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Hartfield J, Bird E, Liang Z. Effects of Organic Surface Contamination on the Mass Accommodation Coefficient of Water: A Molecular Dynamics Study. J Phys Chem B 2024; 128:585-595. [PMID: 38175820 DOI: 10.1021/acs.jpcb.3c06939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2024]
Abstract
The mass accommodation coefficient (MAC), a parameter that quantifies the possibility of a phase change to occur at a liquid-vapor interface, can strongly affect the evaporation and condensation rates at a liquid surface. Due to the various challenges in experimental determination of the MAC, molecular dynamics (MD) simulations have been widely used to study the MAC on liquid surfaces with no impurities or contaminations. However, experimental studies show that airborne hydrocarbons from various sources can adsorb on liquid surfaces and alter the liquid surface properties. In this work, therefore, we study the effects of organic surface contamination, which is immiscible with water, on the MAC of water by equilibrium and nonequilibrium MD simulations. The equilibrium MD simulation results show that the MAC decreases almost linearly with increasing surface coverage of the organic contaminants. With the MAC determined from EMD simulations, the nonequilibrium MD simulation results show that the Schrage equation, which has been proven to be accurate in predicting the evaporation/condensation rates on clean liquid surfaces, is also accurate in predicting the condensation rate at contaminated water surfaces. The key assumption about the molecular velocity distribution in the Schrage analysis is still valid for condensing vapor molecules near contaminated water surfaces. We also find that under nonequilibrium conditions the adsorption of the water vapor molecules on the organic surface results in an adsorption vapor flux near the contaminated water surface. When the water surface is almost fully covered by the model organic contaminants, the adsorption flux dominates over the water condensation flux and leads to a false prediction of the MAC from the Schrage equation.
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Affiliation(s)
- Jordan Hartfield
- Department of Mechanical and Aerospace Engineering, Missouri University of Science and Technology, Rolla, Missouri 65409, United States
| | - Eric Bird
- Department of Mechanical and Aerospace Engineering, Missouri University of Science and Technology, Rolla, Missouri 65409, United States
| | - Zhi Liang
- Department of Mechanical and Aerospace Engineering, Missouri University of Science and Technology, Rolla, Missouri 65409, United States
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Lange SS, Shrestha L, Nnoli N, Aniagu S, Rawat S, McCant D. Do shale oil and gas production activities impact ambient air quality? A comprehensive study of 12 years of chemical concentrations and well production data from the Barnett Shale region of Texas. ENVIRONMENT INTERNATIONAL 2023; 175:107930. [PMID: 37086492 DOI: 10.1016/j.envint.2023.107930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 03/14/2023] [Accepted: 04/11/2023] [Indexed: 05/03/2023]
Abstract
Starting around 2008, there was rapid expansion of oil and natural gas (ONG) production into more heavily populated areas within the Dallas-Fort Worth metroplex in the Barnett Shale region of Texas. This colocation raised concerns regarding the effect of ONG activities on chemical levels in the air. In the current study, we examined the potential impacts of ONG activity on the types and concentrations of chemicals in ambient air in the Barnett Shale. Volatile organic compound (VOC) concentrations from 6-12 years (2008-2019) of hourly ambient air monitoring data from 15 monitors (4 monitors had ≥ 10 years of data) were compared to several metrics of ONG activity (number of active wells, natural gas production, condensate production) within a 2-mile radius of each monitor. Monitoring sites were also classified into urban, suburban, and rural areas as a surrogate for nearby vehicular emission sources. Analyses of this huge dataset showed that both peak and mean chemical concentrations of lighter alkane hydrocarbons (e.g., ethane) were most impacted by the number of gas wells. Levels of heavier alkanes (e.g., pentane) were increased by condensate production and at monitors located in areas with greater urbanicity, and therefore higher vehicular emissions. The levels of unsaturated alkynes (e.g., ethylene) were entirely driven by urbanicity and were unaffected by nearby ONG activity. The same pattern was seen with the ratio of iso:n-pentane, which is contrary to the findings of others and suggests an area for future research. Aromatic hydrocarbons were impacted by multiple emissions sources and did not show the same patterns as non-aromatic VOCs. No VOC concentrations were at levels of concern for human health or odor based on comparison to Texas air monitoring comparison values. Overall, ONG activities impact air quality, but this must be evaluated in the context of other emission sources such as automobiles.
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Affiliation(s)
- Sabine S Lange
- Toxicology, Risk Assessment, and Research Division, Texas Commission on Environmental Quality, Austin, TX 78753, USA.
| | - Lalita Shrestha
- Formerly at the Texas Commission on Environmental Quality, Austin, TX 78753, USA
| | - Nnamdi Nnoli
- Toxicology, Risk Assessment, and Research Division, Texas Commission on Environmental Quality, Austin, TX 78753, USA
| | - Stanley Aniagu
- Toxicology, Risk Assessment, and Research Division, Texas Commission on Environmental Quality, Austin, TX 78753, USA
| | - Swati Rawat
- Formerly at the Texas Commission on Environmental Quality, Austin, TX 78753, USA
| | - Darrell McCant
- Toxicology, Risk Assessment, and Research Division, Texas Commission on Environmental Quality, Austin, TX 78753, USA
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Impact of Shale Gas Exploration and Exploitation Activities on the Quality of Ambient Air—The Case Study of Wysin, Poland. ATMOSPHERE 2022. [DOI: 10.3390/atmos13081228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
The continuous two-year monitoring of a set of air pollutants, as well as gases directly related to shale gas exploration processes (methane, non-methane hydrocarbons, carbon dioxide), was carried out at Stary Wiec village in the vicinity (1100 m) of the shale gas wells area in Wysin (Pomeranian voivodeship, north of Poland), covering the stages of preparation, drilling, hydrofracturing and closing of wells. The results of analysis of air pollution data from Stary Wiec and nearby urban and rural stations, over the period 2012–2017 (starting three years before preparations for hydraulic fracturing) indicated that Stary Wiec represents a clean rural environment with an average concentration of nitrogen oxides, carbon monoxide and particulate matter that is one of the lowest in the Pomeranian region. The aim of this study was to explore the range of potential impact of shale gas exploration on local ambient air quality. Analysis of dependence of the concentration level of pollutants on the wind direction indicated that during the drilling period, when the air was coming directly from the area of the wells, nitrogen oxide concentration increased by 13%. Increases of concentration during the hydro-fracturing period, recorded at the Stary Wiec station, were equal to 108%, 21%, 18%, 12%, 7%, 4%, 1% for nitrogen oxide, non-methane hydrocarbons, carbon monoxide, nitrogen dioxide, particulate matter, carbon dioxide and methane. The results of one-minute concentration values for the period 1–4 September 2016 showed a series of short peaks up to 7.45 ppm for methane and up to 3.03 ppm for non-methane hydrocarbons, being probably the result of operations carried out at the area of the wells.
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Abstract
This paper examines whether public perceptions of the claimed advantages and disadvantages of fracking are consistent with an evidence-based assessment of the claimed advantages and disadvantages. Public assessments are obtained from an internet-based opinion survey in 2014 in six states: California, Illinois, New York, Ohio, Pennsylvania, and Texas. The survey presented eleven advantages and eleven disadvantages of fracking derived from local media stories, from advocacy claims made by pro- or anti-fracking groups, and from think tank pieces. Then the respondents were asked to indicate their feelings about how important each claimed advantage and disadvantage was to their support of/opposition to fracking. Scientific assessments regarding the same claims are compiled from available peer-reviewed literature and evidence-based reviews. We classify each claim as either (a) supported by the weight of the available evidence, (b) not supported by the weight of the available evidence, or (c) there is inadequate evidence to assess it. We find less consistency with respect to the disadvantages than advantages. Respondents perceive four disadvantages out of eleven as extremely important while there is inadequate evidence to assess them or the available evidence does not support them. Our comparison has interesting implications for understanding the controversy about fracking.
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Chan E, Worthy DEJ, Chan D, Ishizawa M, Moran MD, Delcloo A, Vogel F. Eight-Year Estimates of Methane Emissions from Oil and Gas Operations in Western Canada Are Nearly Twice Those Reported in Inventories. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:14899-14909. [PMID: 33169990 DOI: 10.1021/acs.est.0c04117] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The provinces of Alberta and Saskatchewan account for 70% of Canada's methane emissions from the oil and gas sector. In 2018, the Government of Canada introduced methane regulations to reduce emissions from the sector by 40-45% from the 2012 levels by 2025. Complementary to inventory accounting methods, the effectiveness of regulatory practices to reduce emissions can be assessed using atmospheric measurements and inverse models. Total anthropogenic (oil and gas, agriculture, and waste) emission rates of methane from 2010 to 2017 in Alberta and Saskatchewan were derived using hourly atmospheric methane measurements over a six-month winter period from October to March. Scaling up the winter estimate to annual indicated an anthropogenic emission rate of 3.7 ± 0.7 MtCH4/year, about 60% greater than that reported in Canada's National Inventory Report (2.3 MtCH4). This discrepancy is tied primarily to the oil and gas sector emissions as the reported emissions from livestock operations (0.6 MtCH4) are well substantiated in both top-down and bottom-up estimates and waste management (0.1 MtCH4) emissions are small. The resulting estimate of 3.0 MtCH4 from the oil and gas sector is nearly twice that reported in Canada's National Inventory (1.6 MtCH4).
