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Exposure to vehicle emissions results in altered blood brain barrier permeability and expression of matrix metalloproteinases and tight junction proteins in mice

Description: Article on the exposure to vehicle emissions results in altered blood brain barrier permeability and expression of matrix metalloproteinases and tight junction proteins in mice.
Date: June 18, 2013
Creator: Oppenheim, Hannah A.; Lucero, JoAnn; Guyot, Anne-Cécile; Herbert, Lindsay M.; McDonald, Jacob D.; Mabondzo, Aloïse et al.
Partner: UNT College of Arts and Sciences

Ozone Pollution of Shale Gas Activities in North Texas

Description: The effect of shale gas activities on ground-level ozone pollution in the Dallas-Fort Worth area is studied in detail here. Ozone is a highly reactive species with harmful effects on human and environment. Shale gas development, or fracking, involves activities such as hydraulic fracturing, drilling, fluid mixing, and trucks idling that are sources of nitrogen oxides (NOX) and volatile organic compounds (VOC), two of the most important precursors of ozone. In this study two independent approaches have been applied in evaluating the influences on ozone concentrations. In the first approach, the influence of meteorology were removed from ozone time series through the application of Kolmogorov-Zurbenko low-pass filter, logarithmic transformation, and subsequent multi-linear regression. Ozone measurement data were acquired from Texas Commission on Environmental Quality (TCEQ) monitoring stations for 14 years. The comparison between ozone trends in non-shale gas region and shale gas region shows increasing ozone trends at the monitoring stations in close proximity to the Barnett Shale activities. In the second approach, the CAMx photochemical model was used to assess the sensitivity of ozone to the NOX and VOC sources associated with shale oil and gas activities. Brute force method was applied on Barnett Shale and Haynesville Shale emission sources to generate four hypothetical scenarios. Ozone sensitivity analysis was performed for a future year of 2018 and it was based on the photochemical simulation that TCEQ had developed for demonstrating ozone attainment under the State Implementation Plan (SIP). Results showed various level of ozone impact at different locations within the DFW region attributed to area and point sources of emissions in the shale region. Maximum ozone impact due to shale gas activities is expected to be in the order of several parts per billion, while lower impacts on design values were predicted. The results from the photochemical modeling can ...
Date: May 2016
Creator: Ahmadi, Mahdi
Partner: UNT Libraries

Clean Air Status and Trends Network Annual Report: 2004

Description: Annual report of the Clean Air Status and Trends Network (CASTNET) describing the program and data collection. It also presents information on air quality and recorded concentrations of pollutants such as ozone, sulfur, gases, and other elements of concern.
Date: November 2005
Creator: MACTEC Engineering and Consulting, Inc.
Partner: UNT Libraries Government Documents Department

Clean Air Status and Trends Network Annual Report: 2011

Description: Annual report of the Clean Air Status and Trends Network (CASTNET) describing the program and data collection. It also presents information on air quality and recorded concentrations of pollutants such as ozone, sulfur, gases, and other elements of concern.
Date: February 2013
Creator: AMEC Environement & Infrastucture, Inc.
Partner: UNT Libraries Government Documents Department

Clean Air Status and Trends Network Annual Report: 2012

Description: Annual report of the Clean Air Status and Trends Network (CASTNET) describing the program and data collection. It also presents information on air quality and recorded concentrations of pollutants such as ozone, sulfur, gases, and other elements of concern.
Date: April 2014
Creator: AMEC Environment & Infrastructure, Inc.
Partner: UNT Libraries Government Documents Department

Clean Air Status and Trends Network Annual Report: 2014

Description: Annual report of the Clean Air Status and Trends Network (CASTNET) describing the program and data collection. It also presents information on air quality and recorded concentrations of pollutants such as ozone, sulfur, gases, and other elements of concern.
Date: December 2016
Creator: Amec Foster Wheeler Environment & Infrastructure, Inc.
Partner: UNT Libraries Government Documents Department

Clean Air Status and Trends Network Annual Report: 2008

Description: Annual report of the Clean Air Status and Trends Network (CASTNET) describing the program and data collection. It also presents information on air quality and recorded concentrations of pollutants such as ozone, sulfur, gases, and other elements of concern.
Date: February 2010
Creator: MACTEC Engineering and Consulting, Inc.
Partner: UNT Libraries Government Documents Department

