skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Consideration of air quality standards for vegetation with respect to ozone

Journal Article · · J. Air Pollut. Control Assoc.; (United States)

Present evidence suggests that ozone is the most damaging of all air pollutants affecting vegetation. It is the principal oxidant in the photochemical smog complex. Concentrations of ozone have exceeded 0.5 part per million (ppm) in the Los Angeles area. One-tenth of this level for 8 hours is known to injure very sensitive tobacco varieties. Many plant species are visibly affected after a few hours exposure at concentrations much lower than 0.5 ppm. There is also some evidence that ozone reduces plant growth. Many factors must be taken into account when considering standards to protect vegetation from ozone damage. These include ozone concentration and methods of measurement, time of exposure, possible additive effects of other pollutants, sensitivity of plant species, their economic value, and the extent of injury which can be tolerated. The response of a species to the pollutant is conditioned by genetic factors and environmental conditions. Lack of specific routine methods for measuring ozone in ambient air is a handicap. California and Colorado established standards for oxidants at 0.15 and 0.10 ppm, respectively, for 1 hour. How these standards relate to the ozone dosage causing acute and chronic injury to various plant species is discussed.

Research Organization:
Dept. of Agriculture, Beltsville, MD
OSTI ID:
6415009
Journal Information:
J. Air Pollut. Control Assoc.; (United States), Vol. 19:6
Country of Publication:
United States
Language:
English