Increased Risk of Trisomy 18 Observed after a Fertilizer Warehouse Fire in Brazos County, TX

Abstract

TPS 911: Air pollution, epigenetics, biomarkers, Exhibition Hall, Ground floor, August 26, 2019, 3:00 PM - 4:30 PM Trisomy 18 (T18) is the second most common autosomal chromosomal disorder due to the presence of extra chromosome 18 after trisomy 21 (T21). However, the causes of T18 remain unknown. In 2009, a fire accident occurred in a fertilizer warehouse in Brazos County, Texas. It caused extensive flames and smokes, which resulted in evacuating the south of town. The potential impacts of this accident-related pollution on birth outcomes (or congenital malformations) has rarely been studied. In this study, we assessed the effects of exposure to pollution from this fire accident on Trisomy 21 (T21) and Trisomy (T18), two of the most common chromosome abnormalities, using Texas birth defect data and live birth data. The changes in prevalence of T18 and T21 before (2005-2008), during the impacted years (2009-2010, i.e. current year and one year after the accident) and after the accident (2011-2014) were analyzed, respectively. Standardized Morbidity Ratio (SMR) was applied to examine the elevated risk of chromosomal anomalies as compared to the statewide risk after adjusting for maternal race and age. The prevalence of T18 was significantly higher during the impacted years (2.5%-5.7%) than those in the years before and after the accident (0%-1.3%). Comparing to the statewide risk, the risk of T18 during the impacted years in Brazos county was significantly higher (SMR=5.0, 95% CI: 2.19-9.89) while there was no significant difference before (SMR=0.77, 0.13-2.54) and after the accident (SMR=0.71, 0.12-2.36). However, the prevalence of T21 during the impacted years was not significantly different from those before or after the accident. No elevated risk of T21 during the impacted years was observed as compared to the statewide level. This study suggested that this fertilizer fire may be related to the increased risk of T18 in Brazos County, TX. The findings warrant further investigation.