Bacteria test: How many bacteria are there on a mobile phone that is used for 8 hours a day?

The third wave of free total colony count testing is here!

Previously, through the "old for new" campaign, we provided fans with free tests on the total number of colonies on beauty sponges and yoga mats (click on the blue words to review). Now it's finally the turn of mobile phones, which everyone is more concerned about.

This time, not only the mobile phone films will be tested, but also the mobile phone cases.

Let's take a quick look at how dirty your phone is, as it is often taken to the toilet and bed and is always in contact with your hands and face. Which is dirtier, the phone film or the phone case?

Disclaimer: This evaluation of Zhishang Life Circle does not contain any commercial advertisements. The test results are only responsible for the samples provided and do not represent the situation of similar products.

We sent the 3 collected mobile phone film samples and 3 mobile phone case samples to the microbiology laboratory for total colony count testing.

Ding ding ding ding, after a series of experiments, the test results of the total colony count of mobile phone films and mobile phone cases are finally out.

The purchase time of the three mobile phone film samples varies greatly, with the shortest being only half a month and the longest being two and a half years. However, the daily usage time is very long, and sample 1 and sample 3 even have the habit of using them in the toilet.

Surprisingly, their total colony counts did not exceed 100 CFU/sheet.

Sample 1, which had been used the longest, was often taken into the toilet and had never been cleaned, had the lowest total colony count, only 20 CFU/sheet.

Sample 2, which has the second highest total colony count, is used for a shorter period of time than the other two samples and is rarely taken to the toilet. However, this may be because the owner has sweaty hands, which creates a humid environment conducive to the reproduction of bacteria. Therefore, the total colony count detected is not the lowest - 60 CFU/sheet.

Sample 3 has the highest total number of colonies, with 70 CFU/sheet. Although it has only been used for half a month, it may be because it is used for a long time every day, and I like to take it to the toilet and even when cooking (the greasy environment is also a favorite of bacteria), and it has never been cleaned, so the total number of colonies ranks first in the mobile phone film list (but only 10 CFU more than sample 2).
Based on the collected usage data, the users of the mobile phone film samples this time all have more or less "bad habits" and "good habits", which makes the total number of colonies among them "comparable".

Looking at the mobile phone cases, the total colony count is quite shocking. The total colony counts of the three mobile phone cases are 1300 CFU/piece, 6200 CFU/piece and 8000 CFU/piece respectively.

These three mobile phone case samples are comparable. They were purchased a long time ago (two and a half or three and a half years), and their usage habits are similar (they are carried to the toilet), and the users do not have sweaty hands. The difference is the daily usage time and cleaning habits. Samples 4 and 5 are used for more than 8 hours a day. Sample 4's mobile phone case is yellow, but the total number of colonies is actually less than that of Sample 6, which is only used for less than 2 hours a day, which is really surprising.

Among the samples tested this time, Sample 6 mobile phone case ranked first in total colony count with a result of 8000 CFU/piece.

Past data

Among the daily items we collected before, the samples with the highest total number of colonies are as follows:

Pillow: 2400CFU/cm2

Yoga mat: 5600 CFU/cm2

Beauty egg: 80,000,000 CFU/mL

If we consider the size of the area, the phone case with the highest total number of colonies does not seem to be super dirty compared to other items...

However, if compared with mobile phone films, it is a different matter.

Judging from the results, the total number of colonies on the phone case is much higher than that on the phone film. What is even more surprising is that for the same phone (the sample 1 phone film and the sample 5 phone case are from the same phone), the phone case is also dirtier than the phone film.

why is that?

The testing engineer said that the surface of the mobile phone film is smooth and contains no nutrients, so bacteria cannot grow freely, so the total number of colonies detected is relatively small.

Mobile phone cases are made of different materials and styles, and often have textures on the surface. In addition, we often hold the phone case with our whole hand when playing with the phone, which makes it easier for the phone case to become dirty. Therefore, the total number of colonies detected is more than that of mobile phone films.

Remember to disinfect your phone regularly, don’t just take care of the phone screen protector!

This time, it took a certain amount of time to check and send the samples for testing, and some bacteria had died before testing, so the bacterial test data was less than expected.

However, the detected bacteria may be pathogenic bacteria or conditional pathogens, which may threaten health even in small quantities. For example, Escherichia coli, which is common in toilets, can easily cause diarrhea. Staphylococcus aureus, which is easily produced by food spoilage in hot weather, may cause suppurative inflammation...

Due to time and sample limitations, we are unable to help you detect specific types of bacteria this time. We will dig deeper when we have the chance. Please remember to pay more attention to our "old for new" campaign.

In daily life, many people do not pay much attention to the maintenance of mobile phones. Mobile phone films and mobile phone cases are not only rarely cleaned, but also rarely replaced. A film or a mobile phone case is often used for as long as the mobile phone is used.

We still have to pay attention to mobile phone films and mobile phone cases!

Professor V has compiled a “Mobile Phone Case + Mobile Phone Film Maintenance Guide” for everyone, come and check it out!