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Affiliation(s)
- Elton Chan
- Climate Research Division, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Douglas E J Worthy
- Climate Research Division, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Douglas Chan
- Climate Research Division, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Misa Ishizawa
- Climate Research Division, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Michael D Moran
- Air Quality Research Division, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
| | - Andy Delcloo
- Royal Meteorological Institute of Belgium, B-1180 Ukkel, Brussels, Belgium
| | - Felix Vogel
- Climate Research Division, Environment and Climate Change Canada, Toronto, Ontario M3H 5T4, Canada
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O3 Sensitivity and Contributions of Different NMHC Sources in O3 Formation at Urban and Suburban Sites in Shanghai. ATMOSPHERE 2020. [DOI: 10.3390/atmos11030295] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Ground-level ozone (O3) pollution is still one of the priorities and challenges for air pollution control in the Yangtze River Delta (YRD) region of China. Understanding the relationship of O3 with its precursors and contributions of different sources in O3 formation is essential for the development of an O3 control strategy. This study analyzed O3 sensitivity to its precursors using a box model based on online observations of O3, non-methane hydrocarbons (NMHCs), nitrogen oxides (NOx), and carbon monoxide (CO) at an urban site and a suburban site in Shanghai in July 2017. Anthropogenic sources of NMHCs were identified using the positive matrix factorization (PMF) receptor model, and then contributions of different sources in O3 formation were estimated by the observation-based model (OBM). The relative incremental reactivity (RIR) values calculated by the OBM suggest that O3 formation at the urban site was in the NMHC-limited regime, while O3 formation at the suburban site tended between the transition regime and the NMHC-limited regime. Vehicular emission and liquefied petrochemical gas (LPG) use or aged air mass were found to be the two largest contributors at the urban and suburban sites in July, followed by paint and solvent use, and the petrochemical industry. However, from the perspective of O3 formation, vehicular emission and paint and solvent use were the largest two contributors at two sites due to the higher RIR values for paint and solvent use. In addition, the influence of transport on O3 sensitivity was identified by comparing O3 sensitivity at the suburban site across two days with different air mass paths. The result revealed that O3 formation in Shanghai is not only related to local emissions but also influenced by emissions from neighboring provinces. These findings on O3–NMHC–NOX sensitivity, contributions of different sources in O3 formation, and influence of transport could be useful for O3 pollution control in the YRD region. Nevertheless, more quantitative analyses on transport and further evaluation of the uncertainty of the OBM are still needed in future.
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Gorchov Negron AM, McDonald BC, McKeen SA, Peischl J, Ahmadov R, de Gouw JA, Frost GJ, Hastings MG, Pollack IB, Ryerson TB, Thompson C, Warneke C, Trainer M. Development of a Fuel-Based Oil and Gas Inventory of Nitrogen Oxides Emissions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:10175-10185. [PMID: 30071716 DOI: 10.1021/acs.est.8b02245] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In this study, we develop an alternative Fuel-based Oil and Gas inventory (FOG) of nitrogen oxides (NO x) from oil and gas production using publicly available fuel use records and emission factors reported in the literature. FOG is compared with the Environmental Protection Agency's 2014 National Emissions Inventory (NEI) and with new top-down estimates of NO x emissions derived from aircraft and ground-based field measurement campaigns. Compared to our top-down estimates derived in four oil and gas basins (Uinta, UT, Haynesville, TX/LA, Marcellus, PA, and Fayetteville, AR), the NEI overestimates NO x by over a factor of 2 in three out of four basins, while FOG is generally consistent with atmospheric observations. Challenges in estimating oil and gas engine activity, rather than uncertainties in NO x emission factors, may explain gaps between the NEI and top-down emission estimates. Lastly, we find a consistent relationship between reactive odd nitrogen species (NO y) and ambient methane (CH4) across basins with different geological characteristics and in different stages of production. Future work could leverage this relationship as an additional constraint on CH4 emissions from oil and gas basins.
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Affiliation(s)
- Alan M Gorchov Negron
- Department of Earth, Environmental, and Planetary Sciences , Brown University , Providence , Rhode Island 02912 , United States
| | - Brian C McDonald
- Cooperative Institute for Research in Environmental Sciences , University of Colorado , Boulder , Colorado 80309 , United States
- Chemical Sciences Division , NOAA Earth System Research Laboratory , Boulder , Colorado 80305 , United States
| | - Stuart A McKeen
- Cooperative Institute for Research in Environmental Sciences , University of Colorado , Boulder , Colorado 80309 , United States
- Chemical Sciences Division , NOAA Earth System Research Laboratory , Boulder , Colorado 80305 , United States
| | - Jeff Peischl
- Cooperative Institute for Research in Environmental Sciences , University of Colorado , Boulder , Colorado 80309 , United States
- Chemical Sciences Division , NOAA Earth System Research Laboratory , Boulder , Colorado 80305 , United States
| | - Ravan Ahmadov
- Cooperative Institute for Research in Environmental Sciences , University of Colorado , Boulder , Colorado 80309 , United States
- Global Systems Division , NOAA Earth System Research Laboratory , Boulder , Colorado 80305 , United States
| | - Joost A de Gouw
- Cooperative Institute for Research in Environmental Sciences , University of Colorado , Boulder , Colorado 80309 , United States
- Chemical Sciences Division , NOAA Earth System Research Laboratory , Boulder , Colorado 80305 , United States
| | - Gregory J Frost
- Chemical Sciences Division , NOAA Earth System Research Laboratory , Boulder , Colorado 80305 , United States
| | - Meredith G Hastings
- Department of Earth, Environmental, and Planetary Sciences , Brown University , Providence , Rhode Island 02912 , United States
| | - Ilana B Pollack
- Cooperative Institute for Research in Environmental Sciences , University of Colorado , Boulder , Colorado 80309 , United States
- Chemical Sciences Division , NOAA Earth System Research Laboratory , Boulder , Colorado 80305 , United States
| | - Thomas B Ryerson
- Chemical Sciences Division , NOAA Earth System Research Laboratory , Boulder , Colorado 80305 , United States
| | - Chelsea Thompson
- Cooperative Institute for Research in Environmental Sciences , University of Colorado , Boulder , Colorado 80309 , United States
- Chemical Sciences Division , NOAA Earth System Research Laboratory , Boulder , Colorado 80305 , United States
| | - Carsten Warneke
- Cooperative Institute for Research in Environmental Sciences , University of Colorado , Boulder , Colorado 80309 , United States
- Chemical Sciences Division , NOAA Earth System Research Laboratory , Boulder , Colorado 80305 , United States
| | - Michael Trainer
- Chemical Sciences Division , NOAA Earth System Research Laboratory , Boulder , Colorado 80305 , United States
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8
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Deng Y, Deng C, Yang J, Li B, Wang E, Yuan H. Novel Butane-Oxidizing Bacteria and Diversity of bmoX Genes in Puguang Gas Field. Front Microbiol 2018; 9:1576. [PMID: 30065710 PMCID: PMC6056644 DOI: 10.3389/fmicb.2018.01576] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 06/25/2018] [Indexed: 11/13/2022] Open
Abstract
To investigate the diversity of butane-oxidizing bacteria in soils contaminated by long-term light hydrocarbon microseepage and the influence of butane on the soil microbial community, a quantitative study and identification of butane-oxidizing bacteria (BOB) in soils at the Puguang gas field were performed by DNA-based stable isotope probing (DNA-SIP). For the first time, two phylotypes corresponding to the genera Giesbergeria and Ramlibacter were identified as being directly involved in butane oxidation, in addition to the well-known light hydrocarbon degrader Pseudomonas. Furthermore, bmoX genes were strongly labeled by 13C-butane, and their abundances in gas field soils increased by 43.14-, 17.39-, 21.74-, and 30.14-fold when incubated with butane for 6, 9, 12, and 14 days, respectively, indicating that these bmoX-harboring bacteria could use butane as the sole carbon and energy source and they play an important role in butane degradation. We also found that the addition of butane rapidly shaped the bacterial community and reduced the diversity of bmoX genes in the gas field soils. These findings improve our understanding of BOB in the gas field environment and reveal the potential for their applications in petroleum exploration and bioremediation.
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Affiliation(s)
- Yue Deng
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Chunping Deng
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Jinshui Yang
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Baozhen Li
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Entao Wang
- Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, Mexico City, Mexico
| | - Hongli Yuan
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
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Mo Z, Shao M, Wang W, Liu Y, Wang M, Lu S. Evaluation of biogenic isoprene emissions and their contribution to ozone formation by ground-based measurements in Beijing, China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 627:1485-1494. [PMID: 30857110 DOI: 10.1016/j.scitotenv.2018.01.336] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 01/27/2018] [Accepted: 01/31/2018] [Indexed: 06/09/2023]
Abstract
This study employs a mass balance technique-box model to calculate the biogenic isoprene emissions based on the ground-level measurements between October 2009 and September 2010 in Beijing. The annual magnitude, monthly variations and diurnal patterns of isoprene emissions are estimated. The annual emissions of isoprene were estimated to be 23.2Gg with an uncertainty of 120%. This falls within the range of previous emission inventories (EI; 3.8Gg to 36.3Gg between 1990 and 2010). Strong isoprene emissions were observed between May and September. The biggest difference was the isoprene emissions in May, with contributions of 23.3% to total annual emissions using box model estimates compared with 3.7% in EI. The diurnal profiles of isoprene emissions estimated in this study were generally similar to those in the EI, with the highest emissions occurring during mid-day (11:00-13:00). However, obvious differences were found for the growth rates and decreasing rates of isoprene emissions in the morning and afternoon respectively. Compared to anthropogenic volatile organic compounds (VOCs), the isoprene emissions contributed half (49.5%) of the total ozone formation potential (OFP) at 13:00 in August, which highlights the importance of isoprene in ozone formation. This study helps bound the isoprene emissions estimated by EI despite the inherent large uncertainty.
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Affiliation(s)
- Ziwei Mo
- Department of Mechanical Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Min Shao
- Institute for Environmental and Climate Research, Jinan University, Guangzhou 511443, China; State Joint Key Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
| | - Wenjie Wang
- State Joint Key Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Ying Liu
- State Joint Key Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China; Beijing Innovation Center for Engineering Science and Advanced Technology (BIC-ESAT), Peking University, Beijing 100871, China
| | - Ming Wang
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Nanjing University of Information Science & Technology, Nanjing 210044, China
| | - Sihua Lu
- State Joint Key Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
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Bolden AL, Schultz K, Pelch KE, Kwiatkowski CF. Exploring the endocrine activity of air pollutants associated with unconventional oil and gas extraction. Environ Health 2018; 17:26. [PMID: 29558955 PMCID: PMC5861625 DOI: 10.1186/s12940-018-0368-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 02/20/2018] [Indexed: 05/17/2023]
Abstract
BACKGROUND In the last decade unconventional oil and gas (UOG) extraction has rapidly proliferated throughout the United States (US) and the world. This occurred largely because of the development of directional drilling and hydraulic fracturing which allows access to fossil fuels from geologic formations that were previously not cost effective to pursue. This process is known to use greater than 1,000 chemicals such as solvents, surfactants, detergents, and biocides. In addition, a complex mixture of chemicals, including heavy metals, naturally-occurring radioactive chemicals, and organic compounds are released from the formations and can enter air and water. Compounds associated with UOG activity have been linked to adverse reproductive and developmental outcomes in humans and laboratory animal models, which is possibly due to the presence of endocrine active chemicals. METHODS Using systematic methods, electronic searches of PubMed and Web of Science were conducted to identify studies that measured chemicals in air near sites of UOG activity. Records were screened by title and abstract, relevant articles then underwent full text review, and data were extracted from the studies. A list of chemicals detected near UOG sites was generated. Then, the potential endocrine activity of the most frequently detected chemicals was explored via searches of literature from PubMed. RESULTS Evaluation of 48 studies that sampled air near sites of UOG activity identified 106 chemicals detected in two or more studies. Ethane, benzene and n-pentane were the top three most frequently detected. Twenty-one chemicals have been shown to have endocrine activity including estrogenic and androgenic activity and the ability to alter steroidogenesis. Literature also suggested that some of the air pollutants may affect reproduction, development, and neurophysiological function, all endpoints which can be modulated by hormones. These chemicals included aromatics (i.e., benzene, toluene, ethylbenzene, and xylene), several polycyclic aromatic hydrocarbons, and mercury. CONCLUSION These results provide a basis for prioritizing future primary studies regarding the endocrine disrupting properties of UOG air pollutants, including exposure research in wildlife and humans. Further, we recommend systematic reviews of the health impacts of exposure to specific chemicals, and comprehensive environmental sampling of a broader array of chemicals.
