Formaldehyde is a chemical commonly used in the manufacture of building materials and numerous household products. At room temperature, formaldehyde vaporises into the air, potentially causing serious health problems. It is also a by-product of combustion processes. When you burn things like natural gas, wood, petrol, or tobacco, formaldehyde gas is released into the air. The most significant sources of formaldehyde in homes are: pressed wood products like particle board, plywood, and MDF (medium density fibreboard); foam insulation; carpets; drapery fabrics; resins; glues; cigarettes; and poorly-vented, fuel-burning appliances like gas stoves or kerosene heaters.
Health effects of formaldehyde are eye, nose and throat burning and irritation; nausea; skin rashes; and breathing difficulties in some people. High concentrations of formaldehyde can trigger asthma attacks. Formaldehyde is also considered a known human carcinogen (cancer-causing substance), and classified as a Hazardous Air Pollutant (HAP) by the EPA. The World Health Organisation specifies a limit for formaldehyde in air of 100 ug/m3, which is equivalent to 80 - parts-per-billion (ppb).
Since formaldehyde is present in so many building materials and household products, every home should be tested for the presence of this toxic chemical.