Overview

• Nickel and vanadium metals, along with sulfate particles, were identified as the strongest contributors within the PM2.5 mixture associated with increased asthma hospitalizations.
• Each decile increase in the modeled mixture corresponded to a 10.6% rise in hospitalizations among children and an 8% rise among adults aged 19–64.
• The analysis also assigned notable weight to nitrate, bromine, and ammonium, indicating multiple contributors within the fine-particle mixture.
• Using zip-code–level estimates and weighted quantile sum regression, the study evaluated 469,005 hospitalizations across 11 U.S. states from 2002 to 2016.
• The peer-reviewed work, led by Harvard T. H. Chan School of Public Health and published in the American Journal of Respiratory and Critical Care Medicine, points to source controls on fuel-oil and coal combustion as actionable steps and calls for research on short-term exposure effects.