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Synthesis, Adsorption Isotherm and Kinetic Study of Alkaline- Treated Zeolite/Chitosan/Fe 3+ Composites for Nitrate Removal from Aqueous Solution-Anion and Dye Effects. Gels 2022; 8:gels8120782. [PMID: 36547306 PMCID: PMC9777915 DOI: 10.3390/gels8120782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 11/25/2022] [Accepted: 11/26/2022] [Indexed: 12/02/2022] Open
Abstract
In the present study, alkaline-treated zeolite/chitosan/Fe3+ (ZLCH-Fe) composites were prepared and analyzed using scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR) and pH of zero point of charge (pHzpc) to remove nitrates from water. The process was carried out using an adsorption method with a varied initial pH, adsorbent dosage, initial nitrate concentration and contact time. The pHzpc demonstrated that the ZLCH-Fe surface had a positive charge between 2 and 10, making it easier to capture the negative charge of nitrate. However, the optimal pH value is 7. After 270 min, the maximum adsorption capacity and percent removal reached 498 mg/g and 99.64%, respectively. Freundlich and pseudo-second-order were fitted to the adsorption isotherm and kinetic models, respectively. An evaluation was conducted on the effects of anions-SO42- and PO43--and dyes-methylene blue (MB) and acid red 88 (AR88)-upon nitrate removal. The results indicated that the effect of the anion could be inhibited, in contrast to dye effects. However, the optimal pH values were changed to 10 for MB and 2 for AR88, resulting in a hydrogel formation. This might be indicated by the protonation of hydroxyl and amino groups resulting from a chitosan nitrate reaction in the AR88 solution.
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Detangling Seasonal Relationships of Fecal Contamination Sources and Correlates with Indicators in Michigan Watersheds. Microbiol Spectr 2022; 10:e0041522. [PMID: 35730960 PMCID: PMC9431008 DOI: 10.1128/spectrum.00415-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Despite the widely acknowledged public health impacts of surface water fecal contamination, there is limited understanding of seasonal effects on (i) fate and transport processes and (ii) the mechanisms by which they contribute to water quality impairment. Quantifying relationships between land use, chemical parameters, and fecal bacterial concentrations in watersheds can help guide the monitoring and control of microbial water quality and explain seasonal differences. The goals of this study were to (i) identify seasonal differences in Escherichia coli and Bacteroides thetaiotaomicron concentrations, (ii) evaluate environmental drivers influencing microbial contamination during baseflow, snowmelt, and summer rain seasons, and (iii) relate seasonal changes in B. thetaiotaomicron to anticipated gastrointestinal infection risks. Water chemistry data collected during three hydroclimatic seasons from 64 Michigan watersheds were analyzed using seasonal linear regression models with candidate variables including crop and land use proportions, prior precipitation, chemical parameters, and variables related to both wastewater treatment and septic usage. Adaptive least absolute shrinkage and selection operator (LASSO) linear regression with bootstrapping was used to select explanatory variables and estimate coefficients. Regardless of season, wastewater treatment plant and septic system usage were consistently selected in all primary models for B. thetaiotaomicron and E. coli. Chemistry and precipitation-related variable selection depended upon season and organism. These results suggest a link between human pollution (e.g., septic systems) and microbial water quality that is dependent on flow regime. IMPORTANCE In this study, a data set of 64 Michigan watersheds was utilized to gain insights into fecal contamination sources, drivers, and chemical correlates across seasons for general E. coli and human-specific fecal indicators. Results reaffirmed a link between human-specific sources (e.g., septic systems) and microbial water quality. While the importance of human sources of fecal contamination and fate and transport variables (e.g., precipitation) remain important across seasons, this study provides evidence that fate and transport mechanisms vary with seasonal hydrologic condition and microorganism source. This study contributes to a body of research that informs prioritization of fecal contamination source control and surveillance strategy development to reduce the public health burden of surface water fecal contamination.
