“Believe it or not, the air has gotten better,” the headline of Jay Evensen’s recent well-intentioned opinion piece about air quality along the Wasatch Front, makes for a good tourism slogan, but it misrepresents the status of Utah’s air. Evensen omitted some important information, leaving the mistaken impression that the air quality problem in Utah is trending in the right direction.
First, the average annual Air Quality Index (AQI) Evensen refers to is not a good indicator of how air pollution affects our health and whether the air is truly “getting better.” Averaging the bad air and good air days hides the seriousness of very unhealthy air quality periods like this past week. Most of Utah’s metropolitan areas currently do not meet federal air quality standards because of the number of days each year they exceed unhealthy air pollution thresholds, not because of the average AQI over the course of a year.
Second, the AQI is a composite number that represents five different types of pollutants. Some of them are visible and others are not, and the proportion of each has changed over time. In 1950, the angry caller Evensen mentions was probably complaining about coal soot from home furnaces. In 1980, the major pollutant was sulfur dioxide, which has serious but short-term health effects. Today, the major air pollutants are fine particulates and ozone, which have longer-term but equally serious health effects, even with intermittent exposures.
Third, Evensen referenced Gov. Gary Herbert’s claim that “emissions fell by 46 per capita” over the most recent 12-year period of rapid population growth. Combining emissions per capita with the “improvements” represented by the average annual output of air pollutants only tells us that there are more of us breathing the same high concentration of particulates during inversions.
It will take the combined efforts of policymakers, regulators and businesses, as well as individual lifestyle changes, to make sure that we have fewer bad air days and that the state remains a place that tourists want to visit, businesses want to locate, and people want to live.
Scott Williams, executive dircetor of HEAL Utah
Salt Lake City