A recent study led by Harvard T.H. Chan School of Public Health has identified the components of fine particulate air pollution (PM2.5) that most strongly contribute to hospitalization among asthma sufferers. The study found that metals, particularly nickel and vanadium, along with sulfate particles, are the key components of PM2.5 that increase the risk of asthma exacerbation and hospitalization.
According to Joel Schwartz, professor of environmental epidemiology and corresponding author of the study, understanding which specific compounds in the PM2.5 mixture are most harmful is crucial for improving asthma outcomes. The study, published in the American Journal of Respiratory and Critical Care Medicine, analyzed the joint impact of various pollutants composing PM2.5 on asthma exacerbation.
Previous studies have mainly focused on individual pollutants or PM2.5 as a whole. However, this study took a middle-ground approach by identifying the specific compounds in PM2.5 and their collective impact on asthma hospitalizations. Using machine learning algorithms, the researchers identified a list of compounds, including nickel, vanadium, sulfate, and others, as the key components of PM2.5.
The study utilized data from 11 states between 2002 and 2016 to assess the total number of asthma hospitalizations and estimate the annual levels of each compound at a U.S. zip-code level. Controlling for variables such as outdoor temperature and socioeconomic status, the researchers found that nickel, vanadium, sulfate, nitrate, bromine, and ammonium were the compounds that contributed the most to asthma hospitalizations.
To reduce asthma hospitalizations, the researchers recommend better control of sources that emit these harmful compounds. For example, nickel and vanadium are produced from burning fuel oil, while sulfates come from coal combustion. Implementing measures like scrubbers on coal plants and transitioning to less polluting fuels can help mitigate the impact of these pollutants on asthma sufferers.
Further research is needed to understand how specific particles in the PM2.5 mixture affect asthma hospitalizations after short-term exposure. The study highlights the importance of targeted interventions to reduce the health burden of air pollution on asthma patients.
The study was co-authored by researchers from Harvard Chan School of Public Health, including Bryan Vu, Xinye Qiu, Yijing Feng, and Yaguang Wei. For more information, the study is available in the American Journal of Respiratory and Critical Care Medicine under the DOI 10.1164/rccm.202409-1853OC.
This research sheds light on the specific components of air pollution that pose the greatest risk to asthma sufferers, offering insights for policymakers and public health officials to develop targeted strategies for reducing asthma exacerbations and hospitalizations related to air pollution.