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Monitoring coliphages to reduce waterborne infectious disease transmission in the One Water framework. Int J Hyg Environ Health 2022; 240:113921. [DOI: 10.1016/j.ijheh.2022.113921] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 12/31/2021] [Accepted: 01/05/2022] [Indexed: 02/07/2023]
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Evaluating Fecal Indicator and Pathogen Relationships in Sewage Impacted Surface Waters to Blend with Reclaimed Water for Potable Reuse in North Carolina. Pathogens 2021; 10:pathogens10121603. [PMID: 34959559 PMCID: PMC8705415 DOI: 10.3390/pathogens10121603] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 12/06/2021] [Accepted: 12/08/2021] [Indexed: 11/24/2022] Open
Abstract
Surface waters used for drinking water supply often receive upstream wastewater effluent inputs, resulting in de facto wastewater reuse for drinking water and recreation. As populations grow, demands on water supplies increase. As this trend continues, it creates the need to understand the risks associated with such reuse. In North Carolina, potable reuse has been proposed as a combination of at least 80% surface water with up to 20% tertiary-treated, dual-disinfected, reclaimed wastewater, which is then stored for 5 days and further treated using conventional drinking water treatment methods. The state of North Carolina has set standards for both intake surface water and for the reclaimed water produced by wastewater utilities, using indicator microorganisms to measure compliance. The goal of this study was to quantify fecal indicator microorganisms, specifically E. coli, coliphages, and C. perfringens as well as key pathogens, specifically Salmonella spp. bacteria, adenoviruses, noroviruses, and the protozoan parasites Cryptosporidium and Giardia, in two types of water representing potential candidates for potable reuse in North Carolina, (1) run of river surface water and (2) sewage-impacted surface waters, with the purpose of determining if there are predictive relationships between these two microorganism groups that support microbial indicator reliability.
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Runa V, Wenk J, Bengtsson S, Jones BV, Lanham AB. Bacteriophages in Biological Wastewater Treatment Systems: Occurrence, Characterization, and Function. Front Microbiol 2021; 12:730071. [PMID: 34803947 PMCID: PMC8600467 DOI: 10.3389/fmicb.2021.730071] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 08/25/2021] [Indexed: 12/20/2022] Open
Abstract
Phage bacteria interactions can affect structure, dynamics, and function of microbial communities. In the context of biological wastewater treatment (BWT), the presence of phages can alter the efficiency of the treatment process and influence the quality of the treated effluent. The active role of phages in BWT has been demonstrated, but many questions remain unanswered regarding the diversity of phages in these engineered environments, the dynamics of infection, the determination of bacterial hosts, and the impact of their activity in full-scale processes. A deeper understanding of the phage ecology in BWT can lead the improvement of process monitoring and control, promote higher influent quality, and potentiate the use of phages as biocontrol agents. In this review, we highlight suitable methods for studying phages in wastewater adapted from other research fields, provide a critical overview on the current state of knowledge on the effect of phages on structure and function of BWT bacterial communities, and highlight gaps, opportunities, and priority questions to be addressed in future research.
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Affiliation(s)
- Viviane Runa
- Centre for Sustainable and Circular Technologies, University of Bath, Bath, United Kingdom.,Department of Chemical Engineering, University of Bath, Bath, United Kingdom
| | - Jannis Wenk
- Department of Chemical Engineering, University of Bath, Bath, United Kingdom.,Water Innovation and Research Centre, University of Bath, Bath, United Kingdom
| | | | - Brian V Jones
- Department of Biology and Biochemistry, University of Bath, Bath, United Kingdom
| | - Ana B Lanham
- Centre for Sustainable and Circular Technologies, University of Bath, Bath, United Kingdom.,Department of Chemical Engineering, University of Bath, Bath, United Kingdom.,Water Innovation and Research Centre, University of Bath, Bath, United Kingdom
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Sobolik JS, Newman KL, Jaykus LA, Bihn EA, Leon JS. Norovirus transmission mitigation strategies during simulated produce harvest and packing. Int J Food Microbiol 2021; 357:109365. [PMID: 34488004 PMCID: PMC8510003 DOI: 10.1016/j.ijfoodmicro.2021.109365] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 08/04/2021] [Accepted: 08/15/2021] [Indexed: 02/07/2023]
Abstract
In the agricultural setting, core global food safety elements, such as hand hygiene and worker furlough, should reduce the risk of norovirus contamination on fresh produce. However, the effect of these practices has not been characterized. Using a quantitative microbial risk model, we evaluated the individual and combined effect of farm-based hand hygiene and worker furlough practices on the maximum risk of norovirus infection from three produce commodities (open leaf lettuce, vine tomatoes, and raspberries). Specifically, we tested two scenarios where a harvester's and packer's norovirus infection status was: 1) assumed positive; or 2) assigned based on community norovirus prevalence estimates. In the first scenario with a norovirus-positive harvester and packer, none of the individual interventions modeled reduced produce contamination to below the norovirus infectious dose. However, combined interventions, particularly high handwashing compliance (100%) and efficacy (6 log10 virus removal achieved using soap and water for 30 s), reduced produce contamination to <1-82 residual virus. Translating produce contamination to maximum consumer infection risk, 100% handwashing with a 5 log10 virus removal was necessary to achieve an infection risk below the threshold of 0.032 infections per consumption event. When community-based norovirus prevalence estimates were applied to the harvester and packer, the single interventions of 100% handwashing with 3 log10 virus removal (average 0.02 infection risk per consumption event) or furlough of the packer (average 0.03 infection risk per consumption event) reduced maximum infection risk to below the 0.032 threshold for all commodities. Bundled interventions (worker furlough, 100% glove compliance, and 100% handwashing with 1-log10 virus reduction) resulted in a maximum risk of 0.02 per consumption event across all commodities. These results advance the evidence-base for global produce safety standards as effective norovirus contamination and risk mitigation strategies.