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Affiliation(s)
- Ashley L. Bolden
- The Endocrine Disruption Exchange (TEDX), www.TEDX.org, Eckert, Colorado USA
| | - Kim Schultz
- The Endocrine Disruption Exchange (TEDX), www.TEDX.org, Eckert, Colorado USA
| | - Katherine E. Pelch
- The Endocrine Disruption Exchange (TEDX), www.TEDX.org, Eckert, Colorado USA
| | - Carol F. Kwiatkowski
- The Endocrine Disruption Exchange (TEDX), www.TEDX.org, Eckert, Colorado USA
- Department of Integrative Physiology, University of Colorado, Boulder, Colorado USA
- Biological Sciences, North Carolina State University, Raleigh, North Carolina USA
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11
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Ghosh B. Impact of Changes in Oil and Gas Production Activities on Air Quality in Northeastern Oklahoma: Ambient Air Studies in 2015-2017. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:3285-3294. [PMID: 29439573 DOI: 10.1021/acs.est.7b05726] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A total of three ground-based ambient air studies were conducted in February through March of 2015, 2016, and 2017 at the Phillips 66 Research Center in northeastern Oklahoma. C2-C12 nonmethane hydrocarbons (NMHCs) were measured using whole-air sampling and gas chromatography-mass spectrometry. In 2016 and 2017, online methane and ethane measurements were also conducted. Strong methane-ethane correlation identified oil and gas (O&G) upstream and midstream operations to be the primary methane source. C2-C5 alkanes were the dominant NMHCs whose average mixing ratio peaked in 2016 before dropping in 2017. This observation is attributed to regional O&G upstream operations, which peaked in 2015. Mean mixing ratios of C2-C5 alkanes ranged from 0.99 to 16.99 ppb. Measured ratios of i-C5/ n-C5 were 0.97 ± 0.03, 1.18 ± 0.04, and 1.06 ± 0.02 in 2015, 2016, and 2017, respectively, indicating that O&G upstream and midstream operations were their primary source. Photochemical age was estimated using observed ratio between hexane and propane. Emission ratios of NMHCs at zero photochemical age were calculated, which resembled the composition reported in the literature for natural gas field condensate tank flashing. Back-trajectory analysis showed that hydrocarbon-rich plumes came from the south and west directions, where O&G upstream and midstream operations are abundant. High OH reactivity values were calculated from C2-C6 alkanes mixing ratios, with the average reactivity for the 3 years being 1.55, 1.88, and 1.16 s-1. This indicates that VOC emissions from O & G operations may contribute to ozone production.
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Affiliation(s)
- Buddhadeb Ghosh
- Phillips 66 Research Center , Highway 60 and 123, Bartlesville , Oklahoma 74003 , United States
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12
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Species-specified VOC emissions derived from a gridded study in the Pearl River Delta, China. Sci Rep 2018; 8:2963. [PMID: 29445109 PMCID: PMC5813039 DOI: 10.1038/s41598-018-21296-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 01/09/2018] [Indexed: 11/09/2022] Open
Abstract
This study provides a top-down approach to establish an emission inventory of volatile organic compounds (VOC) based on ambient measurements, by combining the box model and positive matrix factorization (PMF) model. Species-specified VOC emissions, source contributions, and spatial distributions are determined based on regional-scale gridded measurements between September 2008 to December 2009 in the Pearl River Delta (PRD), China. The most prevalent anthropogenic species in the PRD was toluene estimated by the box model to be annual emissions of 167.8 ± 100.5 Gg, followed by m,p-xylene (68.0 ± 45.0 Gg), i-pentane (49.2 ± 40.0 Gg), ethene (47.6 ± 27.6 Gg), n-butane (47.5 ± 40.7 Gg), and benzene (46.8 ± 29.0 Gg). Alkanes such as propane, i-butane, and n-pentane were 2-8 times higher in box model than emission inventories (EI). Species with fewer emissions were highly variable between EI and box model results. Hotspots of VOC emissions were identified in southwestern PRD and port areas, which were not reflected by bottom-up EI. This suggests more research is needed for VOC emissions in the EI, especially for fuel evaporation, industrial operations and marine vessels. The species-specified top-down method can help improve the quality of these emission inventories.
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Singh R, Guzman MS, Bose A. Anaerobic Oxidation of Ethane, Propane, and Butane by Marine Microbes: A Mini Review. Front Microbiol 2017; 8:2056. [PMID: 29109712 PMCID: PMC5660070 DOI: 10.3389/fmicb.2017.02056] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 10/06/2017] [Indexed: 12/16/2022] Open
Abstract
The deep ocean and its sediments are a continuous source of non-methane short-chain alkanes (SCAs) including ethane, propane, and butane. Their high global warming potential, and contribution to local carbon and sulfur budgets has drawn significant scientific attention. Importantly, microbes can use gaseous alkanes and oxidize them to CO2, thus acting as effective biofilters. A relative decrease of these gases with a concomitant 13C enrichment of propane and n-butane in interstitial waters vs. the source suggests microbial anaerobic oxidation. The reported uncoupling of sulfate-reduction (SR) from anaerobic methane oxidation supports their microbial consumption. To date, strain BuS5 isolated from the sediments of Guaymas Basin, Gulf of California, is the only pure culture that can anaerobically degrade propane and n-butane. This organism belongs to a metabolically diverse cluster within the Deltaproteobacteria called Desulfosarcina/Desulfococcus. Other phylotypes involved in gaseous alkane degradation were identified based on stable-isotope labeling and fluorescence in-situ hybridization. A novel syntrophic association of the archaeal genus, Candidatus Syntrophoarchaeum, and a thermophilic SR bacterium, HotSeep-1 was recently discovered from the Guaymas basin, Gulf of California that can anaerobically oxidize n-butane. Strikingly, metagenomic data and the draft genomes of ca. Syntrophoarchaeum suggest that this organism uses a novel mechanism for n-butane oxidation, distinct from the well-established fumarate addition mechanism. These recent findings indicate that a lot remains to be understood about our understanding of anaerobic SCA degradation. This mini-review summarizes our current understanding of microbial anaerobic SCA degradation, and provides an outlook for future research.
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Affiliation(s)
- Rajesh Singh
- Department of Biology, Washington University in St. Louis, St. Louis, MO, United States
| | - Michael S Guzman
- Department of Biology, Washington University in St. Louis, St. Louis, MO, United States
| | - Arpita Bose
- Department of Biology, Washington University in St. Louis, St. Louis, MO, United States
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Abstract
Cycloclasticus bacteria are ubiquitous in oil-rich
regions of the ocean and are known for their ability to degrade polycyclic
aromatic hydrocarbons (PAHs). In this study, we describe
Cycloclasticus that have established a symbiosis with
Bathymodiolus heckerae mussels and poecilosclerid sponges
from asphalt-rich, deep-sea oil seeps at Campeche Knolls in the southern Gulf of
Mexico. Genomic and transcriptomic analyses revealed that in contrast to all
known Cycloclasticus, the symbiotic
Cycloclasticus appeared to lack the genes needed for PAH
degradation. Instead, these symbionts use propane and other short-chain alkanes
such as ethane and butane as carbon and energy sources, thus expanding the
limited range of substrates known to power chemosynthetic symbioses. Analyses of
short-chain alkanes in the environment of the Campeche Knolls symbioses revealed
that these are present at high concentrations (in the µM to mM range).
Comparative genomic analyses revealed high similarities between the genes used
by the symbiotic Cycloclasticus to degrade short-chain alkanes
and those of free-living Cycloclasticus that bloomed during the
Deepwater Horizon (DWH) oil spill. Our results indicate that the metabolic
versatility of bacteria within the Cycloclasticus clade is
higher than previously assumed, and highlight the expanded role of these
keystone species in the degradation of marine hydrocarbons.
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Marrero JE, Townsend-Small A, Lyon DR, Tsai TR, Meinardi S, Blake DR. Estimating Emissions of Toxic Hydrocarbons from Natural Gas Production Sites in the Barnett Shale Region of Northern Texas. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:10756-10764. [PMID: 27580823 DOI: 10.1021/acs.est.6b02827] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Oil and natural gas operations have continued to expand and move closer to densely populated areas, contributing to growing public concerns regarding exposure to hazardous air pollutants. During the Barnett Shale Coordinated Campaign in October, 2013, ground-based whole air samples collected downwind of oil and gas sites revealed enhancements in several potentially toxic volatile organic compounds (VOCs) when compared to background values. Molar emissions ratios relative to methane were determined for hexane, benzene, toluene, ethylbenzene, and xylene (BTEX compounds). Using methane leak rates measured from the Picarro mobile flux plane (MFP) system and a Barnett Shale regional methane emissions inventory, the rates of emission of these toxic gases were calculated. Benzene emissions ranged between 51 ± 4 and 60 ± 4 kg h-1. Hexane, the most abundantly emitted pollutant, ranged from 642 ± 45 to 1070 ± 340 kg h-1. While observed hydrocarbon enhancements fall below federal workplace standards, results may indicate a link between emissions from oil and natural gas operations and concerns about exposure to hazardous air pollutants. The larger public health risks associated with the production and distribution of natural gas are of particular importance and warrant further investigation, particularly as the use of natural gas increases in the United States and internationally.
