Date of Award
Doctor of Philosophy
Environmental Science and Engineering
Thomas E. Gill
The Southwestern region has been identified as one of the most persistent dust producing regions of North America. Exposure to inhalable particulate matter (PM10) originating from desertic landscape during dust events/dust exposures (DEs) can reach hazardous levels. El Paso, Texas’s ambient air has reached hazardous levels of PM10 above 4000 μg/m3 with near zero visibility due to these natural events. There are very few prior studies in the southwestern United States pertaining to the associations between exposure to atmospheric aerosol after DEs and hospitalizations, nor are there many epidemiological studies globally in dusty environments where most of the atmospheric aerosol is soil derived. Therefore, the relationship between dust exposure and hospital admissions due to neurodegenerative diseases (ND), mental illness (MI), Valley fever (VF), Asthma, Coronary Atherosclerosis, Associated Diseases (AD), and ICD-9 category and the modifying effect of the demographic factors (age, income and education attainment) was assessed at the County of El Paso, TX.
A conceptual model with all predictive and response variables with model equations was performed to analyze most factors influencing hospitalizations during DE in El Paso. The predictive model was able to describe factors related to hospitalization during blowing dust events and to predict future hospitalization rates based on dust events. This model analysis may be applied using data mining in other arid locations. Descriptive data results showed that from 2010-2014 there were more hospitalizations in a DE (62%) than in a regular day (RD) (38%). During DE there was a factor of 11.38% more hospitalizations due to acute conditions; 11.81% more from chronic conditions and 1.53% more from mental health than in a regular day.
An intelligent tool was developed using Case-based Algorithm based on Ant Colony Algorithm and the programming language Java (J2SE). Proposed algorithm helps to improve the ambulance routing demand by 35% of cases during and after a DE in El Paso County. Using Bluetooth, it is possible to use our proposed model of ambulances in an emergency related to a severe dust storm. In addition, a Kriging Model of incidence with birth cases (single liveborn, delivered by cesarean section) was performed, and shows that in the predicted future of increasing dust storms there will be a necessity of more ambulances to transport more patients during a dust event.
Using a Poisson regression, it was found that the relative risk of hospitalizations due to VF, coronary atherosclerosis, genitourinary diseases, ND, injury and poisoning, circulatory system conditions, respiratory system diseases, births, septicemia, AD and all ICD-9 admissions were significantly positively associated with DE (through increases of at least 100 micrograms per cubic meter of daily maximum hourly PM10, and/or increases of at least 10 mph in daily hourly average wind speed in El Paso, Texas between 2010 and 2014, at different lag periods after exposure, indicated from higher to lower significant risk. Patients with medium and low socio-economic status showed a significant need to pay for their chemotherapy services; circulatory system conditions; aftercare services; and injury and poisoning associated with a DE. As age decreases, the chances of a patient being hospitalized due to AD after a DE increases.
Recommendations for reduction of outdoor and indoor exposures to DE should be generated for El Paso County. Public policies and individual actions are essential to reduce the human health effects of DE. Due to forecasts that suggest DE will continue to rise an additional urgency of public policies to reduce DEs need to be taken, such as physical wind erosion control measures such as paving roads and reforestation. Individual actions need to be taken e.g., avoiding outdoor activities, wearing a mask and eye coverings during a DE, improving household insulation, and raising an environmental conscience.
Received from ProQuest
Estrella de Jesus Herrera-Molina
Herrera-Molina, Estrella de Jesus, "Associations Between Exposure To Air Pollution After A Dust Event And Hospitalizations." (2021). Open Access Theses & Dissertations. 3267.