How washing machines can put your family's health at risk
Low temperatures and mixed loads are spreading dangerous bugsBy Fiona Duffy
The pasta stains might have disappeared — but are your freshly laundered clothes really clean? In our desire to be greener, as well as softer on clothes, many of us are lowering the temperature of our washes.
The maker of Ariel Gel is encouraging consumers to wash at 15c rather than 40c in order to halve energy costs. But experts are concerned our bid to save the planet — and money — will affect our health.
For while we associate laundry with cleanliness, some estimates say the average washing machine load contains 100 million E.coli at any one time.
Professor Sally Bloomfield, of the London School of Hygiene and Tropical Medicine, wants a campaign to educate consumers in laundry hygiene. ‘We need to launder clothing in a way that renders them not just visually clean, but hygienically clean — the two are not the same,’ she says.
Her concerns are backed by a German study on clothes contaminated with Staphylococcus aureus, linked to skin and urinary tract infections, as well as pneumonia. Researchers found the only way to eradicate the bacterium was with temperatures of 40c and above combined with a detergent containing bleach.
‘If you work with food and put your uniform in with the rest of the family’s dirty laundry, including dirty underwear, it could become infected with e.coli or salmonella — or whatever else is on those clothes,’ says Dr Lisa Ackerley, a consultant in environmental hygiene.
‘In winter, the norovirus (the vomiting bug) could easily spread through a family via the washing machine if you’re not using a high enough temperature wash.’
While most people are resilient to such infections, for those with reduced immunity, such as the elderly and patients recently discharged from hospital, this can cause real problems.
Meanwhile, allergy experts are concerned about the impact of low-temperature washing, as studies show washing at 30c or 40c kills just 6 per cent of house dust mites, compared with 100 per cent at 60c.
‘The old-fashioned way of washing clothes was to boil them at 100c.’ says John Oxford, professor of virology at St Barts and the London School of Medicine and Dentistry and chair of the Global Hygiene Council.
‘These days, people are lowering temperatures to 40c or even lower. To be sure of getting rid of faecal bugs, you need to get the temperature back up to 60c.’
Even choosing the right detergent isn’t as straightforward as it might seem. There are two types of detergent: non-biological, which contains bleach to clean and disinfect, and biological detergents, which rely on enzymes (naturally occurring proteins harvested from micro-organisms) to digest and rinse away proteins and compounds that make up dirt. Manufacturers say enzymes are effective at lower temperatures and less harsh on fabrics.
Many consumers believe biological detergents are harsher on sensitive skin, but a study published in the British Journal Of Dermatology found little evidence for this.
As for powder versus liquid detergents, the latter tend not to contain bleach. Powder has been used successfully for decades, says Andy Trigg, washing machine engineer and founder of White Goods Help. ‘If liquid was definitely better than powder, powder would have disappeared by now, but it hasn’t,’ he says.
In terms of temperature, the Hygiene Council recommends that all clothes, linens and other fabrics should be laundered at a high temperature — i.e., 60c — to be sure bacteria, viruses and dust mites have been destroyed.
It also says if lower temperatures are used, then a laundry disinfectant should be added — particularly for the laundry of small children or other contaminated items.
disinfectant liquid to a regular detergent (see bottles for instructions).
Other products that claim to leave clothes hygienically clean at lower temperatures include Milton Antibacterial fabric solution, Eradicil laundry sanitiser and Halo detergent. Professor Bloomfield says if anyone in the household is ill or has poor immunity, it’s important to wash at 60c.
Many of us think nothing of throwing our underwear into the machine with the rest of the laundry. In fact, there’s a high risk your undies will harbour bacteria and they should be kept separate from low-risk items, such as skirts and shirts.
Instead, your underwear should have a high-temperature machine wash to itself or be cleaned with towels and sheets, agree experts.
A study by Hygiene Audit Systems found living bacteria, such as Staphylococcus aureus and E.coli, on 83 per cent of laundered underwear samples.
Of the samples tested, 89 per cent had been washed at temperatures of 40c or lower. Dr Lisa Ackerley, who carried out the study, says: ‘Washing underwear separately and at a high temperature is even more important if the wearer is ill or suffering from an infection,’ she says. ‘Some organisms secreted by the body when a person is ill are infectious even in low doses.’
Bathroom and kitchen-related items should each have their own hot wash cycle, says Dr Ackerley.
‘Babies have a lower immune system and are more susceptible to bacterial or fungal infections, which could easily be transferred during a low-temperature wash.’
The latest green alternative to detergent is ‘laundry balls’, which contain pellets of minerals. But do they clean clothes hygienically?
Simeon Van Der Molen, managing director of Ecozone, which produces Ecoballs, says: ‘They are a natural, alternative product for everyday, lightly-soiled, clothing.
‘Most of their ingredients are similar to what you will find in a laundry detergent, but without the harsher chemical ones. But the results are far below what you’d get with something like Persil because of the enzymes and the technology that has gone into that product.
‘If someone is ill in the house, we would say, regardless of the product, do all washes at 60c — this will kill most bacteria.’
Experts also urge people to clean the washing machine, amid concern that low temperatures and detergents without bleach are taking their toll on the machines.
Dr Ackerley explains: ‘A washing machine that is only ever run at low temperatures will be heaving with mould and bacteria. Most manufacturers recommend carry out a weekly or monthly very hot wash to clean the machine out.
‘I regularly wash my white towels at 95c to give the machine a good clean and reduce the bacteria load.’
Andy Trigg adds that ‘dirty machines’ have only become a problem since the launch of liquid detergents in the mid-Nineties.
‘Liquid detergent doesn’t contain bleaching agents,’ he says. ‘And it is these bleaching agents that help keep the washing machine free from bacteria and black mould. A maintenance wash is particularly important if you mostly use low-temperature washes and or liquid, or colour-friendly, detergent.
‘Once a month, put the washing machine on the hottest wash with a bleach-based detergent. Cleaning the detergent drawer and the rubber ring also reduce problems.’
The Hygiene Council adds: ‘It is important that all household cloths are cleaned on a regular basis by either disinfecting, boiling or placing them in a hot wash in the washing machine at a minimum temperature of 60c and then ensuring they are dried properly after each use.’