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Affiliation(s)
- Josette E Marrero
- NASA Ames Research Center, Moffett Field, California 94035, United States
| | - Amy Townsend-Small
- Departments of Geology and Geography, University of Cincinnati , Cincinnati, Ohio 45221, United States
| | - David R Lyon
- Environmental Defense Fund, Austin, Texas 78701, United States
| | - Tracy R Tsai
- Picarro, Inc., Santa Clara, California 95054, United States
| | - Simone Meinardi
- Department of Chemistry, University of California, Irvine , Irvine, California 92697, United States
| | - Donald R Blake
- Department of Chemistry, University of California, Irvine , Irvine, California 92697, United States
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16
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Sather ME, Cavender K. Trends analyses of 30 years of ambient 8 hour ozone and precursor monitoring data in the South Central U.S.: progress and challenges. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2016; 18:819-831. [PMID: 27282109 DOI: 10.1039/c6em00210b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
In the last 30 years ambient ozone concentrations have notably decreased in the South Central U.S. Yet, current ambient ozone concentrations measured over the past three years 2013-2015 in this area of the U.S. are not meeting the U.S. 2015 8 hour ozone standard of 70 parts per billion (ppb). This paper provides an update on long-term trends analyses of ambient 8 hour ozone and ozone precursor monitoring data collected over the past 30 years (1986-2015) in four South Central U.S. cities, following up on two previously published reviews of 20 and 25 year trends for these cities. All four cities have benefitted from national ozone precursor controls put in place during the 1990s and 2000s involving cleaner vehicles (vehicle fleet turnover/replacement over time), cleaner fuels, cleaner gasoline and diesel engines, and improved inspection/maintenance programs for existing vehicles. Additional ozone precursor emission controls specific to each city are detailed in this paper. The controls have resulted in impressive ambient ozone and ambient ozone precursor concentration reductions in the four South Central U.S. cities over the past 30 years, including 31-70% ambient nitrogen oxides (NOx) concentration declines from historical peaks to the present, 43-72% volatile organic compound (VOC) concentration declines from historical peaks to the present, a related 45-76% VOC reactivity decline for a subset of VOC species from historical peaks to the present, and an 18-38 ppb reduction in city 8 hour ozone design value concentrations. A new challenge for each of the four South Central U.S. cities will be meeting the U.S. 2015 8 hour ozone standard of 70 ppb.
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Affiliation(s)
- Mark E Sather
- Air Monitoring and Grants Section, U.S. EPA Region 6, 1445 Ross Avenue, Dallas, TX 75202, USA.
| | - Kevin Cavender
- Air Quality Assessment Division, U.S. EPA Office of Air Quality Planning and Standards, Mail Code C304-06, Research Triangle Park, NC 27711, USA
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17
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Zavala-Araiza D, Lyon DR, Alvarez RA, Davis KJ, Harriss R, Herndon SC, Karion A, Kort EA, Lamb BK, Lan X, Marchese AJ, Pacala SW, Robinson AL, Shepson PB, Sweeney C, Talbot R, Townsend-Small A, Yacovitch TI, Zimmerle DJ, Hamburg SP. Reconciling divergent estimates of oil and gas methane emissions. Proc Natl Acad Sci U S A 2015; 112:15597-602. [PMID: 26644584 PMCID: PMC4697433 DOI: 10.1073/pnas.1522126112] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Published estimates of methane emissions from atmospheric data (top-down approaches) exceed those from source-based inventories (bottom-up approaches), leading to conflicting claims about the climate implications of fuel switching from coal or petroleum to natural gas. Based on data from a coordinated campaign in the Barnett Shale oil and gas-producing region of Texas, we find that top-down and bottom-up estimates of both total and fossil methane emissions agree within statistical confidence intervals (relative differences are 10% for fossil methane and 0.1% for total methane). We reduced uncertainty in top-down estimates by using repeated mass balance measurements, as well as ethane as a fingerprint for source attribution. Similarly, our bottom-up estimate incorporates a more complete count of facilities than past inventories, which omitted a significant number of major sources, and more effectively accounts for the influence of large emission sources using a statistical estimator that integrates observations from multiple ground-based measurement datasets. Two percent of oil and gas facilities in the Barnett accounts for half of methane emissions at any given time, and high-emitting facilities appear to be spatiotemporally variable. Measured oil and gas methane emissions are 90% larger than estimates based on the US Environmental Protection Agency's Greenhouse Gas Inventory and correspond to 1.5% of natural gas production. This rate of methane loss increases the 20-y climate impacts of natural gas consumed in the region by roughly 50%.
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Affiliation(s)
| | | | | | | | | | | | - Anna Karion
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309; Earth System Research Laboratory, National Oceanic and Atmospheric Administration, Boulder, CO 80305
| | - Eric Adam Kort
- Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, MI 48109
| | - Brian K Lamb
- Department of Civil and Environmental Engineering, Washington State University, Pullman, WA 99163
| | - Xin Lan
- Department of Earth and Atmospheric Sciences, University of Houston, Houston, TX 77004
| | - Anthony J Marchese
- Department of Mechanical Engineering, Colorado State University, Fort Collins, CO 80523
| | - Stephen W Pacala
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544;
| | - Allen L Robinson
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213
| | - Paul B Shepson
- Department of Chemistry, Purdue University, West Lafayette, IN 47907
| | - Colm Sweeney
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309; Earth System Research Laboratory, National Oceanic and Atmospheric Administration, Boulder, CO 80305
| | - Robert Talbot
- Department of Earth and Atmospheric Sciences, University of Houston, Houston, TX 77004
| | | | | | - Daniel J Zimmerle
- Department of Mechanical Engineering, Colorado State University, Fort Collins, CO 80523
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18
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Lan X, Talbot R, Laine P, Torres A, Lefer B, Flynn J. Atmospheric Mercury in the Barnett Shale Area, Texas: Implications for Emissions from Oil and Gas Processing. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:10692-10700. [PMID: 26218013 DOI: 10.1021/acs.est.5b02287] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Atmospheric mercury emissions in the Barnett Shale area were studied by employing both stationary measurements and mobile laboratory surveys. Stationary measurements near the Engle Mountain Lake showed that the median mixing ratio of total gaseous mercury (THg) was 138 ppqv (140 ± 29 ppqv for mean ± S.D.) during the June 2011 study period. A distinct diurnal variation pattern was observed in which the highest THg levels appeared near midnight, followed by a monotonic decrease until midafternoon. The influence of oil and gas (ONG) emissions was substantial in this area, as inferred from the i-pentane/n-pentane ratio (1.17). However, few THg plumes were captured by our mobile laboratory during a ∼3700 km survey with detailed downwind measurements from 50 ONG facilities. One compressor station and one natural gas condensate processing facility were found to have significant THg emissions, with maximum THg levels of 963 and 392 ppqv, respectively, and the emissions rates were estimated to be 7.9 kg/yr and 0.3 kg/yr, respectively. Our results suggest that the majority of ONG facilities in this area are not significant sources of THg; however, it is highly likely that a small number of these facilities contribute a relatively large amount of emissions in the ONG sector.
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Affiliation(s)
- Xin Lan
- Institute for Climate and Atmospheric Science, Department of Earth and Atmospheric Sciences, University of Houston , Houston, Texas 77004, United States
| | - Robert Talbot
- Institute for Climate and Atmospheric Science, Department of Earth and Atmospheric Sciences, University of Houston , Houston, Texas 77004, United States
| | - Patrick Laine
- Institute for Climate and Atmospheric Science, Department of Earth and Atmospheric Sciences, University of Houston , Houston, Texas 77004, United States
| | - Azucena Torres
- Institute for Climate and Atmospheric Science, Department of Earth and Atmospheric Sciences, University of Houston , Houston, Texas 77004, United States
| | - Barry Lefer
- Institute for Climate and Atmospheric Science, Department of Earth and Atmospheric Sciences, University of Houston , Houston, Texas 77004, United States
| | - James Flynn
- Institute for Climate and Atmospheric Science, Department of Earth and Atmospheric Sciences, University of Houston , Houston, Texas 77004, United States
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19
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Townsend-Small A, Marrero JE, Lyon DR, Simpson IJ, Meinardi S, Blake DR. Integrating Source Apportionment Tracers into a Bottom-up Inventory of Methane Emissions in the Barnett Shale Hydraulic Fracturing Region. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:8175-82. [PMID: 26148556 DOI: 10.1021/acs.est.5b00057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
A growing dependence on natural gas for energy may exacerbate emissions of the greenhouse gas methane (CH4). Identifying fingerprints of these emissions is critical to our understanding of potential impacts. Here, we compare stable isotopic and alkane ratio tracers of natural gas, agricultural, and urban CH4 sources in the Barnett Shale hydraulic fracturing region near Fort Worth, Texas. Thermogenic and biogenic sources were compositionally distinct, and emissions from oil wells were enriched in alkanes and isotopically depleted relative to natural gas wells. Emissions from natural gas production varied in δ(13)C and alkane ratio composition, with δD-CH4 representing the most consistent tracer of natural gas sources. We integrated our data into a bottom-up inventory of CH4 for the region, resulting in an inventory of ethane (C2H6) sources for comparison to top-down estimates of CH4 and C2H6 emissions. Methane emissions in the Barnett are a complex mixture of urban, agricultural, and fossil fuel sources, which makes source apportionment challenging. For example, spatial heterogeneity in gas composition and high C2H6/CH4 ratios in emissions from conventional oil production add uncertainty to top-down models of source apportionment. Future top-down studies may benefit from the addition of δD-CH4 to distinguish thermogenic and biogenic sources.