Clean Air Status and Trends Network Annual Report: 2010

Description: Annual report of the Clean Air Status and Trends Network (CASTNET) describing the program and data collection. It also presents information on air quality and recorded concentrations of pollutants such as ozone, sulfur, gases, and other elements of concern.
Date: April 2012
Creator: AMEC Environment & Infrastructure, Inc.
Partner: UNT Libraries Government Documents Department

Clean Air Status and Trends Network Annual Report: 2009

Description: Annual report of the Clean Air Status and Trends Network (CASTNET) describing the program and data collection. It also presents information on air quality and recorded concentrations of pollutants such as ozone, sulfur, gases, and other elements of concern.
Date: February 2011
Creator: MACTEC Engineering and Consulting, Inc.
Partner: UNT Libraries Government Documents Department

Clean Air Status and Trends Network Annual Report: 2007

Description: Annual report of the Clean Air Status and Trends Network (CASTNET) describing the program and data collection. It also presents information on air quality and recorded concentrations of pollutants such as ozone, sulfur, gases, and other elements of concern.
Date: December 2008
Creator: MACTEC Engineering and Consulting, Inc.
Partner: UNT Libraries Government Documents Department

Clean Air Status and Trends Network Annual Report: 2005

Description: Annual report of the Clean Air Status and Trends Network (CASTNET) describing the program and data collection. It also presents information on air quality and recorded concentrations of pollutants such as ozone, sulfur, gases, and other elements of concern.
Date: December 2006
Creator: MACTEC Engineering and Consulting, Inc.
Partner: UNT Libraries Government Documents Department

Year 2005 Gulfwide Emission Inventory Study

Description: An inventory study for the air pollution emissions from the Outer Continental Shelf (OCS) oil and gas production-related sources in the Gulf of Mexico in the year 2005.
Date: December 2007
Creator: Wilson, Darcy; Billings, Richard; Oommen, Regi & Chang, Roger
Partner: UNT Libraries Government Documents Department

Year 2011 Gulfwide Emission Inventory Study

Description: A report assessing the potential impacts of air pollutant emissions from offshore oil and gas exploration, development, and production sources on the Outer Continental Shelf for the year 2011.
Date: November 2014
Creator: Wilson, D.; Billings, R.; Chang, R.; Perez, H. & Sellers, J.
Partner: UNT Libraries Government Documents Department

Air Pollution: Implementation of the Clean Air Act Amendments of 1990

Description: Testimony issued by the General Accounting Office with an abstract that begins "GAO discussed the Environmental Protection Agency's (EPA) implementation of the Clean Air Act Amendments and on sources regulated by multiple provisions of the act, focusing on: (1) the status of EPA's implementation of requirements established by the 1990 amendments; (2) the views from the stakeholders--state governments, local programs, industries that are regulated under the act, and environmental advocacy groups--on the issues that either helped or hindered the implementation of the 1990 amendments; (3) examples of emission sources subject to regulation under more than one Clean Air Act program; and (4) the status of EPA's efforts to facilitate compliance for such sources."
Date: May 17, 2000
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Air Pollution: Meeting Future Electricity Demand Will Increase Emission of Some Harmful Substances

Description: A letter report issued by the General Accounting Office with an abstract that begins "Electric power plants burn fuels that can produce harmful emissions, such as carbon dioxide, mercury, nitrogen oxides, and sulfur dioxide, which can pose human health and environmental risks. To assess the potential risks of meeting future electricity demand, congressional committees asked GAO to (1) report on the Energy Information Administration's (EIA's) national and regional projections of such emissions by 2020, and (2) determine how the projections would change using alternative assumptions about future economic growth and other factors that advisers in these fields recommended. GAO also assessed the potential effects of future electricity demand on water demand and supply."
Date: October 30, 2002
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Air Pollution: Emissions from Older Electricity Generating Units