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Affiliation(s)
- Julia S Sobolik
- Emory University, Gangarosa Department of Environmental Health, Atlanta, GA 30322, USA.
| | - Kira L Newman
- Emory University, Hubert Department of Global Health, Atlanta, GA 30322, USA
| | - Lee-Ann Jaykus
- North Carolina State University, Food, Bioprocessing, & Nutrition Sciences, Raleigh, NC 27695, USA
| | - Elizabeth A Bihn
- Cornell University, Department of Food Science, Ithaca, NY 14853, USA
| | - Juan S Leon
- Emory University, Hubert Department of Global Health, Atlanta, GA 30322, USA
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Sobolik JS, Sajewski ET, Jaykus LA, Cooper DK, Lopman BA, Kraay ANM, Ryan PB, Guest JL, Webb-Girard A, Leon JS. Low risk of SARS-CoV-2 transmission via fomite, even in cold-chain. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2021:2021.08.23.21262477. [PMID: 34462753 PMCID: PMC8404890 DOI: 10.1101/2021.08.23.21262477] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
BACKGROUND Countries continue to debate the need for decontamination of cold-chain food packaging to reduce possible SARS-CoV-2 fomite transmission among workers. While laboratory-based studies demonstrate persistence of SARS-CoV-2 on surfaces, the likelihood of fomite-mediated transmission under real-life conditions is uncertain. METHODS Using a quantitative risk assessment model, we simulated in a frozen food packaging facility 1) SARS-CoV-2 fomite-mediated infection risks following worker exposure to contaminated plastic packaging; and 2) reductions in these risks attributed to masking, handwashing, and vaccination. FINDINGS In a representative facility with no specific interventions, SARS-CoV-2 infection risk to a susceptible worker from contact with contaminated packaging was 2·8 × 10 -3 per 1h-period (95%CI: 6·9 × 10 -6 , 2·4 × 10 -2 ). Implementation of standard infection control measures, handwashing and masks (9·4 × 10 -6 risk per 1h-period, 95%CI: 2·3 × 10 -8 , 8·1 × 10 -5 ), substantially reduced risk (99·7%). Vaccination of the susceptible worker (two doses Pfizer/Moderna, vaccine effectiveness: 86-99%) combined with handwashing and masking reduced risk to less than 1·0 × 10 -6 . Simulating increased infectiousness/transmissibility of new variants (2-, 10-fold viral shedding) among a fully vaccinated workforce, handwashing and masks continued to mitigate risk (2·0 × 10 -6 -1·1 × 10 -5 risk per 1h-period). Decontamination of packaging in addition to these interventions reduced infection risks to below the 1·0 × 10 -6 risk threshold. INTERPRETATION Fomite-mediated SARS-CoV-2 infection risks were very low under cold-chain conditions. Handwashing and masking provide significant protection to workers, especially when paired with vaccination. FUNDING U.S. Department of Agriculture.