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Affiliation(s)
- Amy Townsend-Small
- †University of Cincinnati, Departments of Geology and Geography, Cincinnati, Ohio 45221, United States
| | - Josette E Marrero
- ‡University of California, Irvine, Department of Chemistry, Irvine, California 92697, United States
| | - David R Lyon
- §Environmental Defense Fund, 301 Congress Ave., Suite 1300, Austin, Texas 78701, United States
| | - Isobel J Simpson
- ‡University of California, Irvine, Department of Chemistry, Irvine, California 92697, United States
| | - Simone Meinardi
- ‡University of California, Irvine, Department of Chemistry, Irvine, California 92697, United States
| | - Donald R Blake
- ‡University of California, Irvine, Department of Chemistry, Irvine, California 92697, United States
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20
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Lavoie TN, Shepson PB, Cambaliza MOL, Stirm BH, Karion A, Sweeney C, Yacovitch TI, Herndon SC, Lan X, Lyon D. Aircraft-Based Measurements of Point Source Methane Emissions in the Barnett Shale Basin. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:7904-7913. [PMID: 26148549 DOI: 10.1021/acs.est.5b00410] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We report measurements of methane (CH4) emission rates observed at eight different high-emitting point sources in the Barnett Shale, Texas, using aircraft-based methods performed as part of the Barnett Coordinated Campaign. We quantified CH4 emission rates from four gas processing plants, one compressor station, and three landfills during five flights conducted in October 2013. Results are compared to other aircraft- and surface-based measurements of the same facilities, and to estimates based on a national study of gathering and processing facilities emissions and 2013 annual average emissions reported to the U.S. EPA Greenhouse Gas Reporting Program (GHGRP). For the eight sources, CH4 emission measurements from the aircraft-based mass balance approach were a factor of 3.2-5.8 greater than the GHGRP-based estimates. Summed emissions totaled 7022 ± 2000 kg hr(-1), roughly 9% of the entire basin-wide CH4 emissions estimated from regional mass balance flights during the campaign. Emission measurements from five natural gas management facilities were 1.2-4.6 times larger than emissions based on the national study. Results from this study were used to represent "super-emitters" in a newly formulated Barnett Shale Inventory, demonstrating the importance of targeted sampling of "super-emitters" that may be missed by random sampling of a subset of the total.
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Affiliation(s)
- Tegan N Lavoie
- †Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Paul B Shepson
- †Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
- ‡Department of Earth, Atmospheric and Planetary Sciences and Purdue Climate Change Research Center, Purdue University, West Lafayette, Indiana 47907, United States
| | - Maria O L Cambaliza
- †Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Brian H Stirm
- §Department of Aviation Technology, Purdue University, West Lafayette, Indiana 47907, United States
| | - Anna Karion
- ∥CIRES, Boulder, Colorado 80309, United States
- ⊥NOAA Earth System Research Laboratory, Boulder, Colorado 80305, United States
| | - Colm Sweeney
- ∥CIRES, Boulder, Colorado 80309, United States
- ⊥NOAA Earth System Research Laboratory, Boulder, Colorado 80305, United States
| | - Tara I Yacovitch
- ∇Aerodyne Research, Inc., Billerica, Massachusetts 01821, United States
| | - Scott C Herndon
- ∇Aerodyne Research, Inc., Billerica, Massachusetts 01821, United States
| | - Xin Lan
- ◆Department of Earth and Atmospheric Sciences, University of Houston, Houston, Texas 77004, United States
| | - David Lyon
- ¶Environmental Defense Fund, Austin, Texas 78701, United States
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21
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Karion A, Sweeney C, Kort EA, Shepson PB, Brewer A, Cambaliza M, Conley SA, Davis K, Deng A, Hardesty M, Herndon SC, Lauvaux T, Lavoie T, Lyon D, Newberger T, Pétron G, Rella C, Smith M, Wolter S, Yacovitch TI, Tans P. Aircraft-Based Estimate of Total Methane Emissions from the Barnett Shale Region. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:8124-31. [PMID: 26148550 DOI: 10.1021/acs.est.5b00217] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
We present estimates of regional methane (CH4) emissions from oil and natural gas operations in the Barnett Shale, Texas, using airborne atmospheric measurements. Using a mass balance approach on eight different flight days in March and October 2013, the total CH4 emissions for the region are estimated to be 76 ± 13 × 10(3) kg hr(-1) (equivalent to 0.66 ± 0.11 Tg CH4 yr(-1); 95% confidence interval (CI)). We estimate that 60 ± 11 × 10(3) kg CH4 hr(-1) (95% CI) are emitted by natural gas and oil operations, including production, processing, and distribution in the urban areas of Dallas and Fort Worth. This estimate agrees with the U.S. Environmental Protection Agency (EPA) estimate for nationwide CH4 emissions from the natural gas sector when scaled by natural gas production, but it is higher than emissions reported by the EDGAR inventory or by industry to EPA's Greenhouse Gas Reporting Program. This study is the first to show consistency between mass balance results on so many different days and in two different seasons, enabling better quantification of the related uncertainty. The Barnett is one of the largest production basins in the United States, with 8% of total U.S. natural gas production, and thus, our results represent a crucial step toward determining the greenhouse gas footprint of U.S. onshore natural gas production.
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Affiliation(s)
- Anna Karion
- †University of Colorado, CIRES, Boulder, Colorado 80309, United States
- ‡NOAA Earth System Research Laboratory, Boulder 80305, Colorado, United States
| | - Colm Sweeney
- †University of Colorado, CIRES, Boulder, Colorado 80309, United States
- ‡NOAA Earth System Research Laboratory, Boulder 80305, Colorado, United States
| | - Eric A Kort
- §University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Paul B Shepson
- ∥Purdue University, West Lafayette, Indiana 47907, United States
| | - Alan Brewer
- ‡NOAA Earth System Research Laboratory, Boulder 80305, Colorado, United States
| | - Maria Cambaliza
- ∥Purdue University, West Lafayette, Indiana 47907, United States
| | - Stephen A Conley
- ⊥University of California, Davis, Davis, California 95616, United States
| | - Ken Davis
- #Carbon Now Cast, LLC, State College, Pennsylvania 16803, United States
| | - Aijun Deng
- #Carbon Now Cast, LLC, State College, Pennsylvania 16803, United States
| | - Mike Hardesty
- †University of Colorado, CIRES, Boulder, Colorado 80309, United States
- ‡NOAA Earth System Research Laboratory, Boulder 80305, Colorado, United States
| | - Scott C Herndon
- ∇Aerodyne Research, Inc., Billerica, Massachusetts 01821, United States
| | - Thomas Lauvaux
- #Carbon Now Cast, LLC, State College, Pennsylvania 16803, United States
| | - Tegan Lavoie
- ∥Purdue University, West Lafayette, Indiana 47907, United States
| | - David Lyon
- ○Environmental Defense Fund, Austin, Texas 78701, United States
| | - Tim Newberger
- †University of Colorado, CIRES, Boulder, Colorado 80309, United States
- ‡NOAA Earth System Research Laboratory, Boulder 80305, Colorado, United States
| | - Gabrielle Pétron
- †University of Colorado, CIRES, Boulder, Colorado 80309, United States
- ‡NOAA Earth System Research Laboratory, Boulder 80305, Colorado, United States
| | - Chris Rella
- ◆Picarro, Inc., Santa Clara, California 95054, United States
| | - Mackenzie Smith
- §University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Sonja Wolter
- †University of Colorado, CIRES, Boulder, Colorado 80309, United States
- ‡NOAA Earth System Research Laboratory, Boulder 80305, Colorado, United States
| | - Tara I Yacovitch
- ∇Aerodyne Research, Inc., Billerica, Massachusetts 01821, United States
| | - Pieter Tans
- ‡NOAA Earth System Research Laboratory, Boulder 80305, Colorado, United States
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22
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Utilization of Volatile Organic Compounds as an Alternative for Destructive Abatement. Catalysts 2015. [DOI: 10.3390/catal5031092] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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23
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Swarthout RF, Russo RS, Zhou Y, Miller BM, Mitchell B, Horsman E, Lipsky E, McCabe DC, Baum E, Sive BC. Impact of Marcellus Shale natural gas development in southwest Pennsylvania on volatile organic compound emissions and regional air quality. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:3175-84. [PMID: 25594231 DOI: 10.1021/es504315f] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The Marcellus Shale is the largest natural gas deposit in the U.S. and rapid development of this resource has raised concerns about regional air pollution. A field campaign was conducted in the southwestern Pennsylvania region of the Marcellus Shale to investigate the impact of unconventional natural gas (UNG) production operations on regional air quality. Whole air samples were collected throughout an 8050 km(2) grid surrounding Pittsburgh and analyzed for methane, carbon dioxide, and C1-C10 volatile organic compounds (VOCs). Elevated mixing ratios of methane and C2-C8 alkanes were observed in areas with the highest density of UNG wells. Source apportionment was used to identify characteristic emission ratios for UNG sources, and results indicated that UNG emissions were responsible for the majority of mixing ratios of C2-C8 alkanes, but accounted for a small proportion of alkene and aromatic compounds. The VOC emissions from UNG operations accounted for 17 ± 19% of the regional kinetic hydroxyl radical reactivity of nonbiogenic VOCs suggesting that natural gas emissions may affect compliance with federal ozone standards. A first approximation of methane emissions from the study area of 10.0 ± 5.2 kg s(-1) provides a baseline for determining the efficacy of regulatory emission control efforts.
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Affiliation(s)
- Robert F Swarthout
- Natural Resources and Earth System Science Program, University of New Hampshire , Durham, New Hampshire 03824, United States
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24
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Allen DT, Pacsi AP, Sullivan DW, Zavala-Araiza D, Harrison M, Keen K, Fraser MP, Daniel Hill A, Sawyer RF, Seinfeld JH. Methane emissions from process equipment at natural gas production sites in the United States: pneumatic controllers. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:633-40. [PMID: 25488196 DOI: 10.1021/es5040156] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Emissions from 377 gas actuated (pneumatic) controllers were measured at natural gas production sites and a small number of oil production sites, throughout the United States. A small subset of the devices (19%), with whole gas emission rates in excess of 6 standard cubic feet per hour (scf/h), accounted for 95% of emissions. More than half of the controllers recorded emissions of 0.001 scf/h or less during 15 min of measurement. Pneumatic controllers in level control applications on separators and in compressor applications had higher emission rates than controllers in other types of applications. Regional differences in emissions were observed, with the lowest emissions measured in the Rocky Mountains and the highest emissions in the Gulf Coast. Average methane emissions per controller reported in this work are 17% higher than the average emissions per controller in the 2012 EPA greenhouse gas national emission inventory (2012 GHG NEI, released in 2014); the average of 2.7 controllers per well observed in this work is higher than the 1.0 controllers per well reported in the 2012 GHG NEI.
