Dust in the wind.
Henry
C
C
D000336:Aerosols / Q000032:analysis; D000393:Air Pollutants / Q000032:analysis* / Q000592:standards; D004784:Environmental Monitoring / Q000592:standards*; D010316:Particle Size; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods; D014481:United States; D014484:United States Environmental Protection Agency
D000336:Aerosols; D000393:Air Pollutants