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Affiliation(s)
- Julia S. Sobolik
- Rollins School of Public Health, Emory University, Atlanta, GA, USA, 30322
| | | | - Lee-Ann Jaykus
- Food, Bioprocessing and Nutrition Sciences, North Carolina State University, Raleigh, NC, USA, 27695
| | - D. Kane Cooper
- Rollins School of Public Health, Emory University, Atlanta, GA, USA, 30322
| | - Ben A. Lopman
- Rollins School of Public Health, Emory University, Atlanta, GA, USA, 30322
| | - Alicia NM. Kraay
- Rollins School of Public Health, Emory University, Atlanta, GA, USA, 30322
| | - P. Barry Ryan
- Rollins School of Public Health, Emory University, Atlanta, GA, USA, 30322
| | - Jodie L. Guest
- Rollins School of Public Health, Emory University, Atlanta, GA, USA, 30322
| | - Amy Webb-Girard
- Rollins School of Public Health, Emory University, Atlanta, GA, USA, 30322
| | - Juan S. Leon
- Rollins School of Public Health, Emory University, Atlanta, GA, USA, 30322
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Truchado P, Garre A, Gil MI, Simón-Andreu PJ, Sánchez G, Allende A. Monitoring of human enteric virus and coliphages throughout water reuse system of wastewater treatment plants to irrigation endpoint of leafy greens. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 782:146837. [PMID: 33839667 DOI: 10.1016/j.scitotenv.2021.146837] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 03/25/2021] [Accepted: 03/25/2021] [Indexed: 06/12/2023]
Abstract
One solution to current water scarcity is the reuse of treated wastewater. Water reuse systems have to be examined as a whole, including the efficacy of water-reclamation treatments and the operation steps from the wastewater inlet into the WWTP to the irrigation endpoint, including the irrigated crop. In this study, the monitoring of human enteric viruses and coliphages were assessed in two water reused systems. The presence of hepatitis A virus (HAV) and human noroviruses genogroups I and II (GI and GII) were analyzed by real-time RT-PCR (RT-qPCR) in water (n = 475) and leafy green samples (n = 95). Total coliphages were analyzed by the double-layer agar plaque technique. The prevalence of HAV in water samples was very low (c.a. 2%), mostly linked to raw sewage, while for leafy green samples, none was positive for HAV. In leafy greens, prevalence of norovirus was low (less than 5-6%). The highest reductions for norovirus were observed in samples taken from the water reservoirs used by the growers near the growing field. The virus die-off during water storage due to solar radiation could be considered as an additional improvement. Reclamation treatments significantly reduced the prevalence and the counts of noroviruses GI and GII and coliphages in reclaimed water. However, the coliphage reductions (c.a. 5 log) do not comply with the specifications included in the new European regulation on reclaimed water (≥6.0 log). Correlations between noroviruses GI and GII and coliphages were found only in positive samples with high concentrations (>4.5 log PFU/100 mL). A high percentage of samples (20-25%) negative for total coliphages showed moderate norovirus counts (1-3 logs), indicating that coliphages are not the most suitable indicator for the possible presence of human enteric viruses.
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Affiliation(s)
- Pilar Truchado
- Research Group on Quality and Safety of Fruits and Vegetables, Department of Food Science and Technology, CEBAS-CSIC, Campus Universitario de Espinardo, 25, 30100 Murcia, Spain.
| | - Alberto Garre
- Food Microbiology, Wageningen University & Research, P.O. Box 17, 6700 AA Wageningen, the Netherlands
| | - Maria I Gil
- Research Group on Quality and Safety of Fruits and Vegetables, Department of Food Science and Technology, CEBAS-CSIC, Campus Universitario de Espinardo, 25, 30100 Murcia, Spain
| | - Pedro J Simón-Andreu
- Entidad Regional de Saneamiento y Depuración de Murcia (ESAMUR), Avda. Juan Carlos I, s/n. Ed. Torre Jemeca, 30009 Murcia, Spain
| | - Gloria Sánchez
- Department of Preservation and Food Safety Technologies, Institute of Agrochemistry and Food Technology, IATA-CSIC, Av. Agustín Escardino 7, Paterna 46980, Valencia, Spain
| | - Ana Allende
- Research Group on Quality and Safety of Fruits and Vegetables, Department of Food Science and Technology, CEBAS-CSIC, Campus Universitario de Espinardo, 25, 30100 Murcia, Spain
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Li X, Kelty CA, Sivaganesan M, Shanks OC. Variable fecal source prioritization in recreational waters routinely monitored with viral and bacterial general indicators. WATER RESEARCH 2021; 192:116845. [PMID: 33508720 PMCID: PMC8186395 DOI: 10.1016/j.watres.2021.116845] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 01/13/2021] [Accepted: 01/15/2021] [Indexed: 05/03/2023]
Abstract
Somatic and F+ coliphage methods are under consideration as potential routine surface water quality monitoring tools to identify unsafe levels of fecal pollution in recreational waters. However, little is known about the cooccurrence of these virus-based fecal indicators and host-associated genetic markers used to prioritize key pollution sources for remediation. In this study, paired measurements of cultivated coliphage (somatic and F+) and bacterial (E. coli and enterococci) general fecal indicators and genetic markers indicative of human (HF183/BacR287 and HumM2), ruminant (Rum2Bac), canine (DG3), and avian (GFD) fecal pollution sources were assessed in 365 water samples collected from six Great Lakes Basin beach and river sites over a 15-week recreational season. Water samples were organized into groups based on defined viral and bacterial fecal indicator water quality thresholds and average log10 host-associated genetic marker fecal score ratios were estimated to compare pollutant source inferences based on variable routine water quality monitoring practices. Eligible log10 fecal score ratios ranged from -0.051 (F+ coliphage, GFD) to 2.08 (enterococci, Rum2Bac). Using a fecal score ratio approach, findings suggest that general fecal indicator selection for routine water quality monitoring can influence the interpretation of host-associated genetic marker measurements, in some cases, prioritizing different pollutant sources for remediation. Variable trends were also observed between Great Lake beach and river sites suggesting disparate management practices may be useful for each water type.