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Affiliation(s)
- David T Allen
- Center for Energy and Environmental Resources, University of Texas at Austin , 10100 Burnet Road, Building 133, M.S. R7100, Austin, Texas 78758, United States
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25
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High winter ozone pollution from carbonyl photolysis in an oil and gas basin. Nature 2014; 514:351-4. [PMID: 25274311 DOI: 10.1038/nature13767] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 08/06/2014] [Indexed: 11/08/2022]
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26
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Allen DT. Methane emissions from natural gas production and use: reconciling bottom-up and top-down measurements. Curr Opin Chem Eng 2014. [DOI: 10.1016/j.coche.2014.05.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Yacovitch TI, Herndon SC, Roscioli JR, Floerchinger C, McGovern RM, Agnese M, Pétron G, Kofler J, Sweeney C, Karion A, Conley SA, Kort EA, Nähle L, Fischer M, Hildebrandt L, Koeth J, McManus JB, Nelson DD, Zahniser MS, Kolb CE. Demonstration of an ethane spectrometer for methane source identification. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:8028-34. [PMID: 24945706 DOI: 10.1021/es501475q] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Methane is an important greenhouse gas and tropospheric ozone precursor. Simultaneous observation of ethane with methane can help identify specific methane source types. Aerodyne Ethane-Mini spectrometers, employing recently available mid-infrared distributed feedback tunable diode lasers (DFB-TDL), provide 1 s ethane measurements with sub-ppb precision. In this work, an Ethane-Mini spectrometer has been integrated into two mobile sampling platforms, a ground vehicle and a small airplane, and used to measure ethane/methane enhancement ratios downwind of methane sources. Methane emissions with precisely known sources are shown to have ethane/methane enhancement ratios that differ greatly depending on the source type. Large differences between biogenic and thermogenic sources are observed. Variation within thermogenic sources are detected and tabulated. Methane emitters are classified by their expected ethane content. Categories include the following: biogenic (<0.2%), dry gas (1-6%), wet gas (>6%), pipeline grade natural gas (<15%), and processed natural gas liquids (>30%). Regional scale observations in the Dallas/Fort Worth area of Texas show two distinct ethane/methane enhancement ratios bridged by a transitional region. These results demonstrate the usefulness of continuous and fast ethane measurements in experimental studies of methane emissions, particularly in the oil and natural gas sector.
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Affiliation(s)
- Tara I Yacovitch
- Aerodyne Research Inc., Billerica, Massachusetts 01821, United States
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Sommariva R, Blake RS, Cuss RJ, Cordell RL, Harrington JF, White IR, Monks PS. Observations of the release of non-methane hydrocarbons from fractured shale. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:8891-8896. [PMID: 24978099 DOI: 10.1021/es502508w] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The organic content of shale has become of commercial interest as a source of hydrocarbons, owing to the development of hydraulic fracturing ("fracking"). While the main focus is on the extraction of methane, shale also contains significant amounts of non-methane hydrocarbons (NMHCs). We describe the first real-time observations of the release of NMHCs from a fractured shale. Samples from the Bowland-Hodder formation (England) were analyzed under different conditions using mass spectrometry, with the objective of understanding the dynamic process of gas release upon fracturing of the shale. A wide range of NMHCs (alkanes, cycloalkanes, aromatics, and bicyclic hydrocarbons) are released at parts per million or parts per billion level with temperature- and humidity-dependent release rates, which can be rationalized in terms of the physicochemical characteristics of different hydrocarbon classes. Our results indicate that higher energy inputs (i.e., temperatures) significantly increase the amount of NMHCs released from shale, while humidity tends to suppress it; additionally, a large fraction of the gas is released within the first hour after the shale has been fractured. These findings suggest that other hydrocarbons of commercial interest may be extracted from shale and open the possibility to optimize the "fracking" process, improving gas yields and reducing environmental impacts.
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Affiliation(s)
- Roberto Sommariva
- Department of Chemistry, University of Leicester , Leicester LE1 7RH, United Kingdom
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29
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Helmig D, Thompson CR, Evans J, Boylan P, Hueber J, Park JH. Highly elevated atmospheric levels of volatile organic compounds in the Uintah Basin, Utah. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:4707-15. [PMID: 24624890 DOI: 10.1021/es405046r] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Oil and natural gas production in the Western United States has grown rapidly in recent years, and with this industrial expansion, growing environmental concerns have arisen regarding impacts on water supplies and air quality. Recent studies have revealed highly enhanced atmospheric levels of volatile organic compounds (VOCs) from primary emissions in regions of heavy oil and gas development and associated rapid photochemical production of ozone during winter. Here, we present surface and vertical profile observations of VOC from the Uintah Basin Winter Ozone Studies conducted in January-February of 2012 and 2013. These measurements identify highly elevated levels of atmospheric alkane hydrocarbons with enhanced rates of C2-C5 nonmethane hydrocarbon (NMHC) mean mole fractions during temperature inversion events in 2013 at 200-300 times above the regional and seasonal background. Elevated atmospheric NMHC mole fractions coincided with build-up of ambient 1-h ozone to levels exceeding 150 ppbv (parts per billion by volume). The total annual mass flux of C2-C7 VOC was estimated at 194 ± 56 × 10(6) kg yr(-1), equivalent to the annual VOC emissions of a fleet of ∼100 million automobiles. Total annual fugitive emission of the aromatic compounds benzene and toluene, considered air toxics, were estimated at 1.6 ± 0.4 × 10(6) and 2.0 ± 0.5 × 10(6) kg yr(-1), respectively. These observations reveal a strong causal link between oil and gas emissions, accumulation of air toxics, and significant production of ozone in the atmospheric surface layer.
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Affiliation(s)
- D Helmig
- Institute of Arctic and Alpine Research (INSTAAR), University of Colorado , Boulder, Colorado 80309-0450, United States
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Field RA, Soltis J, Murphy S. Air quality concerns of unconventional oil and natural gas production. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2014; 16:954-969. [PMID: 24699994 DOI: 10.1039/c4em00081a] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Increased use of hydraulic fracturing ("fracking") in unconventional oil and natural gas (O & NG) development from coal, sandstone, and shale deposits in the United States (US) has created environmental concerns over water and air quality impacts. In this perspective we focus on how the production of unconventional O & NG affects air quality. We pay particular attention to shale gas as this type of development has transformed natural gas production in the US and is set to become important in the rest of the world. A variety of potential emission sources can be spread over tens of thousands of acres of a production area and this complicates assessment of local and regional air quality impacts. We outline upstream activities including drilling, completion and production. After contrasting the context for development activities in the US and Europe we explore the use of inventories for determining air emissions. Location and scale of analysis is important, as O & NG production emissions in some US basins account for nearly 100% of the pollution burden, whereas in other basins these activities make up less than 10% of total air emissions. While emission inventories are beneficial to quantifying air emissions from a particular source category, they do have limitations when determining air quality impacts from a large area. Air monitoring is essential, not only to validate inventories, but also to measure impacts. We describe the use of measurements, including ground-based mobile monitoring, network stations, airborne, and satellite platforms for measuring air quality impacts. We identify nitrogen oxides, volatile organic compounds (VOC), ozone, hazardous air pollutants (HAP), and methane as pollutants of concern related to O & NG activities. These pollutants can contribute to air quality concerns and they may be regulated in ambient air, due to human health or climate forcing concerns. Close to well pads, emissions are concentrated and exposure to a wide range of pollutants is possible. Public health protection is improved when emissions are controlled and facilities are located away from where people live. Based on lessons learned in the US we outline an approach for future unconventional O & NG development that includes regulation, assessment and monitoring.
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Affiliation(s)
- R A Field
- Department of Atmospheric Science, University of Wyoming, Laramie, WY 82071, USA.
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31
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Caulton DR, Shepson PB, Santoro RL, Sparks JP, Howarth RW, Ingraffea AR, Cambaliza MOL, Sweeney C, Karion A, Davis KJ, Stirm BH, Montzka SA, Miller BR. Toward a better understanding and quantification of methane emissions from shale gas development. Proc Natl Acad Sci U S A 2014; 111:6237-42. [PMID: 24733927 PMCID: PMC4035982 DOI: 10.1073/pnas.1316546111] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The identification and quantification of methane emissions from natural gas production has become increasingly important owing to the increase in the natural gas component of the energy sector. An instrumented aircraft platform was used to identify large sources of methane and quantify emission rates in southwestern PA in June 2012. A large regional flux, 2.0-14 g CH4 s(-1) km(-2), was quantified for a ∼ 2,800-km(2) area, which did not differ statistically from a bottom-up inventory, 2.3-4.6 g CH4 s(-1) km(-2). Large emissions averaging 34 g CH4/s per well were observed from seven well pads determined to be in the drilling phase, 2 to 3 orders of magnitude greater than US Environmental Protection Agency estimates for this operational phase. The emissions from these well pads, representing ∼ 1% of the total number of wells, account for 4-30% of the observed regional flux. More work is needed to determine all of the sources of methane emissions from natural gas production, to ascertain why these emissions occur and to evaluate their climate and atmospheric chemistry impacts.
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Affiliation(s)
| | - Paul B. Shepson
- Departments of Chemistry
- Earth, Atmospheric and Planetary Science, and
| | - Renee L. Santoro
- Physicians, Scientists and Engineers for Healthy Energy, Ithaca, NY 14851
| | | | | | - Anthony R. Ingraffea
- Physicians, Scientists and Engineers for Healthy Energy, Ithaca, NY 14851
- Civil and Environmental Engineering, Cornell University, Ithaca, NY 14853
| | | | - Colm Sweeney
- National Oceanic and Atmospheric Administration, Boulder, CO 80305
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309; and
| | - Anna Karion
- National Oceanic and Atmospheric Administration, Boulder, CO 80305
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309; and
| | - Kenneth J. Davis
- Department of Meteorology, The Pennsylvania State University, University Park, PA 16802
| | - Brian H. Stirm
- Aviation Technology, Purdue University, West Lafayette, IN 47907
| | | | - Ben R. Miller
- National Oceanic and Atmospheric Administration, Boulder, CO 80305
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309; and
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Moore CW, Zielinska B, Pétron G, Jackson RB. Air impacts of increased natural gas acquisition, processing, and use: a critical review. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:8349-8359. [PMID: 24588259 DOI: 10.1021/es4053472] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
During the past decade, technological advancements in the United States and Canada have led to rapid and intensive development of many unconventional natural gas plays (e.g., shale gas, tight sand gas, coal-bed methane), raising concerns about environmental impacts. Here, we summarize the current understanding of local and regional air quality impacts of natural gas extraction, production, and use. Air emissions from the natural gas life cycle include greenhouse gases, ozone precursors (volatile organic compounds and nitrogen oxides), air toxics, and particulates. National and state regulators primarily use generic emission inventories to assess the climate, air quality, and health impacts of natural gas systems. These inventories rely on limited, incomplete, and sometimes outdated emission factors and activity data, based on few measurements. We discuss case studies for specific air impacts grouped by natural gas life cycle segment, summarize the potential benefits of using natural gas over other fossil fuels, and examine national and state emission regulations pertaining to natural gas systems. Finally, we highlight specific gaps in scientific knowledge and suggest that substantial additional measurements of air emissions from the natural gas life cycle are essential to understanding the impacts and benefits of this resource.
