There has been concern about the release of formaldehyde gas from construction material used in the trailer homes used by FEMA for temporary housing. Why the concern over formaldehyde? Formaldehyde is a gas at normal temperatures. It is the simplest member of a class of organic chemicals called “aldehydes.” Most common aldehydes, including formaldehyde, have a sharp, pungent odor. Exposure to formaldehyde can be irritating to eyes, nose and throat. In concentrations of a few parts per million, most people experience intense irritation. At higher concentrations, it may cause cancer.
According to the most recent USEPA estimate, the lifetime risk of cancer from the low-level exposures to formaldehyde in homes is less than 1 part per million. Because formaldehyde has produced nasal cavity tumors in lab animals following intense exposure, the EPA has ranked it as a probable human carcinogen.
Formaldehyde is found in particle board and plywood, in fabric treatments, carpet backing, foam insulation, adhesives, resins, and fabrics. It is a tissue preservative in hospital labs and as an embalming fluid in funeral homes. The greatest exposures to formaldehyde are encountered in morgues, hospital labs, funeral homes and in industrial manufacture of paints, resins, fabrics and adhesives. Formaldehyde is also found in tobacco smoke, automobile exhaust and in other sources of air pollution. In the case of the FEMA trailers, particle-board or plywood used in their construction contain formaldehyde as part of the adhesive that binds the wood together. If the trailers are subjected to direct sunlight, the heat causes some of the residual formaldehyde to evaporate and enter the air inside the trailer. The Centers for Disease Control (CDC) reports an average level of formaldehyde in these trailers of about 80 parts per billion (0.08 parts per million). The current OSHA Permissible Exposure Limit (PEL) for formaldehyde in the workplace is 750 parts per billion (0.75 ppm). While the occupational exposure limit is much higher than that seen in the FEMA trailers, there is still concern about the possibility of respiratory illness in occupants of these temporary housing units, especially the very young and the very old, since they can be present and exposed 24 hours per day; not just for an 8-hour shift.
A truly safe level has not been established. OSHA has set 750 parts per billion as acceptable for an 8-hour workday. EPA says a “safe” level is 100 parts per billion. The World Health Organization says a safe level is 80 parts per billion. The average odor level of formaldehyde is 3 parts per billion. The National Institute of Occupational Safety & Health recommends 16 parts per billion.
The average indoor level of formaldehyde is 10-20 parts per billion. Even the most sensitive individuals do not seem to react at this 10-20 parts per billion range.
Putting all this together would suggest several “safe” levels:
1. The OSHA limit for an 8-hour work day of 0.75 parts per million for the production workplace.
2. The WHO of 80 parts per billion limit for an office environment that will not cause any interference with work.
3. The no reaction level for residences, hospitals and healthcare facilities is 20 parts per billion.
Testing can be done by an experienced and reputable Industrial Hygienist. The highest level of an Industrial Hygienist is a Certified Industrial Hygienist who could perform these tests or oversee the testing of another Industrial Hygienist.