Is your cell phone making you sick?

By Desiree McWhorter

Background Research

Bernd Hartman, et al; proposed an experiment testing computer user interfaces for potentially pathogenic microorganisms in an intensive care unit. The purpose of this study was to examine computer keyboards and mice for microbial contamination. The bedside computer interface of each of 14 patent rooms, as well as infusion pumps, ventilators, and the ward trolley were swabbed and then contained in a sterile solution for testing. In the central ward of the hospital, 16 swabs were taken from the keyboard and mouse of the physicians’ work station along with control buttons, the intercom and the telephone receiver. After testing they came to the conclusion that the electronic items that get heated up help grow bacteria and suggested that regular cleaning and disinfection of phones and keyboards etc. would be beneficial to your health and the people around you.

Hartmann, Bernd. "Computer Keyboard and Mouse as a Resvoir of Pathogens in an Intensice Care Unit." (2004).

Introduction

The purpose of this study is to test the number of everyday items that we think are clean, but actually are not. In this investigation, I will be testing the levels of microbial contamination that can be found among every day items including cell phones, door knobs, toilets, computer keyboards and toothbrushes. A number of samples will be taken from each of these items, and compared to a control group of sterile swabs. This testing will take place in a biology laboratory at the University of New Orleans. This experiment will allow me to determine which surfaces harbor the most biological contamination and pose the largest threat of infection.

Experimental Design DiagramHypothesis: I hypothesized the electronic items people use reguarly would contain the most microbial contamination.

Independent Variable: Colonies of Bacteria growth

Levels of IV 0-? 0-? 0-? 0-?

Trials 3 3 3 3

Dependent Variable: Items being tested (Door handles, Toilet seats ,Toothbrushes, cellphones, computer keyboards)

Controlled Variables (constants)Temperature (37degrees Celsius)

Materials and Equipment Procedures:

1) Label the Petri dishes for each of the samples being collected and tested.

2) Fill Petri dishes with Agar gel that was melted into a liquid.

3) Collect samples of all items being tested for microbial contamination.

4) The samples were all placed into an incubator at 37 degrees Celsius for 18 to 24 hours.

5) Remove the Petri dishes and count the colonies of bacteria that grow on them.

6) Divide the dishes into quadrants and use a permanent marker to dot them.

7) make a chart that shows how the results compare to each other for the different samples.

18 Petri dishes (three for each group, and three for the control group)18 sterile swabsAgar gel70% ethyl alcoholdistilled waterpermanent markerlatex gloves

POTENTIAL SOURCES OF MICROBIAL CONTAMINATION

SUBJECT SOURCE BACTERIA COUNT

CONTROL 1 STERILE COTTON SWAB 1

CONTROL 2 STERILE COTTON SWAB 0

CONTROL 3 STERILE COTTON SWAB 0

CELL PHONE 1 VOLUNTEER 1 45

CELL PHONE 2 VOLUNTEER 2 13 (1 FUNGI PRESENT)

CELL PHONE 3 VOLUNTEER 3 99

TOOTHBRUSH 1 VOLUNTEER 1 7

TOOTHBRUSH 2 VOLUNTEER 2 0

TOOTHBRUSH 3 VOLUNTEER 3 0

CONTINUED

CONTINUED

KEYBOARD 1 VOLUNTEER 1 LAPTOP 6

KEYBOARD 2 VOLUNTEER 2 LAPTOP 1(STREAK ERROR)

KEYBOARD 3 UNO LAB DESKTOP 138

DOOR KNOB 1 BIO BUILDING RM 230 0

DOOR KNOB 2 BIO BUILDING RM 217 0

DOOR KNOB 3 BIO BUILDING RM 204 1

TOILET 1 WOMEN'S BATHROOM 1

TOILET 2 WOMEN'S BATHROOM 5

TOILET 3 WOMEN'S BATHROOM 1

Data Analysis

Pictures taken of Student preparing material

The two photos above show the three trials of the control and cell phones. In the cell phone you can see the different levels of bacteria of each phone.

P2 represents phone number two and this was the only phone that contain a fungus. K2 is keyboard 2 the is a streak error caused by too much solution on the swab.

Conclusion

After my experimentation, and reviewing of my result I concluded the my Hypothesis, that the items that were electronic and used regularly contain the highest levels of microbial contamination. My studies indicate that these every day items are often more filthy than your toilet seat, which only contained a very small amount of bacteria. This means that even though we may clean our house religiously, it may be the things we carry with us that have the highest risk of making us sick. Consider wiping you computer and cell phones down with antibacterial wipes to avoid the risks of infections.

Works Cited

MLA

Hartmann, Bernd. "Computer Keyboard and Mouse as a Resvoir of Pathogens in an Intensice Care Unit." (2004).