Smartphones are chock full of allergens, asthma triggers, study finds

Nov. 10 (UPI) -- Smartphones are found everywhere, handled and viewed constantly -- and, as it turns out, a bountiful source of elevated levels of allergens and asthma triggers.

But the devices can be cleaned effectively -- and should be cleaned more often -- to minimize exposure.

That's according to new research being presented at the American College of Allergy, Asthma and Immunology's annual scientific meeting in Louisville, Ky., that began Thursday.

For the study, the scientists used electrostatic wipes to sample simulated phone models of 15 volunteers and then measured the "phones" for levels of allergens, as well as Beta-glucans -- known as BDGs, a marker for mold -- and endotoxins, found in gram-negative bacteria.

"Smartphones showed elevated and variable levels of BDG and endotoxin, and cat and dog allergens were found on smartphones of pet owners," Hana Ruran, a high school senior from Hopkinton, Mass., the study's lead author said in a news release.

Ruran presented the research, which stemmed from her science fair project, at the scientific conference.

Ruran explained that BDGs are found in fungal cell walls "and have been found in many environments and surfaces causing chronic airway and irritant symptoms -- making BDGs a consistent marker to study problematic mold."

She described endotoxin as "a potent inflammatory agent and a marker of exposure to Gram negative bacteria."

Next came a look at effective cleaning tools.

The researchers tested a mixture of chemicals in cleaning solutions -- chlorhexidine, cetylpyridinium chloride, tannic acid and benzyl benzoate -- that they said can be purchased through laboratory or chemical suppliers, but are not commercially available in the same concentrations as used in the study.

Isopropyl alcohol wipes also were tested for their cleaning properties.

"Combination chlorhexidine/cetylpyridinium was the most effective in reducing BDG and endotoxin and combination benzyl benzoate/tannic acid most effectively reduced cat and dog allergens on smartphones," said Peter Thorne, Ruran's mentor and the study's co-author, whose lab was involved in the study.

Thorne, a professor in the University of Iowa College of Public Health's Department of Occupational & Environmental Health, previously chaired the U.S. Environmental Protection Agency's Science Advisory Board.

Thorne said the study "demonstrates exposure to inhalant allergens and molecules that trigger innate immune reactions from a source most people haven't considered."

People with allergies or asthma may want to consider cleaning their smartphones more often to minimize exposure to these allergens and asthma triggers, he added.