Increasing Atmospheric Levels of 1,2,4-TMB in the DFW Metroplex from Natural Gas (Extraction) Processing from 2005 – 2015 and Asthma Rate




Calderon, Ebony
Hosseinzadehnaseri, Hadis
Rich, Alisa


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Introduction: 1,2,4-Trimethylbenzene (1,2,4-TMB) is an industrial solvent used in 21 different hydraulic fracturing fluids. 1,2,4-TMB is found to contribute to the formation of photochemical smog in the presence of other VOCs, which is known to exacerbate respiratory conditions. 1,2,4-TMB contributes to formation of Peroxyacetyl nitrate (PAN), a component of photochemical smog reactive to sunlight and a factor in ozone production. The purpose of the study was to examine the overall trend in atmospheric 1,2,4-TMB, and the rate of Asthma over the same time period. Methods: Ambient concentrations of 1,2,4-TMB were collected from the Texas Commission on Environmental Quality (TCEQ) database, and the U. S. Environmental Protection Agency’s Urban Air Toxics Monitoring Programs (UATMP) report from 2005-2013. Asthma data was collected on children and adults from the 2015 United Way Tarrant County Community Assessment (UWTCCA). Results: Based on TCEQ data, the average amount of 1,2,4-TMB has increased during the past decade. The maximum observed level of 1,2,4-TMB increased by 437.5% from 2008 to 2010, and concentrations were 790% higher from 2008-2009, 2,119% higher in 2010, and 10,747% higher in 2011 (Rich & Orimoloye, 2015) when compared to UATMP. The 2015 UWTCCA indicates a higher asthma prevalence in North Texas. In 2010, lower respiratory disease was ranked as the 4th leading cause of death in Tarrant County. Asthma among Tarrant County adults is 9.6% higher and 17.6% higher for children compared to Texas. 1,2,4-TMB is capable of producing PAN, a powerful respiratory irritant present in photochemical smog. Increasing levels of 1,2,4-TMB in the DFW area due to natural gas extraction may be a contributing factor to the increasing rates of asthma. 1,2,4-TMB is also a factor in smog production, a respiratory irritant and exacerbator of asthma. Conclusions: Increased atmospheric levels of 1,2,4-TMB was found in areas of natural gas extraction and processing in the DFW area. 124-TMB is a factor in PAN production and ozone, which are respiratory irritants. Fort Worth has a high rate of asthma, which may be associated with increased levels in 1,2,4-TMB, PAN, photochemical smog, and ozone.