Exploratory study of seasonal indoor bioaerosols and the associated health outcomes in low-income communities in El Paso, Texas, 2014

Eric Martinez, University of Texas at El Paso


Introduction: Structural degradation, moisture levels, and building failures can influence poor indoor air quality and create a good environment for bioaerosols. People spend much of their time indoors and can potentially be exposed to these bioaerosols. Several studies have correlated exposures to high concentrations of bioaerosols to various health problems, severe allergies, asthma, or other respiratory illness. Objectives: The objectives of this study are to describe bioaerosol concentrations, meteorological factors, and health outcomes during the summer and fall seasons; characterize bioaerosols (bacteria and fungi) collected in low-income communities; compare bioaerosol concentrations by season; compare meteorological factors to bioaerosol concentrations by season; and compare health outcomes associated with bioaerosols by season. Methods: Indoor air quality measurements for bioaerosols were conducted in the morning for two seasons using an Andersen 2-stage cascade impactor. A health quality questionnaire was given to assess reported health outcomes of low-income residents as well as a technical survey administered to check house conditions, which may be potential factors for bioaerosols. Bacterial and fungal colonies were counted and identified in the laboratory. Findings: Overall, 45 houses were sampled for the summer and fall season. Majority of the bacteria found was non-pathogenic or opportunistic to those who are immunocompromised. Some important pathogens to consider were Streptococcus pneumoniae and methicillin resistant S. haemolyticus and S. auricularis. The identified fungi are considered to be aeroallergens with the capacity to release spores and cause allergic reactions. Concentrations for bacteria were highest for fine bacteria (134 CFU/m3) during the fall, while fungi concentrations were highest for fine fungi (438 CFU/m3) during the summer. A Wilcoxon signed-rank test showed that both fine and coarse bioaerosol concentrations did elicit a statistically significant change between summer and fall (p < 0.001). When reporting meteorological factors, low-income communities had a higher mean temperature (27.58°C) and relative humidity (56.97%) in the summer than in the fall. During the summer, participant’s highest reported health outcomes were allergies (60%), stuffy nose (60%) and skin irritation (56%) while runny nose (84%), cough (80%), and stuffy nose (71%) were more prevalent during the fall. There was a statistically significant difference in the proportions of reported health complains for wheezing, dry eyes, cough, sneezing, stuffy nose, runny nose, and throat infection between the summer and fall. (p =0.031, p =0.004, p =0.001, p =0.004, p =0.013, p =0.006, p =0.017) Discussion: Different bacteria and fungi were reported during the summer and fall. Study findings also indicate a statistically significant difference in both coarse and fine bioaerosol concentrations for fungi and bacteria by season. In addition there was no correlation between temperature and bioaerosols or between bioaerosols and RH. Some of the reported health outcomes by participants were associated to the different seasons, with higher reported health outcomes in the fall. As per our knowledge, this is the first study conducted in El Paso to characterize and correlate bioaerosols throughout two distinct seasons involving low-income communities. The information obtained will help to develop future interventions and guidelines on how to have better indoor air quality and reduce exposure to bioaerosols.

Subject Area

Microbiology|Environmental Health|Public health

Recommended Citation

Martinez, Eric, "Exploratory study of seasonal indoor bioaerosols and the associated health outcomes in low-income communities in El Paso, Texas, 2014" (2015). ETD Collection for University of Texas, El Paso. AAI1600331.