Have you cleaned your washing machine in the last month? If not, you're not alone.
Less than 20% of people follow manufacturers recommendations and run a maintenance wash once a month.
I promise you though, once you read about the bacteria lurking in your laundry, you will be much keener to clean your washing machine and join the minority that regularly clean their machines.
I was raised not to be scared of bacteria. My parents were very much of the opinion that exposure to some dirt was a good thing and that it would help build my immune system.
However, even with my tolerance for a bit of dirt, I was horrified to learn about the bacteria hiding in my washing machine. And doubly horrified to learn it can actually harbour more germs than a toilet!
Read this article to find out what types of bacteria you can find in the average washing machine and how you can get rid of them.
The Bacteria Thriving In Your Washing Machine
There are a number of different kinds of bacteria thriving in your washing machine. Thankfully, most are benign.
There are a few that are hazardous to our health, and scientists found these to include:
E.coli, Salmonella, Staphylococcus aureus, Pseudomonas aeruginosa and Klebsiella pneumoniae.
Doctor Charles Gerba is a world-renowned microbiologist. He has a long history of disgusting people with facts about the bacteria we come into contact with on a daily basis.
He has conducted several studies into the household chore of laundry and the associated bacteria. Here are just a couple of his findings:
Coliform Bacteria (Including E.Coli)
Escherichia coli, commonly known as E. coli is one of the nastier of the coliform bacteria.
It is found predominantly in faeces. In fact, the presence of E. coli is often used as confirmation of faecal contamination.
With this in mind, I have bad news for you.
When Dr Gerba swabbed 100 washing machines, he found that 60% had Coliform Bacteria present and 10% had strains of E. coli present.
That's right - the washing machine that you 'clean' your clothes in may well be contaminated with faecal matter. Yuck!
How E.coli Can Get Into Your Washing Machine
Just hows does this potentially deadly pathogen bacteria get inside our machines?
Without going too far into the dirty details, after using the toilet, no matter how thoroughly someone wipes, some faecal matter will transfer onto their underwear.
The underwear then transfers it onto the washing machine and the other garments in the wash with it.
Just when you thought it couldn't get worse, the E. coli can even lurk around long enough to contaminate the next batch of laundry.
Modern washers have a lot of plastic inside which provide welcoming homes for biofilms containing bacteria.
This is a particularly unpleasant thought if you're washing your tea towels or pillowcases after your clothes!
What Are The Symptoms & Effects of E.Coli?
Whilst many strains of E.Coli are relatively harmless, some can make you really sick.
Symptoms of an E.Coli infection include diarrhea, vomiting, fever, bloody stools, and painful stomach cramps.
In young children, an E. coli infection is the most common cause of acute kidney failure.
Salmonella
Salmonella is best known as a form of food poisoning.
However, it's possible to become infected by salmonella in other ways too, such as by having contact with someone who hasn't washed their hands properly, or by having contact with manure.
Salmonella is a tough bacterium, and was even found on clothes washed at 55 °c.
Like E. coli, being infected by salmonella is very unpleasant with diarrhoea, vomiting, stomach cramps, and sometimes a fever and the symptoms can last for up to a week.
Staphylococcus Aureus and S. Epidermidis
Staphylococcus aureus is better know as Staph Infection.
Staph is usually not that serious, causing skin irritation and boils. In serious cases it can develop into blood infections and even bone infections.
The other bad news is that Staphylococcus aureus and S. epidermidis can survive laundry programs at 50 °C.
This again highlights the dangers of people advising cold water washes.
For that, scientists have proven that you need temperatures in excess of 60 degrees.
Is The Problem Getting Worse?
There is speculation that the problem may have become worse in recent years.
The reasons behind this are our preference for washing at lower temperatures and using detergents that no longer contain bleach, such a bio laundry detergent.
Also, a lot of modern washing machines contain more plastics. This provides a really hospitable surface for biofilms and bacteria to grow on.
Some Manufacturers Are Failing Consumers
Some of the big-name manufacturers have released models with special "Anti-Bacterial" programs which are claimed to wash in excess of 60 ° C.