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Affiliation(s)
- Christopher W Moore
- Desert Research Institute , Division of Atmospheric Sciences, Reno, Nevada 89512, United States
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33
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Brandt AR, Heath GA, Kort EA, O'Sullivan F, Pétron G, Jordaan SM, Tans P, Wilcox J, Gopstein AM, Arent D, Wofsy S, Brown NJ, Bradley R, Stucky GD, Eardley D, Harriss R. Methane Leaks from North American Natural Gas Systems. Science 2014; 343:733-5. [PMID: 24531957 DOI: 10.1126/science.1247045] [Citation(s) in RCA: 234] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Rich A, Grover JP, Sattler ML. An exploratory study of air emissions associated with shale gas development and production in the Barnett Shale. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2014; 64:61-72. [PMID: 24620403 DOI: 10.1080/10962247.2013.832713] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
UNLABELLED Information regarding air emissions from shale gas extraction and production is critically important given production is occurring in highly urbanized areas across the United States. Objectives of this exploratory study were to collect ambient air samples in residential areas within 61 m (200 feet) of shale gas extraction/production and determine whether a "fingerprint" of chemicals can be associated with shale gas activity. Statistical analyses correlating fingerprint chemicals with methane, equipment, and processes of extraction/production were performed. Ambient air sampling in residential areas of shale gas extraction and production was conducted at six counties in the Dallas/Fort Worth (DFW) Metroplex from 2008 to 2010. The 39 locations tested were identified by clients that requested monitoring. Seven sites were sampled on 2 days (typically months later in another season), and two sites were sampled on 3 days, resulting in 50 sets of monitoring data. Twenty-four-hour passive samples were collected using summa canisters. Gas chromatography/mass spectrometer analysis was used to identify organic compounds present. Methane was present in concentrations above laboratory detection limits in 49 out of 50 sampling data sets. Most of the areas investigated had atmospheric methane concentrations considerably higher than reported urban background concentrations (1.8-2.0 ppm(v)). Other chemical constituents were found to be correlated with presence of methane. A principal components analysis (PCA) identified multivariate patterns of concentrations that potentially constitute signatures of emissions from different phases of operation at natural gas sites. The first factor identified through the PCA proved most informative. Extreme negative values were strongly and statistically associated with the presence of compressors at sample sites. The seven chemicals strongly associated with this factor (o-xylene, ethylbenzene, 1,2,4-trimethylbenzene, m- and p-xylene, 1,3,5-trimethylbenzene, toluene, and benzene) thus constitute a potential fingerprint of emissions associated with compression. IMPLICATIONS Information regarding air emissions from shale gas development and production is critically important given production is now occurring in highly urbanized areas across the United States. Methane, the primary shale gas constituent, contributes substantially to climate change; other natural gas constituents are known to have adverse health effects. This study goes beyond previous Barnett Shale field studies by encompassing a wider variety of production equipment (wells, tanks, compressors, and separators) and a wider geographical region. The principal components analysis, unique to this study, provides valuable information regarding the ability to anticipate associated shale gas chemical constituents.
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35
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Adgate JL, Goldstein BD, McKenzie LM. Potential public health hazards, exposures and health effects from unconventional natural gas development. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:8307-20. [PMID: 24564405 DOI: 10.1021/es404621d] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The rapid increase in unconventional natural gas (UNG) development in the United States during the past decade has brought wells and related infrastructure closer to population centers. This review evaluates risks to public health from chemical and nonchemical stressors associated with UNG, describes likely exposure pathways and potential health effects, and identifies major uncertainties to address with future research. The most important occupational stressors include mortality, exposure to hazardous materials and increased risk of industrial accidents. For communities near development and production sites the major stressors are air pollutants, ground and surface water contamination, truck traffic and noise pollution, accidents and malfunctions, and psychosocial stress associated with community change. Despite broad public concern, no comprehensive population-based studies of the public health effects of UNG operations exist. Major uncertainties are the unknown frequency and duration of human exposure, future extent of development, potential emission control and mitigation strategies, and a paucity of baseline data to enable substantive before and after comparisons for affected populations and environmental media. Overall, the current literature suggests that research needs to address these uncertainties before we can reasonably quantify the likelihood of occurrence or magnitude of adverse health effects associated with UNG production in workers and communities.
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Affiliation(s)
- John L Adgate
- Colorado School of Public Health, University of Colorado Denver , 13001 E. 17th Place, Campus Box B119, Aurora, Colorado 80045, United States
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36
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Roy AA, Adams PJ, Robinson AL. Air pollutant emissions from the development, production, and processing of Marcellus Shale natural gas. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2014; 64:19-37. [PMID: 24620400 DOI: 10.1080/10962247.2013.826151] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
UNLABELLED The Marcellus Shale is one of the largest natural gas reserves in the United States; it has recently been the focus of intense drilling and leasing activity. This paper describes an air emissions inventory for the development, production, and processing of natural gas in the Marcellus Shale region for 2009 and 2020. It includes estimates of the emissions of oxides of nitrogen (NOx), volatile organic compounds (VOCs), and primary fine particulate matter (< or = 2.5 microm aerodynamic diameter; PM2.5) from major activities such as drilling, hydraulic fracturing, compressor stations, and completion venting. The inventory is constructed using a process-level approach; a Monte Carlo analysis is used to explicitly account for the uncertainty. Emissions were estimated for 2009 and projected to 2020, accounting for the effects of existing and potential additional regulations. In 2020, Marcellus activities are predicted to contribute 6-18% (95% confidence interval) of the NOx emissions in the Marcellus region, with an average contribution of 12% (129 tons/day). In 2020, the predicted contribution of Marcellus activities to the regional anthropogenic VOC emissions ranged between 7% and 28% (95% confidence interval), with an average contribution of 12% (100 tons/day). These estimates account for the implementation of recently promulgated regulations such as the Tier 4 off-road diesel engine regulation and the US. Environmental Protection Agency's (EPA) Oil and Gas Rule. These regulations significantly reduce the Marcellus VOC and NOx emissions, but there are significant opportunities for further reduction in these emissions using existing technologies. IMPLICATIONS The Marcellus Shale is one of the largest natural gas reserves in United States. The development and production of this gas may emit substantial amounts of oxides of nitrogen and volatile organic compounds. These emissions may have special significance because Marcellus development is occurring close to areas that have been designated nonattainment for the ozone standard. Control technologies exist to substantially reduce these impacts. PM2.5 emissions are predicted to be negligible in a regional context, but elemental carbon emissions from diesel powered equipment may be important.
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Abstract
This study quantitatively estimates the spatial distribution of anthropogenic methane sources in the United States by combining comprehensive atmospheric methane observations, extensive spatial datasets, and a high-resolution atmospheric transport model. Results show that current inventories from the US Environmental Protection Agency (EPA) and the Emissions Database for Global Atmospheric Research underestimate methane emissions nationally by a factor of ∼1.5 and ∼1.7, respectively. Our study indicates that emissions due to ruminants and manure are up to twice the magnitude of existing inventories. In addition, the discrepancy in methane source estimates is particularly pronounced in the south-central United States, where we find total emissions are ∼2.7 times greater than in most inventories and account for 24 ± 3% of national emissions. The spatial patterns of our emission fluxes and observed methane-propane correlations indicate that fossil fuel extraction and refining are major contributors (45 ± 13%) in the south-central United States. This result suggests that regional methane emissions due to fossil fuel extraction and processing could be 4.9 ± 2.6 times larger than in EDGAR, the most comprehensive global methane inventory. These results cast doubt on the US EPA's recent decision to downscale its estimate of national natural gas emissions by 25-30%. Overall, we conclude that methane emissions associated with both the animal husbandry and fossil fuel industries have larger greenhouse gas impacts than indicated by existing inventories.
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38
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Gilman JB, Lerner BM, Kuster WC, de Gouw JA. Source signature of volatile organic compounds from oil and natural gas operations in northeastern Colorado. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:1297-1305. [PMID: 23316938 DOI: 10.1021/es304119a] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
An extensive set of volatile organic compounds (VOCs) was measured at the Boulder Atmospheric Observatory (BAO) in winter 2011 in order to investigate the composition and influence of VOC emissions from oil and natural gas (O&NG) operations in northeastern Colorado. BAO is 30 km north of Denver and is in the southwestern section of Wattenberg Field, one of Colorado's most productive O&NG fields. We compare VOC concentrations at BAO to those of other U.S. cities and summertime measurements at two additional sites in northeastern Colorado, as well as the composition of raw natural gas from Wattenberg Field. These comparisons show that (i) the VOC source signature associated with O&NG operations can be clearly differentiated from urban sources dominated by vehicular exhaust, and (ii) VOCs emitted from O&NG operations are evident at all three measurement sites in northeastern Colorado. At BAO, the reactivity of VOCs with the hydroxyl radical (OH) was dominated by C(2)-C(6) alkanes due to their remarkably large abundances (e.g., mean propane = 27.2 ppbv). Through statistical regression analysis, we estimate that on average 55 ± 18% of the VOC-OH reactivity was attributable to emissions from O&NG operations indicating that these emissions are a significant source of ozone precursors.
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Affiliation(s)
- J B Gilman
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado, United States.
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39
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Long-term decline of global atmospheric ethane concentrations and implications for methane. Nature 2012; 488:490-4. [DOI: 10.1038/nature11342] [Citation(s) in RCA: 138] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Accepted: 06/19/2012] [Indexed: 11/09/2022]
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40
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Pétron G, Frost G, Miller BR, Hirsch AI, Montzka SA, Karion A, Trainer M, Sweeney C, Andrews AE, Miller L, Kofler J, Bar-Ilan A, Dlugokencky EJ, Patrick L, Moore CT, Ryerson TB, Siso C, Kolodzey W, Lang PM, Conway T, Novelli P, Masarie K, Hall B, Guenther D, Kitzis D, Miller J, Welsh D, Wolfe D, Neff W, Tans P. Hydrocarbon emissions characterization in the Colorado Front Range: A pilot study. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011jd016360] [Citation(s) in RCA: 323] [Impact Index Per Article: 26.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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41
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Sather ME, Cavender K. Update of long-term trends analysis of ambient 8-hour ozone and precursor monitoring data in the South Central U.S.; encouraging news. ACTA ACUST UNITED AC 2012; 14:666-76. [PMID: 22222255 DOI: 10.1039/c2em10862c] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In the South Central U.S., lower tropospheric ozone pollution continues to be a challenging problem. This paper provides an update on long-term trends analyses of the ambient ozone and precursor monitoring data collected over the past 25 years (1986-2010) in four South Central U.S. cities, following up on a previous published review of 20 year trends (M.E. Sather and K. Cavender, J. Environ. Monit., 2007, 9, 143-150). The results of these analyses should be useful to air quality scientists, managers, planners, and modelers in assessing the effectiveness of nitrogen oxides (NO(x)) and volatile organic compounds (VOC) pollution controls for ambient ozone concentration reduction programs. Large amounts of quantitative information for each South Central U.S. city are concisely synthesized into one graphic per city. Results reported in this paper show significant long-term decreases in ambient ozone and precursor concentrations in all four South Central U.S. cities, especially over the recent five-year period 2006-2010.
