FORMALDEHYDE and CHEMICAL SENSITIVITY*
Formaldehyde is a simple organic chemical widely used in our Western Society. It is volatile – the volatile nature causes it to be a gas at room temperature.
There are biological and medical uses. For example, formaldehyde is used as a disinfectant, a preservative in vaccines, to ‘fix’ tissues for pathological studies and as an embalming agent. Its use in industry ranges from the making of plywood or carpets to toothpaste and other personal care products. Details of the many products containing formaldehyde are set out below.
Health Effects of Formaldehyde.
Formaldehyde is one of the most troublesome of all the chemicals to which we are regularly exposed. Such exposure can bring on the whole spectrum of symptoms and disorders that can be caused by chemical intolerance or chemical sensitivity. It can affect every organ in the body. The symptoms that can result from exposure in a chemically sensitive person have been set out in detail in ‘How to Stop Feeling So Awful’, chapter 7 ‘The Symptoms of Ecological Illness’ (pages 63-70).
The common symptoms of formaldehyde exposure are respiratory, skin and gastric aliments, as well as fatigue, migraine and headache, muscle and joint aches and pains. Less common, but perhaps more disturbing, symptoms include poor memory, reduced concentration and alertness, depression, apathy and insomnia. However any organ in the body can be affected and cause symptoms. These are all in addition to the acute effects of high levels of exposure (poisoning).
High levels of formaldehyde irritate the eyes and throat. The irritation of the eyes experienced in smog is due to the presence of formaldehyde. Higher levels can cause throat spasms and a build-up of fluid in the lungs, leading to death.
Drinking formaldehyde solutions, giving a very high exposure, is potentially lethal. Formaldehyde is converted to formic acid in the body, leading to a rise in blood acidity (acidosis), causing rapid, shallow breathing, blurred vision or complete blindness, hypothermia and, in the most severe cases, coma and death. People who have ingested formaldehyde require immediate medical attention.
Contact can cause severe eye and skin burns, leading to permanent damage. Repeated high exposure can result in an asthma-like allergy, so that, on re-exposure, asthma attacks occur with shortness of breath, wheezing, cough and/or tightness of the chest. Bronchitis may also be another complication.
In contrast to these toxic effects, the low level exposures cause mild symptoms, as set out above. However when there is Multiple Chemical Sensitivity (MCS), (in which formaldehyde is almost universally one of the troublesome chemicals – petrochemicals and derivatives being the other main chemicals in MCS) or specific sensitivity to formaldehyde, the symptoms that result on exposure, even to minimal levels, can be severe and often debilitating and even, rarely, life-threatening – a type of anaphylactic reaction.
Physical and Chemical Properties of Formaldehyde.
The common name is formaldehyde. Its systematic name is methanol. Other names (frequently used) are formalin, formol, methylaldehyde, methylene oxide and formicaldehyde.
Formaldehyde is a colourless gas with a pungent smell. It is the simplest aldehyde and its chemical formula is H2CO or CH2O or HCHO. Although it is a gas at room temperature, it is readily soluble in water. It is most commonly sold as a 37% aqueous solution with trade names such as Formalin or Formol. In water, formaldehyde converts to the hydrate CH2(OH)2, thus Formalin contains very little H2CO.
Formaldehyde is readily oxidized by atmospheric oxygen to form formic acid. Thus formaldehyde solutions should be protected from air, to prevent deterioration.
Industrially, formaldehyde is produced by catalytic oxidation of methanol.
Formaldehyde is measured in parts per million (ppm) in the air. Most adults react to formaldehyde at a range of 0.5-1.5 ppm – this is a toxic effect. Those with chemical sensitivity, sometimes referred to as specific allergic reaction, react to much lower levels – a hundredth or less, ie less than 0.005ppm. This is a hypersensitivity reaction and hence is different to the toxic or poisoning reaction. In remote outdoor locations, the average formaldehyde level is 0.002 to 0.006 ppm. In cities and industrial areas, the level averages 0.01 to 0.05 ppm. Levels depend on multiple factors such as rush hour traffic, type of industry etc.
There is usually more formaldehyde present indoors than outdoors. Formaldehyde is released from many home products (see below).