However, an investigation by Which magazine found that 8 out of 12 washing machines never actually reached the advertised 60 ° C. One only reached 43 ° C !
These is pretty damning evidence and certainly making matters worse.
The Dangerous Trend Of Cold Water Washes
It's true that millions of people around the world are using either cold water or very low temperatures to wash clothes.
But let's take a second to recap some of the important data in this article:
And perhaps the most important point:
Cold water can clean your clothes - but it can't disinfect them. For that you need a water temp of at least 60 ° C.
Laundry Detergent Choice
As well as monthly maintenance washes, manufacturers recommend that you use a detergent with a bleaching agent. This way it may be possible to wash at 40 °C and still kill germs.
However, this comes with a couple of caveats.
The first is that many people aren't using detergents that contain bleach.
And it's not really their fault. Washing detergents are designed to clean clothes and in some cases stop colours from fading. Not to disinfect clothes!
Bleaches are usually found in white washing powders. So if you're using a coloured powder or some form of liquid, chances are it doesn't have any bleach in it.
The second thing to be aware is how the bleaching agents actually work. The bleach is usually chlorine and peroxide based.
At lower temperatures, scientists have shown the bleach activity decreases and become largely ineffective. And if your washing in cold water, it becomes even more ineffective.
How To Wash Clothes Hygienically
If like me, all this talk of faecal matter and nasty bugs has got you feeling squeamish. I'm sure you'll want to ensure your washing machine and resulting laundry is as clean as possible.
Here are 6 tips for washing clothes hygienically.
1. Use A Detergent With Bleach
Finding a detergent with bleach is key to protecting against bacteria, especially if like most people you're washing at 40 °C.
Be sure to read the label or description for the ingredients.
Some products that do use bleach are "Tide Plus Bleach", Ecover and Ariel Automatic Powder Original.
Of course, you do need to be careful with colours. Washing colours with detergents which contain sodium hypochlorite (NaOCl) can make their colours run.
However, there are some detergents that use hydrogen peroxide (H2O2) based bleaches. This are much better for keeping your clothes the right colours!
2. Wash Your Undies Separately
Ok, so this just sounds like a chore on top of another chore, but washing your underwear in a separate load makes sense. Especially as we now know that the faecal matter can transfer onto other items in the washing machine drum.
Make sure you use a high temperature and bleach-based detergent to exterminate all the nasties.
3. Clean Your Washing Machine Regularly
I'm confident that by now, you don't need any more convincing on the importance of cleaning your washing machine.
For this, you can use cleaning bleach, white vinegar and some baking soda.
We have a page with tips for cleaning the detergent drawer, drum, seals and filter.
4. Run a Maintenance Cycle Monthly
Some of the latest washing machines have self-cleaning programs which you need to run monthly.
If yours doesn't you can run a high-temperature cycle without any clothes inside. Yes, it does sound a waste of energy, but this will reduce the health risks for you and your family.
5. Wear Gloves Or Wash Your Hands
After you handle your laundry, for example by taking it outside to dry, make sure you wash your hands.
Dr Gerba even recommends wearing gloves! His reasoning? Often after handling the laundry, we will prepare food or spread the contamination to elsewhere in our home.
6. Dry Clothes Outside
Drying outside on a washing line is better for your energy bills and overall health. It also has the added benefit that the sun can help kill bacteria.
The sun acts as a natural disinfectant, so think twice about using the dryer next time.
I hope I've not grossed you out too much and that you've found some way to enjoy this article.
What do you think? Is a bit of bacteria good for us? Or will you be sorting your laundry wearing elbow-high gloves and buckets of bleach?
Let us know in the comments below.
Meanwhile, here is the full info-graphic if you would like to share!
Really informative. Thank you
Do you know if original tide powder contains a bleaching agent? If so would it kill klebsiella pneumoniae bacteria and at what temperature? Thank you!
Hi,
AFAIK Tide Original contains Sodium Carbonate Peroxide, which is a bleaching agent.
You can find a full list of ingredients on their website:
https://tide.com/en-us/ingredients/tide-detergent-ingredients-a-to-z
(Great to see Tide having this level of transparency btw)
Regarding temperature, this scientific survey recommended 60 degrees (with tumble dryer) or 70 degrees without.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4229498/
Thanks for reading and commenting!
this was very informative. thank you
Cold water does not cause household bleach to become ineffective. Hot water can but usually washers don’t get hot enough or run long enough for that to happen.
