title: The influence of chemical and physical forms of ambient air acids on airway doses.
abstract: The effects of ambient relative humidity and particle size on acid deposition within the airways have been examined with a computer model. For H2SO4 particles initially at 90% relative humidity in ambient air that are inhaled via the nose or mouth, there is significant deposition of acid in the airways even in the presence of typical values of respiratory NH3. When these same particles are found in a fog at 100.015% relative humidity, there is significant deposition of acid in the nasal region during nose breathing but insignificant deposition to the deep lung for either nose or mouth breathing. The factors governing the partitioning of labile acid gases in the gas and liquid phases prior to inhalation are also discussed.
authors.affiliation: Department of Civil Engineering, University of Washington, Seattle 98195.
authors.forename: T V
authors.initials: TV
authors.lastname: Larson
mesh_terms: D015258:Acid Rain / Q000009:adverse effects*; D000336:Aerosols; D000393:Air Pollutants / Q000009:adverse effects*; D006801:Humans; D009566:Nitrates / Q000009:adverse effects; D017942:Nitric Acid; D010316:Particle Size; D012140:Respiratory Tract Diseases / Q000209:etiology*; D012307:Risk Factors; D013458:Sulfur Dioxide / Q000009:adverse effects; D013464:Sulfuric Acids / Q000009:adverse effects
chemical_list: D015258:Acid Rain; D000336:Aerosols; D000393:Air Pollutants; D009566:Nitrates; D013464:Sulfuric Acids; D013458:Sulfur Dioxide; D017942:Nitric Acid; C033158:sulfuric acid