How Might Formaldehyde Enter my Body?
Formaldehyde can enter the body by inhalation, ie of the gaseous form of formaldehyde in the atmosphere. Many products which contain formaldehyde ‘outgas’. This term means that formaldehyde is released into the atmosphere from the product as a gas. This is why indoor levels of formaldehyde are generally higher than outdoor, by virtue of the enclosed space, especially when there is poor ventilation.
Formaldehyde can also enter the body by contact with solutions containing formaldehyde or by eating or drinking foods containing formaldehyde. Ingested formaldehyde can have different symptoms to inhaled formaldehyde.
COMMON USES OF FORMALDEHYDE: WHAT CONTAINS FORMALDEHYDE
Formaldehyde is ubiquitous and intrusive and seems to be almost everywhere!
Use in Biology
An aqueous solution of formaldehyde, eg Formalin, can be used as a disinfectant since it kills most bacteria.
It is used as a preservative in some vaccines.
It can be applied topically (to the skin) to dry it and in the treatment of worts (a virus infection).
Formaldehyde preserves of ‘fixes’ tissue or cells. When used in embalming (to disinfect and temporarily preserve human remains) this property results in the tell-tale firmness of the flesh in an embalmed body.
Use in Industry
Formaldehyde was first synthesised by the Russian chemist Aleksandr Butlerov in 1859. It is now one of the world’s most common industrial chemicals. In 1995, 8.1 billion pounds (3.68 billion kilograms) of formaldehyde were produced in the USA, making it the 24th most abundantly produced chemical.
The primary uses for formaldehyde are for the production of polymers and other chemicals. When formaldehyde is combined with urea, phenol or melamine, the resultant chemical is a hard thermoset resin, eg urea-formaldehyde resin. It is also used in the production of plastics and intermediates.
In the construction and building industries, urea-formaldehyde resins and phenol-formaldehyde resins are used primarily as a permanent adhesive in the manufacturer of pressed wood products:
These formaldehyde-emitting (outgassing) pressed woods are widely used in the construction of homes, from the subfloor to rafters, from cabinet veneers to wall panelling, from cupboards to kitchen countertops.
Formaldehyde can also be found as a preservative in:
carpets – mainly in the backing material
foam in cushions.
In the 1970’s, a common use of formaldehyde in the house was in urea-formaldehyde foam insulation (UFFI). This was sprayed, as a foam, into wall cavities, above ceilings etc. This type of cheap insulation begins to deteriorate after exposure to high humidity and temperatures and, as a result, in many homes, the air levels of formaldehyde were high. Especially was this so in mobile homes/caravans. In 1982, UFFI was banned by law in the USA. In 1983, this law was overturned, but the marketability of UFFI had been destroyed.
The production of intermediates is in the manufacture of acetylenic chemicals.
Smaller quantities are used in the production of pentaerythritol, hexamethylenetetramine and urea-formaldehyde concentrates. These are used, for example, to make paints and explosives.
Use in Fabrics
Urea-formaldehyde resin is used in fabrics:
to bind pigments (colour-fast)
as a fire retardant
to create stiffness.
Fabrics are treated with urea-formaldehyde resins to give them all sorts of easy-care properties such as:
permanent press/durable press
anti-cling, anti-static, anti-wrinkle, anti-shrink (especially shrink proof wool)
Use in Household Products
Because it improves not only water resistance, but also grease resistance, shrink-resistance and wet-strength properties, formaldehyde-resins are used in the manufacture of:
paper cups and plates
Use in Personal Care Products
Formaldehyde can be found in items such as:
fingernail polishes and hardeners
Use in Cleaning Products
Formaldehyde can also be found in supplies such as:
Use Outside the Home
Outside the home, for example in the garden or garage, formaldehyde can be used in the manufacture of:
Use on the Farm
On the farm, formaldehyde has been used:
as a fumigant
as a preventative for mildew in wheat and rot in oats
as a germicide and fungicide for plants
as an insecticide
in the manufacture of slow-release fertilisers.