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Affiliation(s)
- Xiang Li
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, China 518055
| | - Catherine A Kelty
- U.S. Environmental Protection Agency, Office of Research and Development, Cincinnati, OH, USA
| | - Mano Sivaganesan
- U.S. Environmental Protection Agency, Office of Research and Development, Cincinnati, OH, USA
| | - Orin C Shanks
- U.S. Environmental Protection Agency, Office of Research and Development, Cincinnati, OH, USA.
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Schoen ME, Boehm AB, Soller J, Shanks OC. Contamination Scenario Matters when Using Viral and Bacterial Human-Associated Genetic Markers as Indicators of a Health Risk in Untreated Sewage-Impacted Recreational Waters. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:13101-13109. [PMID: 32969642 PMCID: PMC8215692 DOI: 10.1021/acs.est.0c02189] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Fecal pollution at beaches can pose a health risk to recreators. Quantitative microbial risk assessment (QMRA) is a tool to evaluate the use of candidate fecal indicators to signify a health risk from enteric pathogens in sewage-impacted waters. We extend the QMRA approach to model mixtures of sewage at different ages using genetic marker concentrations for human-associated crAssphage, Bacteroides spp., and polyomavirus in sewage samples from 49 wastewater facilities across the contiguous United States. Risk-based threshold (RBT) estimates varied across different mixture and sewage age scenarios. Fresh sewage RBT estimates were not always protective when aged sewage was present, and aged sewage RBT estimates often fell below the marker lower limit of quantification. Conservative RBT estimates of 9.3 × 102 and 9.1 × 103 (copies/100 mL) for HF183/BacR287 and CPQ_056, respectively, were predicted when fresh sewage was greater (by volume) than aged at the time of measurement. Conversely, genetic markers may not be effective indicators when aged sewage contributes the majority of pathogens, relative to fresh contamination, but minimal marker levels. Results highlight the utility of QMRA that incorporates pollutant age and mixture scenarios, the potential advantages of a crAssphage fecal indicator, and the potential influence of site-specific factors on estimating RBT values.
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Affiliation(s)
- Mary E Schoen
- Soller Environmental, LLC, 3022 King St., Berkeley, California 94703, United States
| | - Alexandria B Boehm
- Department of Civil and Environmental Engineering, Stanford University, Stanford, California 94305, United States
| | - Jeffrey Soller
- Soller Environmental, LLC, 3022 King St., Berkeley, California 94703, United States
| | - Orin C Shanks
- U.S. Environmental Protection Agency, Office of Research and Development, Martin Luther King Drive, Cincinnati, Ohio 45268, United States
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McNeill K, Novak PJ, Vikesland PJ. 2019 Best Papers published in the Environmental Science journals of the Royal Society of Chemistry. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2020; 22:860-862. [PMID: 32292989 DOI: 10.1039/d0em90014a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The Editors-in-Chief of the Environmental Science journals introduce the Best Papers of 2019.
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Affiliation(s)
- Kristopher McNeill
- Institute for Biogeochemistry and Pollutant Dynamics, ETH Zurich, Zurich, Switzerland.
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