.
I take the point, but bleach is not “As effective” as with warm water. This interesting article recommends using hot water when washing highly-soiled clothing:
https://eu.usatoday.com/story/news/health/2019/09/30/drug-resistant-bacteria-found-hospital-washing-machine-study-says/3817028002/
As you also say, the modern “efficient” machines don’t get hot enough to kill all bacteria. But usually in a healthy household the germs that are left wouldn’t cause problems.
Thanks for the comments!
Since washing machines do not reach the temperatures specified on their settings, eg: a 60 degree C wash only reaches 50 or so degrees C. This may suggest why/how staph can survive on a 50 degree C wash and Salmonella survives 55 degree C wash, as the washing machine never reaches that temperature. I have tested my machine and the 95 degree C wash only ever reaches 74 degrees C maximum, and the 60 degree wash reaches 55 degree C maximum. It is not consistent either, with the “95” wash ranging between 70 and 74 degrees C, so never the same temperature consecutively.
This is of course disappointing that washing machine manufacturers get away with this and leads people to believe that when they are washing their laundry, that their 60 Degree C setting on their machine, is sufficient at ridding bacteria, when in reality, it isn’t reaching those temperatures, thus not ridding the bacteria concerned. False advertising maybe?
Since my machine does not have an actual 60 degrees C temperature, I am left with 50 odd degrees C (on the 60C setting) or 70 odd degrees C (on the 95C setting). So as bacteria can survive the 50-55C temperatures, my question is: Is 70 degrees C hot enough to eliminate bacteria on laundry, without using bleach based detergents?
Yes, I agree. The same can be said of “1600rpm spin speeds” which many laundry programmes do not use.
Regarding your question about not using bleach-based detergents, 70 degrees C is hot enough to kill most bacteria and viruses.
There is a table at the bottom of this page from the World Heath Organization shows the ones that still survive (like Hepatitis A)
https://www.who.int/water_sanitation_health/dwq/Boiling_water_01_15.pdf?ua=1
Thank you kindly for that table/link, it is very useful and informative.
It is good to know that 70 degrees C is enough to kill off most bacteria.
The time of course is a contributing factor, since I know my machine only reaches 70-74 degrees C on the 95 setting, I also know that it maintains this temperature for about 10 – 15 mins. So also good to see from the table you provided, that 70 degrees C for a few seconds – couple of minutes is long enough to kill bacteria. Gives me a little faith that the 10 mins at 70 degrees that my machine does, is sufficient at ridding bacteria.
I have also discovered that almost all clothes can withstand a 70 degrees C wash, despite their labels saying to wash at 40 or 30 or some even hand wash. Of the hundreds of items I have washed at 70 degrees C, only a handful have been ruined (mainly swimwear and sports bras), to the point of them being discoloured or faded. Thus, still physically wearable, if you don’t mind the colour change.
Thanks again for your reply and the table of info.
Though I do worry about clothing that cannot be put on hot/70 degree c washes. What would be sufficient for ridding bacteria on clothing that can only be washed at 40 degrees c?
Thank you kindly for that table/link, it is very useful and informative.
It is good to know that 70 degrees C is enough to kill off most bacteria.
The time of course is a contributing factor, since I know my machine only reaches 70-74 degrees C on the 95 setting, I also know that it maintains this temperature for about 10 – 15 mins. So also good to see from the table you provided, that 70 degrees C for a few seconds – couple of minutes, is long enough to kill bacteria. Gives me a little faith that the 10 mins at 70 degrees that my machine does, is sufficient at ridding bacteria.
I have also discovered that almost all clothes can withstand a 70 degrees C wash, despite their labels saying to wash at 40 or 30 or some even hand wash. Of the hundreds of items I have washed at 70 degrees C, only a handful have been ruined (mainly swimwear and sports bras), to the point of them being discoloured or faded. Thus, still physically wearable, if you don’t mind the colour change.
Thanks again for your reply and the table of info.