Effects of exercise exposure on toxic interactions between inhaled oxidant and aldehyde air pollutants

Journal Article · Fri Jan 01 00:00:00 EST 1988 · J. Toxicol. Environ. Health; (United States)

DOI:https://doi.org/10.1080/15287398809531198· OSTI ID:6554164

Mautz, W J; Kleinman, M T; Phalen, R F; Crocker, T T

Respiratory tract injury resulting from inhalation of mixtures of ozone (O3) and nitrogen dioxide (NO2) and of O3 and formaldehyde (HCHO) was studied in Sprague-Dawley rats under exposure conditions of rest and exercise. Focal inflammatory injury induced in lung parenchyma by O3 exposure was measured morphometrically and HCHO injury to the nasal respiratory epithelium was measured by cell turnover using tritium-labeled thymidine. Mixtures of O3 (0.35 or 0.6 ppm) with NO2 (respectively 0.6 or 2.5 ppm) doubled the level of lung injury produced by O3 alone in resting exposures to the higher concentrations and in exercising exposures to the lower concentrations. Formaldehyde (10 ppm) mixed with O3 (0.6 ppm) resulted in reduced lung injury compared to O3 alone in resting exposures, but exercise exposure to the mixture did not show an antagonistic interaction. Nasal epithelial injury from HCHO exposure was enhanced when O3 was present in a mixture. Mixtures of O3 and NO2 at high and low concentrations formed respectively 0.73 and 0.02 ppm nitric acid (HNO3) vapor. Chemical interactions among the oxidants, HNO3, and other reaction products (N2O5 and nitrate radical) and lung tissue may be the basis for the O3-NO2 synergism. Increased dose and dose rate associated with exercise exposure may explain the presence of synergistic interaction at lower concentrations than observed in resting exposure. No oxidation products were detected in O3-HCHO mixtures, and the antagonistic interaction observed in lung tissue during resting exposure may result from irritant breathing pattern interactions.

• Research Organization: Univ. of California, Irvine (USA)
• OSTI ID: 6554164
• Journal Information: J. Toxicol. Environ. Health; (United States), Vol. 25:2
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
59 BASIC BIOLOGICAL SCIENCES
EXERCISE
BIOLOGICAL EFFECTS
FORMALDEHYDE
TOXICITY
NITROGEN DIOXIDE
OZONE
RESPIRATORY SYSTEM
SENSITIVITY
AIR POLLUTION
DOSE-RESPONSE RELATIONSHIPS
INHALATION
RATS
SYNERGISM
TRACER TECHNIQUES
TRITIUM COMPOUNDS
ALDEHYDES
ANIMALS
CHALCOGENIDES
INTAKE
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
MAMMALS
NITROGEN COMPOUNDS
NITROGEN OXIDES
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
POLLUTION
RODENTS
VERTEBRATES
560300* - Chemicals Metabolism & Toxicology
550501 - Metabolism- Tracer Techniques