Comparative biological potency of acidic sulfate aerosols: Implications for the interpretation of laboratory and field studies

Journal Article · Fri Apr 01 04:00:00 EST 1994 · Environmental Research; (United States)

DOI:https://doi.org/10.1006/enrs.1994.1022· OSTI ID:7074892

Schlesinger, R B; Chen, Lung Chi ^[1]

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1. New York Univ. Medical Center, NY (United States)

Biological responses to inhaled acid sulfates result from the deposition of hydrogen ion (H[sup +]) on airway surfaces. Thus, effects from sulfuric acid and ammonium bisulfate, the two major ambient species, have been assumed to be the same for a given H[sup +] concentration within the exposure atmosphere, assuming similar respiratory tract deposition patterns. However, recent inhalation studies have indicated that sulfuric acid is disproportionately potent compared to ammonium bisulfate when the H[sup +] content of the exposure atmosphere is considered, suggesting that some factors following inhalation affect the amount of H[sup +] contacting airway surfaces. This study assessed a mechanism potentially underlying this phenomenon, namely, the extent of neutralization by respiratory tract ammonia. This was evaluated using a physical model system designed to mimic transit of these aerosols in the upper respiratory tract of the animal model used in this laboratory, the rabbit. The results suggest that for equal exposure quantities of H[sup +], more acid would be deposited when sulfuric acid is inhaled than when ammonium bisulfate is inhaled. Furthermore, results from a series of in vitro exposures of tracheal epithelial cells to sulfuric acid and ammonium bisulfate aerosols indicated that the biological response is a function of the total mass (ionic) concentration of H[sup +] deliverable to the cells or the total extractable H[sup +] per particle. The results of this study have possible implications for ambient monitoring of particulate-associated strong acidity, suggesting that it may be necessary to speciate such measures into the relative amounts of H[sup +] as sulfuric acid or ammonium bisulfate in order to most accurately relate atmospheric acid levels to observed health effects. 29 refs., 5 figs., 2 tabs.

• OSTI ID: 7074892
• Journal Information: Environmental Research; (United States), Journal Name: Environmental Research; (United States) Vol. 65:1; ISSN ENVRAL; ISSN 0013-9351
• Country of Publication: United States
• Language: English

Related Subjects

550200 -- Biochemistry
560300* -- Chemicals Metabolism & Toxicology
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ACID SULFATES
AEROSOLS
BIOLOGICAL EFFECTS
COLLOIDS
COMPARATIVE EVALUATIONS
CONCENTRATION RATIO
DISPERSIONS
DOSE-RESPONSE RELATIONSHIPS
EVALUATION
HYDROGEN COMPOUNDS
INORGANIC ACIDS
OXYGEN COMPOUNDS
RESPIRATORY SYSTEM
SENSITIVITY ANALYSIS
SOLS
SULFATES
SULFUR COMPOUNDS
SULFURIC ACID