Millions of bacteria could be lurking in your kitchen, on sponges, chopping boards and in storage containers, food safety experts have warned.
According to a leading public health specialist, millions of Brits are risking potentially deadly food poisoning by failing to replace a range of utensils often enough.
Many of the 2.4million cases of food poisoning a year can be attributed to contaminated kitchen gear, the Food Standards Agency (FSA).
In fact, 40 per cent of all outbreaks in Europe occur.
Here, food safety expert Sylvia Anderson — who conducts audits for some of the UK’s biggest restaurant chains and hotels — reveals how surprisingly often we should be changing our cooking and cleaning tools.
Sponges: replace every fortnight
Sponges can harbour as much as 10 million bacteria per square inch, including diarrhoea-causing bugs E.coli and Salmonella, common bacteria often found on raw meat that causes food poisoning — and can be deadly to those vulnerable
The moist environment of a sponge makes them notoriously one of the dirtiest items in the kitchen, Ms Anderson told MailOnline.
She claims they can harbour as much as 10 million bacteria per square inch, including diarrhoea-causing bugs E.coli and Salmonella, common bacteria often found on raw meat that causes food poisoning — and can be deadly to those vulnerable.
‘Simply wiping surfaces can spread these germs rather than clean them,’ Ms Anderson said.
She added: ‘Bacteria from sponges can transfer to dishes, counters, and hands, leading to foodborne illnesses or infections.
‘Since they retain moisture, sponges are ideal for bacteria growth, which can contaminate kitchen surfaces.’
Due to their porous structure and ability to soak up water, they are ideal incubators for microorganisms.
There could be as many as 45 billion bacteria per square centimeter of sponge, according to a 2017 study published in Scientific Reports. Researchers found 362 different species living on used kitchen sponges.
To keep your kitchen clean, Ms Anderson recommends sanitising your sponges daily for one minute by soaking them in boiling water or bleach solution. She also urges people to replace them every two weeks.
Scrubbing brushes: wash every week and replace every six months
Lower levels of bacteria was found on scrubbing brushes than on sponges, according to a separate 2022 study.
It also revealed that salmonella died more rapidly on brushes, suggesting that it may be more hygienic to wash your dishes with brushes rather than sponges.
‘Scrubbing brushes should be cleaned once a week by soaking them in a bleach solution and replacing them if the bristles begin to fray,’ Ms Anderson said.
Lower levels of bacteria was found on scrubbing brushes than on sponges, according to a separate 2022 study
‘They are breeding grounds for bacteria like E. coli if not cleaned regularly. They come into direct contact with dishes and surfaces, making it easy for germs to spread,’ she added.
That’s why she urges people to wash their kitchen brushes every week and replace them every six months.
Tea towels: wash every two days
Tea towels and cloths are another big cause of cross-contamination in the kitchen.
That’s because they can be used for a wide variety of purposes, such as mopping up spills, wiping surfaces, drying plates and wiping hands, the FSA warns.
Instead, the FSA recommends we use different cloths for specific tasks and wash them regularly.
‘A damp tea towel is an ideal environment for bacteria, particularly if it’s been in contact with raw food residues,’ Ms Anderson said.
She warns damp towels can carry Staphylococcus aureus, which can cause skin infections or stomach upsets including vomiting and diarrhea if transferred to food or utensils.
‘It’s best to rotate through several towels and wash them after a day or two of use, or immediately after wiping down spills from raw meat,’ she added.
Chopping boards: use wooden ones — and replace every year
You may be safer opting for a wooden chopping board over a plastic one, research suggests
Chopping boards are rife with harmful bacteria, and are perhaps the riskiest kitchen utensil for contracting an infection.
‘Cross-contamination is the biggest concern. If you use the same chopping board for raw meat and vegetables without washing it, bacteria like Campylobacter or E.coli can transfer to ready-to-eat foods, leading to serious illness,’ Ms Anderson said.
One 2023 FSA study found about half of household chopping boards contain bacteria.
Researchers tested 25 chopping boards for the presence of key foodborne disease-causing bacteria and bugs that originate from the human gut or skin.
Gut bacteria was found to be present on 44 per cent and skin bacteria was found on 52 per cent of the chopping boards.
But you may be safer opting for a wooden chopping board over a plastic one, the study suggested.
Gut microbiota were present on 66.67 per cent of plastic and 20 per cent of wooden chopping boards. Skin microbiota were present on 50 per cent of plastic and 70 per cent of wooden chopping boards.
‘Wooden boards are naturally antimicrobial but need regular oiling to prevent cracking. Plastic boards, while dishwasher safe, can develop deep cuts that trap bacteria, making thorough cleaning difficult,’ Ms Anderson warns.
But not only should we be washing our chopping boards after every use, we should also consider replacing wooden boards every year to 18 months or as soon as deep grooves appear if it is plastic.
Kitchen knives: swap at the first sign of rust
If knives used to cut meat are left unwashed for too long, bacteria can dry and stick to the blade
It’s common practice to wash knifes used to cut raw meat, fish, or poultry immediately after use. And for good reason.
If left unwashed for too long, bacteria can dry and stick to the blade, Ms Anderson warns.
In a 2015 study funded by the U.S. Food and Drug Administration, University of Georgia researchers found that continued use of knives and graters can pass on bacteria.
This can happen when produce containing bacteria is cut and the same knife is used again contaminating other produce.
It’s thought the bacteria latches on to the utensils commonly found in consumers’ homes and spreads to the next item.
But it’s not just unwashed knives that can cause cross-contamination, letting them get rusty can also put you at risk of food poisoning.
That’s because over time knives can develop rust spots or dull edges, which are harder to clean thoroughly and can harbour germs in crevices, Ms Anderson explains.
To prevent this from happening, she recommends making sure your knives are dried thoroughly before storing to prevent rust.
Not only should they be washed after every use, they need to be sharpened or replaced when dull or rusted.
Plastic storage containers: watch out for stains or cracks
By using old, scratched plastic containers you’re not just risking food poisoning, but also chemicals leaching into your food
Worn, scratched or stained plastic containers could be covered in bacteria and should be replaced.
‘The damage can harbour bacteria, and over time, these containers can absorb food odours and stains,’ Ms Anderson said.
Containers that have not be cleaned properly or that have been damaged can harbour mould, yeast, and bacteria, leading to contamination of your food, she added.
But by using old, scratched plastic containers you’re not just risking food poisoning, but also chemicals leaching into your food.
‘Chemicals from worn-out plastic containers can also leach into food, especially when heated, which may have potential long-term health effects,’ Ms Anderson said.
‘Microwaving food in old plastic containers may cause harmful chemicals like BPA to leach into food, though many are BPA-free today.
‘Still, it’s crucial to wash them thoroughly after each use to prevent contamination.’
That’s why she urges people to wash them after every use and replace when it gets stained, cracked, or showing signs of wear.