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Affiliation(s)
- Mark E Sather
- Air Quality Analysis Section, U.S. EPA Region 6, 1445 Ross Avenue, Dallas, TX 75202, USA
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42
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Ali N, Sorkhoh N, Salamah S, Eliyas M, Radwan S. The potential of epiphytic hydrocarbon-utilizing bacteria on legume leaves for attenuation of atmospheric hydrocarbon pollutants. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2012; 93:113-20. [PMID: 22054577 DOI: 10.1016/j.jenvman.2011.08.014] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Revised: 08/16/2011] [Accepted: 08/17/2011] [Indexed: 05/31/2023]
Abstract
The leaves of two legumes, peas and beans, harbored on their surfaces up to 9×10⁷ cells g⁻¹ of oil-utilizing bacteria. Less numbers, up to 5×10⁵ cells g⁻¹ inhabited leaves of two nonlegume crops, namely tomato and sunflower. Older leaves accommodated more of such bacteria than younger ones. Plants raised in oily environments were colonized by much more oil-utilizing bacteria than those raised in pristine (oil-free) environments. Similar numbers were counted on the same media in which nitrogen salt was deleted, indicating that most phyllospheric bacteria were probably diazotrophic. Most dominant were Microbacterium spp. followed by Rhodococcus spp., Citrobacter freundii, in addition to several other minor species. The pure bacterial isolates could utilize leaf tissue hydrocarbons, and consume considerable proportions of crude oil, phenanthrene (an aromatic hydrocarbon) and n-octadecane (an alkane) in batch cultures. Bacterial consortia on fresh (but not on previously autoclaved) leaves of peas and beans could also consume substantial proportions of the surrounding volatile oil hydrocarbons in closed microcosms. It was concluded that phytoremediation through phyllosphere technology could be useful in remediating atmospheric hydrocarbon pollutants.
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Affiliation(s)
- Nida Ali
- Department of Biological Sciences, Kuwait University, Safat 13060, Kuwait
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43
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Brown SS, Dubé WP, Peischl J, Ryerson TB, Atlas E, Warneke C, de Gouw JA, te Lintel Hekkert S, Brock CA, Flocke F, Trainer M, Parrish DD, Feshenfeld FC, Ravishankara AR. Budgets for nocturnal VOC oxidation by nitrate radicals aloft during the 2006 Texas Air Quality Study. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2011jd016544] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Steven S. Brown
- Chemical Sciences Division, Earth System Research Laboratory; NOAA; Boulder Colorado USA
| | - William P. Dubé
- Chemical Sciences Division, Earth System Research Laboratory; NOAA; Boulder Colorado USA
- Cooperative Institute for Research in Environmental Sciences; University of Colorado at Boulder; Boulder Colorado USA
| | - Jeff Peischl
- Chemical Sciences Division, Earth System Research Laboratory; NOAA; Boulder Colorado USA
- Cooperative Institute for Research in Environmental Sciences; University of Colorado at Boulder; Boulder Colorado USA
| | - Thomas B. Ryerson
- Chemical Sciences Division, Earth System Research Laboratory; NOAA; Boulder Colorado USA
| | - Elliot Atlas
- Marine and Atmospheric Chemistry, Rosenstiel School of Marine and Atmospheric Science; University of Miami; Miami Florida USA
| | - Carsten Warneke
- Chemical Sciences Division, Earth System Research Laboratory; NOAA; Boulder Colorado USA
- Cooperative Institute for Research in Environmental Sciences; University of Colorado at Boulder; Boulder Colorado USA
| | - Joost A. de Gouw
- Chemical Sciences Division, Earth System Research Laboratory; NOAA; Boulder Colorado USA
- Cooperative Institute for Research in Environmental Sciences; University of Colorado at Boulder; Boulder Colorado USA
| | | | - Charles A. Brock
- Chemical Sciences Division, Earth System Research Laboratory; NOAA; Boulder Colorado USA
| | - Frank Flocke
- National Center for Atmospheric Research; Boulder Colorado USA
| | - Michael Trainer
- Chemical Sciences Division, Earth System Research Laboratory; NOAA; Boulder Colorado USA
| | - David D. Parrish
- Chemical Sciences Division, Earth System Research Laboratory; NOAA; Boulder Colorado USA
| | - Frederick C. Feshenfeld
- Chemical Sciences Division, Earth System Research Laboratory; NOAA; Boulder Colorado USA
- Cooperative Institute for Research in Environmental Sciences; University of Colorado at Boulder; Boulder Colorado USA
| | - A. R. Ravishankara
- Chemical Sciences Division, Earth System Research Laboratory; NOAA; Boulder Colorado USA
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Vay SA, Choi Y, Vadrevu KP, Blake DR, Tyler SC, Wisthaler A, Hecobian A, Kondo Y, Diskin GS, Sachse GW, Woo JH, Weinheimer AJ, Burkhart JF, Stohl A, Wennberg PO. Patterns of CO2and radiocarbon across high northern latitudes during International Polar Year 2008. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2011jd015643] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Minh TDC, Oliver SR, Ngo J, Flores R, Midyett J, Meinardi S, Carlson MK, Rowland FS, Blake DR, Galassetti PR. Noninvasive measurement of plasma glucose from exhaled breath in healthy and type 1 diabetic subjects. Am J Physiol Endocrinol Metab 2011; 300:E1166-75. [PMID: 21467303 PMCID: PMC3118590 DOI: 10.1152/ajpendo.00634.2010] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Effective management of diabetes mellitus, affecting tens of millions of patients, requires frequent assessment of plasma glucose. Patient compliance for sufficient testing is often reduced by the unpleasantness of current methodologies, which require blood samples and often cause pain and skin callusing. We propose that the analysis of volatile organic compounds (VOCs) in exhaled breath can be used as a novel, alternative, noninvasive means to monitor glycemia in these patients. Seventeen healthy (9 females and 8 males, 28.0 ± 1.0 yr) and eight type 1 diabetic (T1DM) volunteers (5 females and 3 males, 25.8 ± 1.7 yr) were enrolled in a 240-min triphasic intravenous dextrose infusion protocol (baseline, hyperglycemia, euglycemia-hyperinsulinemia). In T1DM patients, insulin was also administered (using differing protocols on 2 repeated visits to separate the effects of insulinemia on breath composition). Exhaled breath and room air samples were collected at 12 time points, and concentrations of ~100 VOCs were determined by gas chromatography and matched with direct plasma glucose measurements. Standard least squares regression was used on several subsets of exhaled gases to generate multilinear models to predict plasma glucose for each subject. Plasma glucose estimates based on two groups of four gases each (cluster A: acetone, methyl nitrate, ethanol, and ethyl benzene; cluster B: 2-pentyl nitrate, propane, methanol, and acetone) displayed very strong correlations with glucose concentrations (0.883 and 0.869 for clusters A and B, respectively) across nearly 300 measurements. Our study demonstrates the feasibility to accurately predict glycemia through exhaled breath analysis over a broad range of clinically relevant concentrations in both healthy and T1DM subjects.
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Affiliation(s)
- Timothy D C Minh
- Department of Pharmacology, University of California Irvine, Irvine, CA 92697, USA.
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Xiao Y, Logan JA, Jacob DJ, Hudman RC, Yantosca R, Blake DR. Global budget of ethane and regional constraints on U.S. sources. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jd009415] [Citation(s) in RCA: 147] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Aydin M, Williams MB, Saltzman ES. Feasibility of reconstructing paleoatmospheric records of selected alkanes, methyl halides, and sulfur gases from Greenland ice cores. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006jd008027] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Parrish DD, Dunlea EJ, Atlas EL, Schauffler S, Donnelly S, Stroud V, Goldstein AH, Millet DB, McKay M, Jaffe DA, Price HU, Hess PG, Flocke F, Roberts JM. Changes in the photochemical environment of the temperate North Pacific troposphere in response to increased Asian emissions. ACTA ACUST UNITED AC 2004. [DOI: 10.1029/2004jd004978] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- D. D. Parrish
- Aeronomy Laboratory; National Oceanic and Atmospheric Administration; Boulder Colorado USA
| | - E. J. Dunlea
- Aeronomy Laboratory; National Oceanic and Atmospheric Administration; Boulder Colorado USA
| | - E. L. Atlas
- Atmospheric Chemistry Division; National Center for Atmospheric Research; Boulder Colorado USA
| | - S. Schauffler
- Atmospheric Chemistry Division; National Center for Atmospheric Research; Boulder Colorado USA
| | - S. Donnelly
- Atmospheric Chemistry Division; National Center for Atmospheric Research; Boulder Colorado USA
| | - V. Stroud
- Atmospheric Chemistry Division; National Center for Atmospheric Research; Boulder Colorado USA
| | - A. H. Goldstein
- Department of Environmental Science, Policy, and Management; University of California; Berkeley California USA
| | - D. B. Millet
- Department of Environmental Science, Policy, and Management; University of California; Berkeley California USA
| | - M. McKay
- Department of Environmental Science, Policy, and Management; University of California; Berkeley California USA
| | - D. A. Jaffe
- Interdisciplinary Arts and Sciences; University of Washington-Bothell; Bothell Washington USA
| | - H. U. Price
- Interdisciplinary Arts and Sciences; University of Washington-Bothell; Bothell Washington USA
- Department of Chemistry; University of Washington; Seattle Washington USA
| | - P. G. Hess
- Atmospheric Chemistry Division; National Center for Atmospheric Research; Boulder Colorado USA
| | - F. Flocke
- Atmospheric Chemistry Division; National Center for Atmospheric Research; Boulder Colorado USA
| | - J. M. Roberts
- Aeronomy Laboratory; National Oceanic and Atmospheric Administration; Boulder Colorado USA
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