Background: Eight-four percent of people own smartphones and view them 14 billion times daily, making them potential vectors for environmental hazards such as allergens, β-D-glucans (BDGs), and endotoxin. Whether these toxins are prevalent and the effectiveness of cleaning solutions targeting these agents on smartphones have not been studied.
Objective: We sought to determine (1) whether phones are reservoirs of allergen, endotoxin, and BDGs and (2) if present, whether their levels can be effectively reduced by using specific cleaning methods.
Methods: Electrostatic wipes used to wipe the phones of 15 volunteers were tested to determine their allergen, BDG, and endotoxin levels. Cleaning interventions were done on simulated phone models; 70% isopropyl alcohol, 0.184% benzyl and ethyl benzyl ammonium chloride (Clorox nonbleach [The Chlorox Company, Oakland, Calif]), 0.12% chlorhexidine, 0.05% cetylpyridinium, 3% benzyl benzoate, and 3% tannic acid wipes were used and compared with wipes with no solution (the control).
Results: The smartphones showed high and variable levels of BDG and endotoxin. Cat and dog allergens were found mostly on the smartphones of pet owners. The combination of chlorhexidine and cetylpyridinium significantly reduced BDG levels (mean 269 ng/wipe vs 1930 ng/wipe for the control [P < .05]) and endotoxin, (mean 349 vs 1320 endotoxin units/wipe for the control [P < .05]). The combination of benzyl benzoate and tannic acid significantly reduced the levels of cat and dog allergens (dog, mean level of 14 ng/wipe versus 407 ng/wipe for the control [P < .001]; cat, mean level of 55 ng/wipe versus 1550 ng/wipe for the control [P < .001]). The combination mixture solutions had the greatest reductions compared with the control.
Conclusions: There are elevated levels of BDG, allergens, and endotoxin on smartphones. The combination of chlorhexidine and cetylpyridinium was the most effective in reducing BDG and endotoxin levels, and the combination of benzyl benzoate and tannic acid was most effective in reducing cat and dog allergen levels on smartphones.
Keywords: Allergens; cleaning solution; endotoxin; environmental exposures; smartphones; β-D-glucans.