Non-Commercial Production of Formaldehyde
Formaldehyde can be produced by burning carbon-based materials such as:
wood in fireplaces
gas or kerosene heaters (especially unvented/unflued) indoors
cigarettes, cigars and pipe tobacco, especially indoors.
Formaldehyde is also produced naturally, in very small and diluted quantities, by the action of sunlight and oxygen breaking down atmospheric methane and other hydrocarbons.
Who is Especially Likely to be Exposed to Higher Levels of Formaldehyde?
People who work or live at or near chemical plants that make or use formaldehyde can be exposed to higher than natural amounts of formaldehyde.
Certain professionals may also be exposed to higher amounts of formaldehyde:
workers in clothing industry
workers in furniture factories
teachers and students who handle preserved specimens in laboratories.
In my book ‘Why Do I feel So Awful?” (Angus and Robertson 1989), the section on indoor pollution sets out some brief comments about formaldehyde (pages 286-289). To quote from that text, “You Can’t Escape Formaldehyde”. How true!
In this modern day, formaldehyde is almost unavoidable.
How to Reduce Your Exposure to Formaldehyde.
The risk formaldehyde poses to a person’s health depends upon the concentration of formaldehyde in the air.
It can also, for example, depend upon the concentration in the material against the skin. In this instance, the formaldehyde outgases directly onto the skin, which may cause dermatitis, so-called contact dermatitis. Or it can be absorbed through the skin. As well, it can outgas (due to the heat and humidity of the body) into the atmosphere, to be breathed in as the warm air rises.
Also relevant is the length of time the person is exposed, as well as the person’s individual sensitivity to formaldehyde.
For everyone, it would seem prudent to reduce exposure to formaldehyde, especially in the home. However for those who suffer from Multiple Chemical Sensitivity (‘How To Stop Feeling So Awful’, chapter 17, pages 136-145, refer homepage), and for those with a specific sensitivity to formaldehyde, it is essential to keep the exposure as low as practical. In addition to avoidance, the use of specially formulated sublingual neutralising drops, after appropriate testing, can give relief from induced symptoms, as well as provide some protection when exposed to formaldehyde. Chemical neutralising drops are discussed in chapter 19, pages 154-155.
It is virtually impossible to avoid formaldehyde totally. However the following sets out practical guide-lines.
- Purchase products with little or no formaldehyde.
Read the label. Remember, when checking the ingredients listed on the product for formaldehyde, that it may go under a number of aliases that are used to hide or disguise its presence:
formalin or formol
methanol, methylene oxide, oxymethyline, methylaldehdye or oxymehtane
the formula H2C0 or HCHO.
The following are formaldehdyde-releasing preservatives:
· Avoid buying uncoated pressed wood products made with urea-formaldehyde resin. These include the many plywood and particle board products used indoors such as shelving, cabinets and desks.
· Substitute other building materials for formaldehyde-containing pressed wood products such as solid wood furniture, gypsum board, stainless steel, bricks, stone, tiles or hard plastic.
· Never use urea-formaldehyde foam insulation.
· Consider buying antique or second-hand furniture. Formaldehyde outgassing decreases as products age.
· If it is necessary to purchase pressed wood products, then seek out low-emitting products:
Ø Choose pressed wood products using phenol-formaldehyde resin or methylene diisocyanote resin. These products outgas much less formaldehyde then urea-formaldehyde resin products.
Ø Select urea-formaldehyde pressed wood products that are sealed with finishes that reduce formaldehyde outgassing, such as veneer, vinyl or other water-resistant coating. Any bare cut ends of, for example, shelves can be painted with a product such as Estapol which seals in the formaldehyde.
· When using products and appliances that release or outgas formaldehyde, it is essential to:
Ø Exhaust all combustion appliances directly to the outdoors (wood fires, gas or kerosene or other fuel fires) and have annual checks made for both operation and venting.
Ø Wash permanent press clothing, sheets and other fabrics before using. One good wash can reduce the formaldehyde outgassing by up to 60%.
Ø Prohibit all forms of smoking in your home and car.
Ø Air products containing formaldehyde before bringing them indoors and, where appropriate, increase ventilation in the house.
Ø New carpet, furniture, new drapes and other permanent press textiles should be aired in a ventilated warm area for several days before bringing them inside the house.
