Konnie Zimmerman '12

Talking Dirty? How Contaminated Is Your Mobile Phone?

Talking dirty has an entirely new meaning these days. Mobile phones have become a necessity to keep in contact with family and friends, but are now common within the work place, even healthcare and foodservice workers. These work environments have contact with people and food so the potential for transferring bacteria to individuals is high.

The purpose of this study is to determine contamination on various styles of mobile phones and the efficacy of different disinfectants to sanitize to limit the transfer of bacteria.

Methods: Thirty-four phones were collected from college students and divided between the four disinfectants (Clorox Wipes, 7th Generation Wipes, Wet Ones, and 70% Alcohol Wipes), containing different active ingredients. Each disinfectant was tested with a variety of phone styles (Smartphone, Slider/Swivel, Flip, Blackberry). These phones were swabbed with a 3M Quick Swab prior to disinfectant use. Each phone was swabbed again after being cleansed and air dried for a minimum of 10 minutes. Media from swabbing were transferred to 3M Petrifilm Aerobic Count plates and 3M Petrifilm E. Coli/Coliform Count plates and incubated at 35 degrees for 48 hours.

Results: 100% of the cell phones were contaminated. Contamination ranged from 1-560 colonies per student cell phone. Smartphones had the highest average colony count (18 phones; 57 average colonies), followed by Slider/Swivel phones (10; 34), flip phones, and then Blackberry phones. Subjects (n=30) completed a questionnaire: 67% never cleaned their phones, although 53% washed their hands 5-10 times/day with 93% using soap and hot water. A paired t-test was used to analyze data. The effect of disinfectants was statistically significant (P=0.01), reducing bacteria on contaminated cell phones by an average of 83% (78%-87%). Each disinfectant wipe appeared to be equally effective regardless of colony count or style of cell phone.

Conclusion: Mobile phones are indeed contaminated with bacteria and regular cleaning with commercial wipes regardless of active ingredients has a significant impact on lowering the overall risk of contamination.

To view Poster, click on link below:
Talking Dirty? How Contaminated Is Your Mobile Phone?

Research Advisor: Amy Olson, PhD, RDN, LD