Aldehyde emissions from particleboard and medium density fiberboard products

Indoor air quality problems resulting from the emission of volatile organic compounds (VOCs) have become an issue of increasing concern. Emissions fro m building and furnishing materials, which are frequently constructed from particleboard and medium density fiberboard (MDF), are a potentially import ant contributor of indoor VOCs. In this research, VOC emissions from partic leboard and MDF were measured in small (53-L) stainless steel chambers for 4 days. Samples were collected from 53 of the 61 U.S. mills that produce pa rticleboard and MDF. Each mill identified the predominant tree species used to manufacture the panels. Laboratory tests were conducted at room tempera ture and 45 percent relative humidity. Gas chromatographic/mass spectrometr ic analysis was used to identify and quantify VOC compounds. The predominan t compounds identified in the emissions from particleboard and MDF samples were terpenes and aldehydes, although small straight-chain alcohols and ket ones were also found. This study describes the aldehyde emission data, excl uding formaldehyde. Emissions of small straight-chain aldehydes, such as he xanal, pentanal, heptanal, octanal, and nonanal, generally exceeded emissio ns of other compounds and accounted for more than 50 percent of total VOC e missions. All 53 particleboard and 16 of 18 MDF samples emitted hexanal, th e most prevalent aldehyde found (excluding formaldehyde). The tests showed differences in VOC composition and emission factors by product and tree typ e. On average, aldehyde emissions from southern pine MDF samples considerab ly exceeded the aldehyde emissions from southern pine particleboard. Emissi ons from all other MDF samples, however, were lower than those from particl eboard samples in the same species group. With the exception of formaldehyd e, aldehydes are not added to the adhesives used to bond wood, and they hav e not previously been reported as extractable compounds in wood. Degradatio n of the wood or its secondary metabolites is probably responsible for the presence of the aldehydes.