Comparison of Atmospheric Volatile Organic Compounds (VOCs) in Unconventional Shale Gas Extraction and Production Areas and the 2008/09 and 2010 U.S EPA Urban Air Monitoring Program (UATMP)




Negedu, Grace
Uche, Uloma I.
Rich, Alisa


0000-0003-1887-3419 (Uche, Uloma I.)

Journal Title

Journal ISSN

Volume Title



Purpose: This study analyzed if VOC levels in the atmosphere were elevated in areas of energy E&P. Results were compared to ambient air sampling data from U.S. EPA Urban Air Toxic Monitoring Program (UATMP) using 2008/2009 and 2010 data. The UATMP is the most comprehensive air monitoring program in the U.S. Methods: Ambient air sampling occurred in 6 counties in the Dallas/Fort Worth (DFW) Metroplex from 2008 – 2010 using certified sterilized evacuated stainless steel 6 liter summa canisters. Air samples were analyzed by GC/MS (Gas Chromatography Mass Spectrometry) following U.S. EPA Compendium Method Toxic Organics (T0-14A). Results: Ambient air sampling confirmed the presence of 106 VOCs however, 37 chemicals were comparable between the Barnett Shale study and UATMP. For 2008/09, 25 out of 37 compounds were elevated in the Barnett Shale over UATMP. Significantly elevated compounds include hexachlorobutadiene (+1429.41%), 1,2,4-trichlorobenzene (+2268.42%), m&p – xylene (3284.38%), benzene (+5432.71%), 3-methylhexane (+6000.80%), ethylbenzene (+6707.23%), 1,1,2,2- tetrachloroethane (+20,500%). For 2010, 30 out of 37 compounds were elevated in the Barnett Shale over UATMP. Significantly elevated compounds included dichlorotetrafluoroethane/F114 (+1036.36), toluene/methylbenzene (+1115.86%), tetrachloroethene/PCE (+1121.11%), ethylbenzene (+1458.62%), 1,2-dichloroethane/EDC (+1539.34%), trichloroethylene/TCE (+3302.23%), 1,3,5–trimethylbenzene (+5520.86%) hexachlorobutadiene (+7778.79%), m&P- xylene (+8085.19%), 1,2,4-trimethylbenzene (+10,647.33%), 1,1,2,2-tetrachloroethane (+17,066.67%), 1,2,4-trichlorobenzene (+20,049.25%), benzene (+21,745%). Conclusions: This study confirms energy extraction and production contributes to elevated levels of VOCs in the atmosphere impacting ozone levels. VOCs found in this study are considered to be hazardous air pollutants (HAPs), primarily for the impact to human health. Exposure to HAPs have been associated with elevated incidence in birth defects, cancers, immune and nervous system disorders.