COMPOSITES AND MANUFACTURED PRODUCTS TERPENE EMISSIONS FROM PARTICLEBOARD AND MEDIUM-DENSITY FIBERBOARD PRODUCTS MELISSA G.D. BAUMANN† STUART A. BATTERMAN GUO-ZHENG ZHANG bility, inability to concentrate, and sleepi- ABSTRACT ness. Trätek, the Swedish Institute of Indoor air quality problems resulting from emission of volatile organic compounds Wood Technology Research (Stockholm, (VOCs) have become an issue of increasing concern. Factors known to affect VOC levels Sweden), estimates that 7 to 10 percent of in indoor air include: ventilation rate, occupant activities, and emissions from building the Swedish population has suffered ill and furnishing materials. In this research, VOC emissions from particleboard and health as a direct result of poor indoor air medium density fiberboard (MDF) were measured in small stainless steel chambers (53 quality, caused in part by VOCs emitted L) during a 4-day period. A protocol was developed to obtain new and representative by building materials and furnishings (2). samples and to minimize contamination of the samples during collection, preparation, Because of increased emphasis on in- and shipment to the laboratory. Samples were collected from 53 of the 61 U.S. mills that door air quality, accurate information is produce particleboard and MDF. Each mill identified the predominant tree species used needed regarding the amounts and types to manufacture the panels. The laboratory tests were conducted at 45 percent relative of VOCs emitted from building materi- als, furnishings, cleaning products, and humidity and used a gas chromatograph and a mass selective detector to identify and other materials found or used in the in- quantify VOC compounds. The predominant compounds identified in emissions from door environment. Such information will the particleboard and MDF samples were terpenes and aldehydes. Small straight-chain allow building occupants, product manu- alcohols and ketones were also found. This study describes the terpene emission data. facturers, building designers and con- Quantified terpenes included a- and b-pinene, camphene, 3-carene, p-cymene, li- tractors, and regulatory and public health monene, and borneol. Terpene emissions accounted for between 7 and 21 percent of the agencies to make informed decisions total VOC emissions, calculated as a-pinene. The highest terpene emissions were about the products they use and recom- observed from particleboard samples manufactured from pines other than southern pine. mend. Increasingly, some product manu- For particleboard, terpene emissions were largely related to the extractive content of the facturers are advertising “low VOC” ma- terials or materials suitable for use by wood species. The terpenes were almost completely absent in emissions from MDF people with chemical sensitivities. samples, which indicates that differences in the manufacturing of MDF compared with Building designers and contractors are the manufacturing of particleboard may have considerably affected emissions. After 4 now being asked to certify that new days, the terpene emissions from all particleboard samples decreased to between 20 and buildings will meet indoor air quality re- 70 percent of their initial values. quirements set by building owners. Ac- curate emissions information is needed to decide which materials will best meet D uring the past several decades, air concentrations include: eye and respira- those requirements while fulfilling struc- quality in homes and office buildings has tory irritation (including asthma), irrita- tural and aesthetic needs. become a matter of increasing concern. Indoor air concentrations of volatile or- ganic compounds (VOCs) are often sig- The authors are, respectively, Research Chemist, USDA Forest Serv., Forest Prod. Lab., One Gifford Pinchot Dr., Madison, WI 53705-2398; Associate Professor and Post-Doctoral nificantly higher than outside due to VOC Associate, Environmental and Industrial Health Univ. of Michigan, 109 Observatory Dr., Ann emissions from building materials, fur- Arbor, MI 48109-2029. The use of trade or firm names in this publication is for reader nishings, and occupant’s activities. This information and does not imply endorsement by the U.S. Dept. of Agriculture of any product problem was exacerbated following the or service. The authors thank the USDA Competitive Grants Program for funding provided to this research program, the National Particleboard Assoc. for funding and assistance in energy crisis in the 1970s as homeowners obtaining samples, Linda F. Lorenz for her work in data collection for this project, and and builders improved the energy effi- Anthony H. Conner for his guidance in getting VOC research started at the Forest Prod. Lab. ciency of their buildings by decreasing air