesses, making them a common source of occupational exposure. To prevent negative impacts on employee health, field industrial hygienists must conduct regular sampling to ensure exposures remain below the regulatory limits set by governmental and professional associations. As such, the need for sensitive and reliable exposure assessment techniques becomes evident. Over the preceding decade, the industrial hygiene research group at the University of Alabama at Birmingham (UAB) has been working on the development of an emerging, preanalytical technique known as photothermal desorption (PTD) to improve upon the analytical sensitivity of currently employed methods. PTD’s novel design uses pulses of high-energy light to desorb analytes from thermally conductive, carbonaceous sorbents, to be delivered to downstream analytical detectors. Since PTD’s conception, the theoretical framework and advances in sorbent fabrication have been investigated; however, further work is needed to produce a field-ready sampling device for use with PTD. As such, objectives of the present work were to design a PTD-compatible diffusive sampler prototype and characterize the prototype’s sampling efficiencies for toluene, <i>n</i>-hexane, trichloroethylene, and isopropyl alcohol. In pursuit of these objectives, the study empirically quantified the sampled masses of toluene, <i>n</i>-hexane, trichloroethylene, and isopropyl alcohol, at occupationally relevant air concentrations, to be 12.17 ± 0.06, 8.2 ± 0.1, 3.97 ± 0.06, and 8.0 ± 0.1 mg, respectively. Moreover, the analyte sampling efficiencies were found to be 2.2 ± 0.1, 1.7 ± 0.1, 1.2 ± 0.1, and 0.51 ± 0.05 (unitless) when comparing empirically (i.e., laboratory observed) sample mass values to theoretically predicted values. The sampling efficiencies and collected sample masses reported herein demonstrate the promising design of PTD-compatible diffusive samplers. When used in conjunction with the PTD method, the prototype samplers present strong evidence for improving analytical sensitivity in exposure assessments of VOCs in the workplace.</p>","PeriodicalId":29801,"journal":{"name":"ACS Environmental Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/e0/d6/vg2c00071.PMC10360198.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9862939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Use of a Dual-Labeled Bioaccumulation Method to Quantify Microplastic Vector Effects for Hydrophobic Organic Contaminants in Soil","authors":"Jie Wang*,&nbsp;Jianguo Tao,&nbsp;Jianghao Ji,&nbsp;Mochen Wu,&nbsp;Yuanze Sun,&nbsp;Jun Li* and Jay Gan,&nbsp;","doi":"10.1021/acsenvironau.3c00024","DOIUrl":"10.1021/acsenvironau.3c00024","url":null,"abstract":"<p >Although in vitro simulation and in vivo feeding experiments are commonly used to evaluate the carrier role of microplastics in the bioaccumulation of toxic chemicals, there is no direct method for quantitatively determining their vector effect. In this study, we propose a dual-labeled method based on spiking unlabeled hydrophobic organic contaminants (HOCs) into soils and spiking their respective isotope-labeled reference compounds into microplastic particles. The bioaccumulation of the unlabeled and isotope-labeled HOCs in <i>Eisenia fetida</i> earthworms was compared. Earthworms can assimilate both unlabeled and isotope-labeled HOCs via three routes: dermal uptake, soil ingestion, and microplastic ingestion. After 28 days of exposure, the relative fractions of bioaccumulated isotope-labeled HOCs in the soil treated with 1% microplastics ranged from 15.5 to 55.8%, which were 2.9–47.6 times higher than those in the soils treated with 0.1% microplastics. Polyethylene microplastics were observed to have higher relative fractions of bioaccumulated isotope-labeled HOCs, potentially because of their surface hydrophobicity and amorphous rubbery state. The general linear models suggested that the vector effects were mainly due to the microplastic concentration, followed by polymer properties and HOC hydrophobicity. This proposed method and the derived empirical formula contribute to a more comprehensive understanding of the vector effects of microplastics for HOC bioaccumulation.</p>","PeriodicalId":29801,"journal":{"name":"ACS Environmental Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/18/77/vg3c00024.PMC10360207.