WHEN the haze rolls in, some social media users say the laundry should come indoors too.
A Threads post warning against hanging clothes outside once the Air Pollutant Index (API) crosses 100 drew a flood of comments from people who said their skin itched after wearing clothes dried in the open.
So, can clothes dried outdoors during the haze irritate your skin?
Verdict:
TRUE
Yes, they may, particularly for babies, children and adults with eczema or sensitive skin, although experts say there is limited evidence that such clothes cause skin disease.
Pollutant residue on clothes may cause irritation such as itchiness or redness, especially in people with eczema or sensitive skin, consultant paediatrician Dr Mohd Zaqrul Razmal Mohd Podzi told fact-checking portal MyCheck.my.
The user behind the viral post described the advice as a precaution rather than an official rule, saying fine particles in the air, including PM2.5, could stick to clothes hung outside.
According to the Environment Department, API readings between 101 and 200 are categorised as unhealthy, a level of pollution that can affect the health of high-risk groups.
Retired Health Ministry director Datuk Dr Zainal Ariffin Omar advised the public to check the API before heading out, as reported by The Star on Oct 2.
Activity is generally acceptable below 100, strenuous activity should be reduced between 101 and 200, while outdoor exertion should be avoided above 200, he said.
Scientific studies support the possibility of haze particles settling on fabric.
A 2004 study by Mhd Radzi Abas and colleagues, published in Atmospheric Environment, found that airborne particles collected during a haze episode in Kuala Lumpur contained organic compounds linked to biomass burning and fossil fuel combustion.
A separate 2023 study by Jhang and colleagues in Building and Environment found that airborne particles could settle on clothing, with fabric type, surface roughness and air speed affecting how many particles accumulated.
Taken together, the studies suggest that clothes dried outdoors during the haze may collect pollutant particles, with the amount depending on factors such as pollution levels, surroundings and fabric type.
The Health Ministry's Info Sihat portal lists itchy skin as one of the symptoms people may experience during the haze, while Universiti Malaysia Sabah public health specialist Assoc Prof Dr Syed Sharizman Syed Abdul Rahim has warned that haze carries a risk of skin problems such as itching and acne, as reported by Bernama on Sept 8.
Dr Mohd Zaqrul Razmal, who is also chief executive officer of SALAM Senawang Specialist Hospital, said particular attention should be paid to babies, children and adults with eczema or sensitive skin.
"When polluted air comes into contact with clothes, some particles can settle on the surface or become trapped in the fabric fibres. The amount varies according to the level of pollution, the duration of exposure and the type of fabric," he said.
PM2.5 refers to fine particles measuring 2.5 micrometres or smaller, which can come from sources such as forest fires and vehicle exhaust.
However, Dr Mohd Zaqrul Razmal stressed that finding particles on clothes did not mean the clothes would cause skin disease.
Health risks depend on the level of exposure, the nature of the pollutants and the individual's health, while the main concern with PM2.5 is inhalation because the tiny particles can travel deep into the lungs.
Haze also contains gaseous pollutants, but gases and particles behave differently and cannot be assumed to cling to fabric in the same way, he said.
Specific scientific evidence linking clothes dried during the haze to skin disease remains limited.
"Contact between pollutants and the skin does not necessarily mean those substances penetrate the skin or cause disease," Dr Mohd Zaqrul Razmal said.
Research has, however, found links between polluted air and skin problems.
A 2021 study published in JAMA Dermatology examined dermatology clinic visits in San Francisco after smoke from California's Camp Fire blanketed the city in 2018.
Weekly clinic visits for atopic dermatitis, the most common form of eczema, were 1.49 times higher among children and 1.15 times higher among adults during the fire weeks compared with the same periods in years without major wildfires. Children's clinic visits for itch were 1.82 times higher.
Dr Maria Wei, a dermatology professor at the University of California, San Francisco, said in a statement by the American Academy of Dermatology that short-term exposure to wildfire air pollution could affect the skin and trigger flare-ups of certain skin disorders.
Closer to home, a 2024 Scientific Reports study of outpatient consultations for atopic dermatitis at Singapore's National Skin Centre found the likelihood of a visit was about 10% higher when PM2.5 levels were elevated.
Neither study examined laundry, however, meaning they show that polluted air may aggravate sensitive skin rather than prove that clothes dried outdoors are responsible.
For families with babies, children with eczema or anyone with sensitive skin, Dr Mohd Zaqrul Razmal recommended using a tumble dryer where possible or running an extra washing machine spin cycle to remove more water before drying clothes indoors.
Clothes should be spaced out and a fan or dehumidifier can be used to speed up drying. Keeping hazy air out and controlling indoor humidity can also help ensure clothes are completely dry before being worn or stored.
Clothes that are dusty or smell strongly of smoke should be washed again, he said.
Until the API drops out of the unhealthy range, drying clothes indoors in a well-ventilated room is a sensible precaution.
Sources:
2. https://www.thestar.com.my/
3. https://bernama.com/bm/am/
4. https://jamanetwork.com/
5. https://pmc.ncbi.nlm.nih.gov/
6. https://www.aad.org/news/