Ø Keep fresh outdoor air circulating when applying fingernail hardeners, nail polish and other cosmetic products containing formaldehyde. These products can be high emitters. If there is a known sensitivity, never use these and avoid those who do, especially during and immediately after application.
Ø Keep windows and doors open when painting inside the house, or applying, for example, wallpaper.
· New cars are notoriously “smelly” due to outgassing of plastics and formaldehyde and other chemicals. Park the car in the sun, with windows and doors open, as much as possible in the first days and even weeks after purchase. Those with chemical sensitivity often opt for purchase of a near new (for example 9 month old) vehicle which has essentially outgassed.
Remember, formaldehyde is released more quickly when the temperature and/or humidity are high.
Children may be more susceptible than adults to the respiratory effects of formaldehyde because they have a greater lung surface area to body weight ratio, causing them to absorb more formaldehyde from contaminated air, relative to their body weight.
Children in homes and buildings have an additional risk because formaldehyde is slightly heavier than air, so it settles closer to the floor. Because children are shorter, they are thus exposed to slightly higher levels of formaldehyde than adults. Also, the immune system in infants continues to develop after birth and hence they may be more susceptible to certain chemicals such as formaldehyde. Babies crawling on carpets places them closer to this source of outgassing.
Sick Building Syndrome.
‘Sick Buildings’ are essentially the result of indoor pollution commonly found in large buildings that are enclosed, where the windows cannot be opened and are consequently fully air-conditioned. New buildings, or those recently redecorated (for example repainted, with new furnishings such as carpets and furniture) are especially likely to be ‘sick’. Occupants of these buildings become unwell, with acute and/or chronic symptoms. This is called the ‘Sick Building Syndrome’. The symptoms appear to be linked to both the time spent in the building and the concentration of the chemicals, especially formaldehyde, in the air. Typical symptoms are headaches, fatigue, and eye, nose or throat irritation. No specific illness can be identified to explain the symptoms. The symptoms are the result of the indoor pollution. The ‘Sick Building Syndrome” is also referred to as the ‘Tight Building Syndrome’.
In Australia, it is estimated that at least 30% of major city (eg Sydney, Melbourne) buildings are ‘sick’, and the occupants affected. It requires a minimum of 20% of employees to experience symptoms before a building is classified as a ‘Sick Building’.
Formaldehyde is a significant contributor to the Sick Building Syndrome.
Long-term exposure to formaldehyde, even at low levels as can occur in ‘Sick Buildings’, can adversely affect the central nervous system and cause frequent severe headaches or
trigger migraine attacks, depression, mood changes, insomnia, irritability, attention deficit, reduced concentration and continued impairment of dexterity, memory and equilibrium.
To give but one example of the adverse effects, on the nervous system, of formaldehyde and other chemicals involved in the Sick Building Syndrome:
the headache experienced towards the end of a day in the workplace. Yes, headaches are multi-causal (see my April 2006 newsletter Headaches, Migraine and Diet). One of the contributing factors in the genesis of headache or migraine,
and perhaps the main and only one, could be chemicals, such as formaldehyde, in the air-conditioned, recycled air breathed during the day. The contribution to this made by indoor smoking of cigarettes is now drastically reduced with the widespread banning of indoor smoking.
Fatigue is another common symptom.
If the Sick Building Syndrome is suspected, it is possible to arrange for the building to be inspected and the levels of chemicals, such as formaldehyde, measured in the ambient air.
In Australia, one laboratory that takes such measurements is Healthy Buildings International Pty Ltd, 612-9880-2744, email address firstname.lastname@example.org. Alternatively, look under the category “Environmental &/or Pollution Consultants” in the Yellow Pages telephone directory.
A Final Note of Concern
Apart from the adverse health effects listed above, the US Environmental Protection Agency has classified formaldehyde as a probable human carcinogen, and formaldehyde is classified as a known human carcinogen by the International Agency for Research on Cancer.
· Always read the label
· Dress wisely
· Stay informed
· Aim for the lowest personal exposure to formaldehyde as is practical.
** Copyright 2007: The Huntly Centre.Back to the list Print friendly version