Public health ... smog clogs urban EDs.
D004636:Emergency Service, Hospital / Q000706:statistics & numerical data; D006801:Humans; D011634:Public Health / Q000331:legislation & jurisprudence; D012140:Respiratory Tract Diseases / Q000453:epidemiology; D012905:Smog / Q000009:adverse effects*; D014481:United States / Q000453:epidemiology; D014504:Urban Health
D012905:Smog