Tools for Assessing Respiratory Risk in Vulnerable Populations

Abstract

Air pollution is a substantial environmental risk factor accounting for an estimated 6.6 million premature deaths annually. Pregnant women and infants are biologically susceptible to adverse effects of air pollution exposure. Moreover, the inability to mount an effective oxidative stress response can exacerbate effects. In general, air pollution exposure disproportionately effects socioeconomically disadvantaged communities, often minority populations, residing near industrial facilities. Given the limitations of current understanding of the underlying mechanisms of action, especially for an emerging class of pollutants, ultrafine particles (UFP) and weaknesses in current methods used in assessing air pollution exposure, especially complex mixtures, our objective was to apply novel tools for assessing respiratory risks in vulnerable populations. The gut microbiome has recently gained recognition as a promising tool in maintaining respiratory health. Consequently, we first evaluated the relationship between gut microbiome and NRF2 response to UFP induced oxidative stress in pregnant mice. In this study, we found no differences in the gut microbiome indices between C57Bl/6 wild type and NRF2 knockout mice gestationally exposed to 100µg/m3 UFP. In a second study, we found a decreasing trend of gut microbial diversity and significantly decrease abundance of beneficial Bifidobacterium and Bacteroides genera in C57Bl/6 neonatal mice exposed to 7 days of 200µg/m3 UFP. Findings here indicate a gut microbiome mediated outcome to developmental UFP exposures. Finally, we characterized ambient respiratory risk to volatile organic compounds in environmental justice communities using a newly developed mobile laboratory equipped with a proton transfer reaction mass spectrometer for real time high fidelity spatial air quality mapping. In this study, we identified specific temporospatial differences to VOC mixture exposures in these communities. In general, these studies developed a novel tool in accessing exposure risk to air pollution and an underlying mechanism of adverse outcome in vulnerable populations.