Though not visible to the naked eye, you could probably spot formaldehyde by its smell. It is present in just about all of our homes and workplaces – the newer the building, the higher the probability new furniture and flooring with manufactured wood were used. With around 21 million tons of annual production (as of 2019), formaldehyde is one of the most widely produced organic chemicals.
What is Formaldehyde?
Formaldehyde, also called formalin as an aqueous solution, is a colorless and very water-soluble gas. The odor of formaldehyde is pungent, so that humans and animals perceive it even in small quantities. Formaldehyde in indoor air is extremely reactive, interacting with proteins, DNA, and RNA, and is classified as an air pollutant by many authorities.
Formaldehyde is suspected of being carcinogenic and has been classified as that by the International Agency for Research on Cancer (IARC). Inhalation of the substance can cause irritations of nose, mouth and throat. Inhalation, ingestion or skin contact with this substance can lead to serious reactions, which will be discussed in more detail later.
Where can Formaldehyde be found?
Formaldehyde is formed during the oxidation of hydrocarbons and as a direct emission during combustion processes. It is therefore present, for example, in exhaust gases from motor vehicles. The amount emitted varies depending on the fuel used. However, formaldehyde is much more frequently found in indoor air, where it is emitted from anthropogenic (man-made) sources. Especially indoors, the gas endangers our health. How harmful formaldehyde in indoor air is for each individual depends on its concentration and the individual constitution.
What are sources of formaldehyde indoors?
Formaldehyde is still produced in large quantities and is present in products we use daily. Due to its numerous applications, it occurs relatively frequently in building materials and materials for interior decoration. By far the largest source of exposure is textiles and wood-based materials that have been glued with formaldehyde resins. In addition to wood-based materials, insulating foams, glass wool, textile floor coverings, varnishes, wooden toys, paints and cosmetics also contain formaldehyde. Combustion processes such as smoking, heating, cooking, candle or incense burning can also release significant amounts of the harmful gas. The release of the gas is elevated by higher temperatures and humidity. Even treated special papers (with increased waterproof strength) or heated raw wood in saunas can emit formaldehyde into the air. The easiest way to reduce exposure is to stop using substances containing formaldehyde at home or in work environments.
What effects does formaldehyde have on the human body?
When formaldehyde is present indoors, people absorb it through breathing and through their skin. The pollutant can also enter the body through the gastrointestinal tract, for example when children put contaminated toys in their mouths. Formaldehyde has a direct effect on tissues exposed to the air. The mucous membranes in the mouth, nose and throat absorb the gas particularly quickly. However, only a small portion reaches the deep bronchial tubes. Short-term exposure causes irritation of the eyes and respiratory tract with coughing fits, lacrimation, and headaches and earaches. Some sufferers complain of nausea and vomiting, nervousness, sleep disturbances, and susceptibility to stress. Skin contact can also lead to formaldehyde allergy.
Furthermore, the substance is suspected of causing asthma. With increasing concentration of formaldehyde in the room air, the complaints intensify.
If the respiratory tract is constantly irritated, chronic symptoms develop, increasing susceptibility to allergies such as pollen and mold. Those affected also complain of concentration disorders, inner restlessness, nausea, diarrhea with vomiting, and psychosomatic impairments. Long-term damage to the liver, lungs and kidneys has also been observed.
Despite its hazardous effect on health, this carbonyl compound is still present in various everyday products. And its harmful effect begins below the odor threshold.
What are acceptable levels of formaldehyde?
When you talk about the amounts or concentrations of such toxins as formaldehyde in the air, you express it in "ppm". This stands for "parts per million", and 1 ppm corresponds to 1.2 milligrams per cubic meter. The acidic pungent odor can be perceived at 0.5 ppm to 0.125 ppm, but formaldehyde can cause irritation of the eyes even at 0.01 ppm, well below the odor threshold. From 0.08 ppm, irritation of the nose is added, and from 0.5, irritation of the throat. For practical comparison: in an unventilated room of 30 m³ (1,059 ft3) size, smoking 3 cigarettes is enough to pollute the air with 0.5 ppm formaldehyde.
The Short-Term Exposure Limit (STEL) for formaldehyde is 2 ppm in many countries, meaning the average exposure to a person during any 15-minute period must not exceed 2 ppm. Exposure at or above the STEL triggers special requirements. The Action Level - the trigger for increased industrial hygiene monitoring and initiation of worker medical surveillance - for formaldehyde is 0.5 ppm averaged over an 8-hour period.
The World Health Organization (WHO) has developed a guideline for formaldehyde in non-occupational settings at 100 ppb (parts per billion) (0.1 mg/m3) for 30 minutes.
How do I know about my formaldehyde exposure level?
In the recent past, a large number of studies and investigations have been published on the hazards of formaldehyde, especially in closed indoor spaces, where we spend more than 90% of our time. Due to the fact that formaldehyde is still present in many everyday products or can be generated by their handling, it is essential to identify and eliminate possible sources of risk. The only way to identify potential hazards and understand exposure levels is through continuous monitoring with instrumentation. In addition to formaldehyde, the AirAssure™ IAQ Monitor (model 8144-4) measures other IAQ parameters such as CO, tVOCs, CO2, particulate matter, barometric pressure, temperature and relative humidity. That makes it ideal for rooms with pressed wood building materials or furniture, cigarette or fuel-based smoke, and other textiles or glue.
TSI Link™ Solutions is the cloud-based software that connects with our indoor and outdoor air quality monitors allowing access to remotely track IAQ conditions and visualize data in real-time through a custom dashboard, along with multiple integration options.
We are happy to help you with any questions you may have about formaldehyde and IAQ. Contact our IAQ solutions consultants today.