Comparison Between PM2.5 Levels on East Coast and State of California in Relationship to Asthma

Rationale: Asthma is a chronic disease that causes swelling of the airways making it difficult to breathe. Common triggers that cause inflammation in the airway include pollen, smoke, stress, chemicals, and extreme weather changes, which may contribute to asthma. There is limited research that explains why California, despite many wildfires, has a lower prevalence of asthma compared to the east coast. Methods: Data on asthma prevalence, by state, for the year 2015 were obtained from Adults Asthma data collected via the Behavioral Risk Factor Surveillance System of the US Center for Disease Control and Prevention (CDC). PM2.5 concentrations for the year 2015 were retrieved from the publicly-available data from the Air Quality Index Report of the US Environmental Protection. Results: For the year 2015, the highest prevalence of asthma was among the east coast (all states that have shorelines on the Atlantic Ocean) with 9.2% of adults. Despite California being in the top two states for wildfires, it has one of the lowest prevalence asthma (7.7%) nationwide. When looking at the number of days PM2.5 was the main pollutant across each state, California had a 19% less days (128.2 days) than the east coast states (153.4 days). Conclusions: Different rates of asthma between different regions within the US may be due to different exposure risk to PM2.5 that originate from sources other than natural disasters, such as forest fires. Future studies should focus on other regions with regards to high PM2.5 levels in relationship to asthma.