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10240087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Facing Global Climate and Environmental Change","authors":"Manabu Shiraiwa*,&nbsp;","doi":"10.1021/acsenvironau.3c00014","DOIUrl":"10.1021/acsenvironau.3c00014","url":null,"abstract":"G environmental change is real in the Anthropocene. Global warming is happening now, caused by anthropogenic activities with the emission of greenhouse gases. The latest reading of “the Keeling curve” has topped 424 ppm of carbon dioxide, which represents the highest record in continuous measurements of CO2 at Mauna Loa Observatory in Hawaii since 1960. Climate change has become more prominent and more evident that we experience it even in our daily life. Weather events have intensified with recordshattering climate extremes. This winter, we experienced record-breaking rainfall and snowfall associated with the atmospheric river in the West of the United States, while facing off against heat in the East of the United States. Biomass burning and wildfires have increased with higher frequency, longer durations, and longer seasons. Hurricanes have become more frequent and stronger, causing flooding in various places around the globe. These extreme events in a warming planet disrupt and negatively impact our society, restructuring our lifestyles in a myriad of ways, e.g., in sports: a recent study showed that global warming causes a reduction in ballpark air density, promoting more home runs in Major League Baseball games (bad news for pitchers!). Even though they are managed separately, climate change is coupled with air quality. There are cobenefits of climate regulations on improving air quality, but so far there is a lack of tools to rigorously evaluate the implications of addressing these challenges simultaneously. Sebastian D. Eastham and colleagues developed a computationally efficient approach to quantify how combined climate and air quality interventions affect air quality outcomes. Their approach captures spatial heterogeneity and complex atmospheric chemistry involving ozone, nitrogen oxides, volatile organic compounds, ammonia, and particulate matter, enabling rapid assessments modeling air quality−climate interactions. They demonstrate that air quality impact of climate policy depends on precursor emission stringency. In addition to greenhouse gases, particulate matter containing chromophores, so-called brown carbon, affects the climate by posing positive radiative forcing and serving as cloud condensation nuclei (CCN). The chemical composition and climate-relevant properties of brown carbon are highly dynamic, as they evolve upon chemical transformation in the atmosphere. Borduas-Dedekind and colleagues tackle this problem by irradiating lab-generated and field-collected brown carbon samples. They specifically focused on investigating photomineralization, a photodegradation process that fragments organic molecules to CO and CO2. They found that the rates of photomineralization were fastest for lab-generated samples and slowest for ambient brown carbon samples. Despite photobleaching and composition changes in the brown carbon, its CCN abilities did not change substantially. There are three more exciting publications in this issue. Kanel,","PeriodicalId":29801,"journal":{"name":"ACS Environmental Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/57/71/vg3c00014.PMC10266710.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10029377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unlocking High-Efficiency Methane Oxidation with Bimetallic Pd–Ce Catalysts under Zeolite Confinement","authors":"Xiaomai Chen,&nbsp;Xuefeng Shi,&nbsp;Peirong Chen,&nbsp;Bowen Liu,&nbsp;Meiyin Liu,&nbsp;Longwen Chen,&nbsp;Daiqi Ye,&nbsp;Xin Tu*,&nbsp;Wei Fan* and Junliang Wu*,&nbsp;","doi":"10.1021/acsenvironau.3c00008","DOIUrl":"10.1021/acsenvironau.3c00008","url":null,"abstract":"<p >Catalytic complete oxidation is an efficient approach to reducing methane emissions, a significant contributor to global warming. This approach requires active catalysts that are highly resistant to sintering and water vapor. In this work, we demonstrate that Pd nanoparticles confined within silicalite-1 zeolites (Pd@S-1), fabricated using a facile in situ encapsulation strategy, are highly active and stable in catalyzing methane oxidation and are superior to those supported on the S-1 surface due to a confinement effect. The activity of the confined Pd catalysts was further improved by co-confining a suitable amount of Ce within the S-1 zeolite (PdCe_0.4@S-1), which is attributed to confinement-reinforced Pd–Ce interactions that promote the formation of oxygen vacancies and highly reactive oxygen species. Furthermore, the introduction of Ce improves the hydrophobicity of the S-1 zeolite and, by forming Pd–Ce mixed oxides, inhibits the transformation of the active PdO phase to inactive Pd(OH)₂ species. Overall, the bimetallic PdCe_0.4@S-1 catalyst delivers exceptional outstanding activity and durability in complete methane oxidation, even in the presence of water vapor. This study may provide new prospects for the rational design of high-performance and durable Pd catalysts for complete methane oxidation.