This paper was received for publication in March 1998. Reprint No. 8797. † Forest Products Society Member. exchange rates. Adverse health effects ©Forest Products Society 1999. associated with moderate and high VOC Forest Prod. J. 49(1):49-56. FOREST PRODUCTS JOURNAL VOL. 49, NO. 1 49 The Washington State East Campus bonded with pMDI, and these products EXPERIMENTAL PROCEDURE Plus project (6) provides an example of are for specialized purposes. Emissions SAMPLE COLLECTION how these requirements affect planning. of VOCs potentially can arise from each FROM MILLS During the design and construction of of the materials that compose a panel, but Samples of particleboard and MDF four state office buildings, indoor air attention, until recently, has been on were collected by three National Particle- quality specifications were established emissions of formaldehyde from the UF board Association (NPA) employees dur- that limited VOC emissions from build- resins used to bind particleboard, MDF, ing routine visits to the mills. (In March ing materials and furnishings. To ensure and hardwood plywood. The focus has 1997, the NPA and the Canadian Parti- that these specifications would be met, recently shifted to a variety of VOCs. cleboard Association joined together to many of the building and furnishing ma- form the Composite Panel Association Earlier research (5, 13, 16, 17) identified terials were tested for VOC emissions (CPA)). Sample collection kits were pro- a wide variety of VOCs including ace- prior to installation. For example, speci- vided by FPL, and explicit sample han- fied office furniture systems could emit tone, benzene, hexanal, and toluene emit- dling instructions were given to each of no more than 0.05 ppm formaldehyde ted from composite wood products. the sampling personnel. To prevent expo- and 0.50 ppm total VOCs. Some of these compounds have not pre- sure to or loss of VOCs during shipping, viously been associated with wood prod- In the United States, there are no fed- 300- by 300-mm (12- by 12-in.) panel eral regulations to govern VOC concen- ucts, and there is no ready explanation for samples were sandwiched between two trations in indoor air. However, regula- their presence. Previous studies used pieces of the same panel, wrapped in tory agencies such as the Environmental various types of chambers, different ma- aluminum foil, double-bagged in poly- Protection Agency (EPA) and the Occu- terial loading ratios, a range of air ex- ethylene zipper bags, and placed inside a pational Safety and Health Administra- change rates, a variety of methods for mailing envelope prior to shipping. In- tion (OSHA) have shown an interest in sample collection and storage, and differ- formation about the product type, pre- ensuring that people are not adversely ent analytical procedures. These differ- dominant wood species, additives used, affected by indoor air in their homes and ences make comparison and interpreta- and manufacturing conditions was re- corded at the time of panel sample collec- offices. Development of indoor air VOC tion of the published data difficult, if not tion. General information about each standards is complicated by the follow- impossible. The identification and quan- panel, including resin type and wood ing factors: 1) correlations between prod- tification of emissions from wood prod- species, was provided to FPL along with uct emissions and indoor concentrations ucts (and other materials) should use the panel samples. Sampling was blind in are not straightforward; 2) many VOCs standardized methods as called for by that FPL researchers were not given in- result from occupant activities, including many investigators in the United States formation identifying the individual mill smoking, use of cleaning products or per- and abroad. or manufacturer of each sample. fumes, and cooking; and 3) detection of To answer questions about VOC emis- Panel samples were collected at the specific VOCs at low concentrations sions from wood composite products, we does not indicate whether or not they will mills from March to June of 1997. Upon undertook a study of emissions from un- receipt at FPL, the samples were logged have long-term health effects. finished particleboard and MDF pro- and placed in storage at 2°C until testing Composite wood products such as par- duced in the United States. A similar commenced. A total of 57 particleboard ticleboard, hardwood plywood, and me- study of Canadian-produced products and MDF panel samples were collected, dium density fiberboard (MDF) are has been completed by researchers at including duplicates from four mills. All widely used in indoor products (i.e., sub- Forintek Canada (A.O. Barry, 1995, un- panels were bonded with UF resin, and flooring, door cores, cabinets,