Explainer: How dangerous is formaldehyde, a sour-smelling chemical used in furniture, and what should homebuyers know about it?

SINGAPORE, July 13 — When a family moved into their newly renovated condominium unit at Normanton Park in Queenstown in March, they reportedly began experiencing symptoms such as dry eyes and sore throats.

A medical check-up revealed they could be suffering from formaldehyde poisoning.

According to Chinese-language daily Lianhe Zaobao on June 14, they had allegedly been exposed to the colourless chemical commonly found in furniture. It has a distinctive smell similar to vinegar or pickles.

Tests at their home revealed that about 31 pieces of furniture exceeded the recommended formaldehyde level of below 0.08ppm (parts per million).

Lianhe Zaobao reported that the formaldehyde concentration in a drawer in one room was alarmingly high, reaching 4.8ppm — 60 times the acceptable limit.

More people here are also seeking professional help to remove formaldehyde from their home furniture, reported CNA on Thursday (July 11), with some treatment firms saying they are handling up to 70 per cent more cases as compared to last year.

Yesterday, the National Environment Agency (NEA) told TODAY that it is closely monitoring feedback regarding formaldehyde levels in homes arising from renovation works.

So what is formaldehyde, how can it adversely affect human health, and what should new homeowners do to protect themselves?

What is formaldehyde?

Despite its well-documented dangers, formaldehyde remains a staple in various industries mainly because it is an effective preservative.

According to the Agency for Toxic Substances and Disease Registry in the United States, formaldehyde is among the 25 most widely produced chemicals globally. It is extensively used in the manufacture of plastics, resins and urea-formaldehyde foam insulation.

Around the house, it is commonly found in plywood, particleboards and medium-density fiberboards. Household products such as glues, paints and coatings, lacquers and finishes also contain formaldehyde in varying concentrations.

These materials are highly favoured in the construction and furniture industries due to their strength, durability and cost-efficiency.

The textile industry also heavily relies on formaldehyde. It is instrumental in producing wrinkle-resistant and durable fabrics, which are highly sought after by consumers.

Moreover, formaldehyde helps bind dyes to fabrics, producing vibrant, long-lasting colours.

In a recent move, Minister for Sustainability and the Environment Grace Fu said Singapore will prohibit the use of formaldehyde in interior building paints starting from 2026.

“Prolonged exposure to formaldehyde can lead to negative health effects, such as respiratory discomfort and an increased risk of certain cancers,” Fu told Parliament in March.

The new regulation mandates that formaldehyde content in paints not exceed 0.01 per cent of the paint’s weight. Manufacturers are required to submit compliance test reports from accredited laboratories.

NEA’s spokesperson told TODAY yesterday that it is reviewing international best practices, guidelines and regulatory requirements before considering potential new controls.

Symptoms of exposure

People are exposed to formaldehyde both at work and at home, with the highest levels found in workplaces where formaldehyde is used or produced.

Exposure can pose serious health risks, causing irritation of the eyes, nose and throat, even at low levels.

Dr Steve Yang, a respiratory physician at Mount Elizabeth Hospital, said that fairly low concentrations of formaldehyde can quickly cause nose and throat irritation, manifesting as cough, chest pain, shortness of breath and wheezing.

“These symptoms can develop immediately or within three to four hours after exposure and can last from hours to days.”

Dr Yang added that higher exposure levels can lead to significant lower respiratory tract inflammation, affecting the trachea and bronchi, and causing fluid accumulation in the lungs. Prolonged exposure, lasting 12 hours or more, can result in severe pulmonary injury.

Another respiratory physician, Dr Chew Huck Chin, said prolonged exposure to formaldehyde, classified as a human carcinogen, can also increase the risk of cancers, especially nasopharyngeal cancer and leukaemia.

Both doctors acknowledged that it can be challenging to distinguish between irritations caused by formaldehyde and those caused by common household allergens, as the symptoms are usually the same.

But there are several key indicators:

• Allergens are usually found in exposure to bedding, carpets, soft toys and fabric. Formaldehyde is generally found in cabinets and particle boards, which are uncommon sources of allergens
• Timing and environment, as symptoms usually worsen in newly renovated or poorly ventilated areas
• Blood and urine tests can detect formaldehyde exposure, but the diagnosis often relies on symptom patterns and environmental assessment

Can be inhaled, absorbed in skin

Inhalation is the primary route of formaldehyde exposure, occurring in environments where formaldehyde-containing products are used or during combustion processes.

Industries using formaldehyde in materials like textiles, plastics or resins face heightened risks. Similarly, homes with poor ventilation, particularly those containing formaldehyde-emitting products, can expose residents to harmful chemical levels.

Ingestion of formaldehyde, though less common, can also lead to poisoning, according to the Centre for Radiation, Chemical and Environmental Hazards in the United Kingdom.

This can occur accidentally, especially in cases where formaldehyde-containing solutions are ingested or when food and water become contaminated.

Skin contact is another possible route of exposure. Direct contact with formaldehyde solutions can cause skin irritation and enable absorption through the skin.

Additionally, formaldehyde vapours or solutions can irritate the eyes and mucous membranes, leading to discomfort and potential damage.

What should homeowners do?

Managing formaldehyde in indoor spaces is crucial to maintaining a healthy environment.

To reduce formaldehyde concentrations, the NEA spokesperson stressed the importance of ensuring proper ventilation, especially during and immediately after introducing products that contain formaldehyde.

Dr Chew said using air purifiers equipped with formaldehyde filters to clean the air helps, too.

“Opt for low-emission materials and furnishings to minimise formaldehyde emissions. Additionally, maintain moderate humidity levels to help reduce the release of formaldehyde from indoor sources.”

Those concerned about formaldehyde exposure or experience related symptoms should seek medical attention immediately.

For those looking to accurately measure formaldehyde levels at home, Dr Yang said this requires a professional indoor air quality consultant who uses advanced testing methods that provide precise and reliable results, unlike consumer-available kits.

The downside is that hiring these professionals can be costly.

“There are self-test kits available, but the results might not be comparable with tests done by qualified professionals, as some kits react to a lot of common gases, not just formaldehyde,” said Dr Yang.

“But one thing to note, if you can smell it, it is there. Don’t waste time and money testing for it.” — TODAY