Are you preparing to sell your home? Did you have urea-formaldehyde foam insulation installed in my attic back in the 70's and now you must complete a disclosure statement on any hazards that may exist in the home and you're wondering if this type of insulation hazardous?
Pure formaldehyde gas (vapors) has been listed as a probable human carcinogen, though formaldehyde in non-vapor forms is not considered carcinogenic. Urea-formaldehyde foam is a solid product, so contact with the foam is not dangerous.
The process of installing the foam involved taking liquid monomer and reacting it so that it becomes a solid. This process is called polymerization. In the process of polymerization, some formaldehyde is released into the atmosphere. As the foam is setting up, smaller amounts of formaldehyde may be released to the air. However, there is a finite amount of formaldehyde that is available for off-gassing, so over time, the formaldehyde being emitted decreases steadily. Studies have shown that within two years of application, with an air exchange rate of 0.3 (i.e. in one hour, 30% of the air in the attic space has been replaced by outside air), half of the available formaldehyde has been released. Since it has been nearly 20 years since the insulation was installed, it is entirely probable that little or no available formaldehyde remains in the insulation.
Urea-formaldehyde insulation is not the only source of formaldehyde in the home. Many products use formaldehyde during the manufacturing process. Formaldehyde consistently ranks among the top 50 manufacturing chemicals by volume. It is a common ingredient in many household furnishings and consumer products. In household furnishings, it is a component of carpeting, particle board, vinyl products, and foam used in furniture and construction; in consumer products, it is used as a preservative in cosmetics, in room deodorants, disinfectants and fumigants, and numerous medicinal applications such as athlete's foot treatment, mouthwash, spermatocide cream, skin disinfectants, and cough drops. It is also a component in cigarette smoke; it is used as a disinfectant in mattresses; and as a component of "permanent press" fabric finishes. Finally, formaldehyde is synthesized within the human body as a natural metabolite of methanol. Because this is so, the human body has built in mechanism to metabolize formaldehyde. This metabolic pathway must be overwhelmed before adverse affects are observed. Because each person reacts differently, it is hard to say at exactly what level of exposure adverse affects begin to occur.
Adverse health affects associated with formaldehyde, particularly in occupational settings, include irritation of the eyes, nose, and throat. It can cause bronchial spasm and pulmonary irritation, particularly in sensitive individuals (e.g. asthmatics). Occasionally individuals may have acute severe reaction to formaldehyde, but rarely it is life threatening. Since the most severe acute symptoms of formaldehyde exposure is associated with inhaling it, individuals with compromised respiratory systems may wish to limit their exposure to products from which formaldehyde may off-gas (for example, an asthmatic may avoid ironing permanent press fabrics as the heating action of the iron may liberate formaldehyde from the permanent press fabric finish).
Because there are so many sources of formaldehyde emissions in the home, the presence of urea-formaldehyde foam insulation 20 years after installation should not significantly affect the overall quality of the home. In fact, the alternative, fiberglass insulation, may have health risks of its own.
NOTE: The U. S. Environmental Protection Agency has additional information and a Comprehensive Procurement Guideline Program (CPG) to promote the use of materials recovered from solid waste. Here it is:
Insulation made from recovered materials is available for thermal insulating applications. The product is available in several forms including rolls, loose-fill, and spray foam. Insulation also can include a range of recovered materials such as glass, slag, paper fiber, and plastics. One manufacturer grinds postconsumer glass bottles into a substitute for the sand used in glass fibers. Others use slag for rock wool or old newspaper for cellulose insulation.
EPA's RMAN recommends recycled-content levels for purchasing building insulation as shown in the table below.
for Building Insulation
The recommended recovered materials content levels are based on the weight (not volume) of materials in the insulating core only.
In 1993, the American Society for Testing and Materials (ASTM) issued a standard for the composition of cullet used in the manufacture of fiberglass insulation, D 5359, "Glass Cullet Recovered from Waste for Use in Manufacture of Glass Fiber." EPA recommends that procuring agencies reference this specification in Invitations for Bid and Requests for Proposals.