Science Wednesday: From Iceland’s Ash, Potential Particle Insights

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The recent volcanic eruption in Iceland has focused international attention on tiny particles called aerosols that have been the subject of scientific scrutiny at EPA for decades.

Much of this week’s media frenzy has focused on airport chaos related to the eruption, but the potential health impacts to those breathing the volcanic aerosols also deserve consideration.

Though the particles from Iceland’s plume vary considerably in makeup from the particles EPA typically investigates (from vehicles, factories, and dust), the eruption may contribute to our general understanding of airborne particles and their potential health impacts.

According to Daniel Costa, EPA’s national program director for air research, volcanic ash is not nearly as toxic to the lungs as particles from typical urban sources, like traffic. However, he explained, they “may result in coughing and sneezing,” and may be especially irritating to “asthmatics and people with cardiopulmonary disease.”

Costa and other EPA scientists and grantees have previously studied the health effects of particles from Mount St. Helen’s, a volcano in Washington State that erupted violently in 1980.

According to accounts of the eruption from the National Forest Service, “a mushroom-shaped column of ash rose thousands of feet skyward and drifted downwind, turning day into night as dark, gray ash fell over eastern Washington and beyond.”

While “pound for pound, volcanic ash is much, much less toxic than typical air pollution particles,” Costa said, “…when combined with dust, sulfur dioxide and other gaseous emissions from volcanic emissions may be pretty potent acting through different pathways with the same result.”

After the Mount St. Helen’s eruption, scientists spent years studying, observing and analyzing data from the event. Air pollution experts at EPA believe more could potentially be learned from future studies of Iceland’s far-reaching plume.

volcano_1-usgsBryan Bloomer, atmospheric scientist at EPA’s National Center for Environmental Research, said that “for meteorologists, atmospheric scientists, and climate scientists, it will be interesting to watch.”

“There is a lot to be learned about wind currents from the movement of the plume, the application of remote sensing and satellite imagery to aerosol modeling, and also observations we can make about the effects of the eruption on temperature.”

Shockwaves from the eruption are mostly being felt abroad, but resulting awareness of airborne particles as a health threat should resonate right here at home, where particle pollution of a different sort remains a major environmental policy priority. 

About the Author: Becky Fried is a science writer with EPA’s National Center for Environmental Research and a regular contributor to Science Wednesday.

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