</p>","PeriodicalId":29801,"journal":{"name":"ACS Environmental Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsenvironau.3c00008","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10220847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advancing the Economic and Environmental Sustainability of the NEWgenerator Nonsewered Sanitation System","authors":"Shion Watabe,&nbsp;Hannah A. C. Lohman,&nbsp;Yalin Li,&nbsp;Victoria L. Morgan,&nbsp;Lewis S. Rowles,&nbsp;Tyler Stephen,&nbsp;Hsiang-Yang Shyu,&nbsp;Robert A. Bair,&nbsp;Cynthia J. Castro,&nbsp;Roland D. Cusick,&nbsp;Daniel H. Yeh and Jeremy S. Guest*,&nbsp;","doi":"10.1021/acsenvironau.3c00001","DOIUrl":"10.1021/acsenvironau.3c00001","url":null,"abstract":"<p >Achieving safely managed sanitation and resource recovery in areas that are rural, geographically challenged, or experiencing rapidly increasing population density may not be feasible with centralized facilities due to space requirements, site-specific concerns, and high costs of sewer installation. Nonsewered sanitation (NSS) systems have the potential to provide safely managed sanitation and achieve strict wastewater treatment standards. One such NSS treatment technology is the NEWgenerator, which includes an anaerobic membrane bioreactor (AnMBR), nutrient recovery via ion exchange, and electrochlorination. The system has been shown to achieve robust treatment of real waste for over 100 users, but the technology’s relative life cycle sustainability remains unclear. This study characterizes the financial viability and life cycle environmental impacts of the NEWgenerator and prioritizes opportunities to advance system sustainability through targeted improvements and deployment. The costs and greenhouse gas (GHG) emissions of the NEWgenerator (general case) leveraging grid electricity were 0.139 [0.113–0.168] USD cap^–1 day^–1 and 79.7 [55.0–112.3] kg CO₂-equiv cap^–1 year^–1, respectively. A transition to photovoltaic-generated electricity would increase costs to 0.145 [0.118–0.181] USD cap^–1 day^–1 but decrease GHG emissions to 56.1 [33.8–86.2] kg CO₂-equiv cap^–1 year^–1. The deployment location analysis demonstrated reduced median costs for deployment in China (−38%), India (−53%), Senegal (−31%), South Africa (−31%), and Uganda (−35%), but at comparable or increased GHG emissions (−2 to +16%). Targeted improvements revealed the relative change in median cost and GHG emissions to be −21 and −3% if loading is doubled (i.e., doubled users per unit), −30 and −12% with additional sludge drying, and +9 and −25% with the addition of a membrane contactor, respectively, with limited benefits (0–5% reductions) from an alternative photovoltaic battery, low-cost housing, or improved frontend operation. This research demonstrates that the NEWgenerator is a low-cost, low-emission NSS treatment technology with the potential for resource recovery to increase access to safe sanitation.</p>","PeriodicalId":29801,"journal":{"name":"ACS Environmental Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsenvironau.3c00001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9862942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Climate Change and the Sea: A Major Disruption in Steady State and the Master Variables","authors":"Reid A. Simmer,&nbsp;Emily J. Jansen,&nbsp;Kyle J. Patterson and Jerald L. Schnoor*,&nbsp;","doi":"10.1021/acsenvironau.2c00061","DOIUrl":"10.1021/acsenvironau.2c00061","url":null,"abstract":"<p >Since the beginning of the industrial revolution, humans have burned enormous quantities of coal, oil, and natural gas, rivaling nature’s elemental cycles of C, N, and S. The result has been a disruption in a steady state of CO₂ and other greenhouse gases in the atmosphere, a warming of the planet, and changes in master variables (temperature, pH, and pε) of the sea affecting critical physical, chemical, and biological reactions. Humans have also produced copious quantities of N and P fertilizers producing widespread coastal hypoxia and low dissolved oxygen conditions, which now threaten even the open ocean. Consequently, our massive alteration of state variables diminishes coral reefs, fisheries, and marine ecosystems, which are the foundation of life on Earth. We point to a myriad of actions and alternatives which will help to stem the tide of climate change and its effects on the sea while, at the same time, creating a more sustainable future for humans and ecosystems alike.</p>","PeriodicalId":29801,"journal":{"name":"ACS Environmental Au","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/epdf/10.1021/acsenvironau.2c00061","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9862941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}