Description: A letter report issued by the General Accounting Office with an abstract that begins "Although fossil fuels--coal, natural gas, and oil--account for more than two thirds of the nation's electricity, generating units that burn these fuels are major sources of airborne emissions that pose health and environmental risks. To limit emissions and protect air quality, the Environmental Protection Agency regulates emissions of sulfur dioxide and nitrogen oxides from a variety of sources including electricity generating units that burn fossil fuels, other industrial sources, and automobiles. Older electricity generating units--those that began operating before 1972--emit 59 percent of the sulfur dioxide, 47 percent of the nitrogen oxides, and 42 percent of all electricity produced by fossil-fuel units. Units that began operating in or after 1972 are responsible for the remainder of the emissions and electricity production. For equal quantities of electricity generated, older units, in the aggregate, emitted twice as much sulfur dioxide and 25 percent more nitrogen oxides than newer units which must meet the new source standards for these substances. Older and newer units emitted about the same amount of carbon dioxide for equal quantities of electricity generated. Of the older units, those in the Mid-Atlantic, Midwest, and Southeast produced the majority of the emissions, and in disproportionate quantities for the amount of electricity they generated compared with units located in other parts of the country. Older units that burned coal released a disproportionate share of emissions for the electricity they produced compared with units burning natural gas and oil. Thirty-six percent of older units, in 2000, emitted sulfur dioxide at levels above the new source standards applicable to newer units, and 73 percent emitted nitrogen oxides at levels above the standards. These "additional" emissions--those above the standards for newer units--accounted for 34 percent of the sulfur dioxide and ...
Date: June 12, 2002
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Air Pollution: EPA's Actions to Resolve Concerns with the Fine Particulate Monitoring Program

Description: A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed the National Academy of Sciences March 1998 report on the Environmental Protection Agency's (EPA) plans to monitor particulate matter smaller than 2.5 microns (PM2.5), focusing on: (1) EPA's actions in response to the Academy's concerns with the planned PM2.5 monitoring program; and (2) the challenges that state and local agencies face in establishing and operating the PM2.5 monitoring program, as well as EPA's response to these challenges."
Date: August 12, 1999
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Air Pollution: EPA Should Improve Oversight of Emissions Reporting by Large Facilities

Description: A letter report issued by the General Accounting Office with an abstract that begins "The Environmental Protection Agency (EPA) performs limited oversight of states' processes for verifying the accuracy of large industrial facilities' emissions reports. EPA's data show that most emissions determinations from large sources are based on generic emissions factors. Although EPA allows facilities to estimate their emissions in this manner, EPA officials generally consider direct methods to be more reliable. The accuracy of these reports is important because they influence (1) the financing of states' regulatory programs through fees and (2) the development of emissions inventories, which, in turn, help regulators to develop control strategies and establish permit limits. Furthermore, steps taken to assess the accuracy of these reports, such as more thoroughly reviewing the supporting information, could improve compliance with Clean Air Act requirements. For example, a more thorough review of the information underlying a facility's emission reports, or a more systematic comparison of these reports over time, could identify increased emissions. Such indications could, in turn, trigger a review of compliance with new source review requirements, an area in which EPA found widespread noncompliance in four industries. In the four states that GAO reviewed, the states that had done the most detailed reviews found widespread inaccuracies. Although it is taking steps to improve its overall compliance monitoring strategy, EPA does not plan to evaluate states' processes for verifying emissions reports from large facilities."
Date: April 6, 2001
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Air Pollution: Air Quality and Respiratory Problems in and Near the Great Smoky Mountains

Description: Testimony issued by the General Accounting Office with an abstract that begins "Concerns have been growing about the air quality, visibility, and respiratory illnesses around the Great Smoky Mountains National Park, which straddles the border between North Carolina and Tennessee. This testimony analyzes recent trends in and contributing factors to (1) visibility impairments, (2) ground-level ozone, and (3) respiratory illnesses. This testimony also examines the Tennessee Valley Authority's (TVA) plans to reduce its emission of regulated pollutants. Visibility impairments and ozone are largely attributable to the following three types of emissions: sulfur dioxide, nitrogen oxides, and volatile organic compounds. The counties that border the park generally have slightly higher mortality rates from two types of respiratory illness. The three types of emissions interact in the atmosphere to form ozone gas and sulfate particles, which are linked to respiratory illnesses. In response to federal laws and other factors, TVA is making substantial environment-related investments and expects to reduce its annual emissions of sulfur dioxide by 36 percent and its "ozone-season" emissions of nitrogen oxides by 68 percent between 1999 and 2005. This testimony summarizes a May report, (GAO-01-658)."
Date: May 25, 2001
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department