Research Volatile Organic Compounds and Pulmonary Function in the Third National Health and Nutrition Examination Survey, 1988–1994 Leslie Elliott, Matthew P. Longnecker, Grace E. Kissling, and Stephanie J. London National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina, USA BACKGROUND: Volatile organic compounds (VOCs) are present in much higher concentrations indoors, where people spend most of their time, than outdoors and may have adverse health effects. VOCs have been associated with respiratory symptoms, but few studies address objective respira- tory end points such as pulmonary function. Blood levels of VOCs may be more indicative of per- sonal exposures than are air concentrations; no studies have addressed their relationship with respiratory outcomes. OBJECTIVE: We examined whether concentrations of 11 VOCs that were commonly identiﬁed in blood from a sample of the U.S. population were associated with pulmonary function. METHODS: We used data from 953 adult participants (20–59 years of age) in the Third National Health and Nutrition Examination Survey (1988–1994) who had VOC blood measures as well as pulmonary function measures. Linear regression models were used to evaluate the relationship between 11 VOCs and measures of pulmonary function. RESULTS: After adjustment for smoking, only 1,4-dichlorobenzene (1,4-DCB) was associated with reduced pulmonary function. Participants in the highest decile of 1,4-DCB concentration had decrements of –153 mL [95% conﬁdence interval (CI), –297 to –8] in forced expiratory volume in 1 sec and –346 mL/sec (95% CI, –667 to –24) in maximum mid-expiratory ﬂow rate, compared with participants in the lowest decile. CONCLUSIONS: Exposure to 1,4-DCB, a VOC related to the use of air fresheners, toilet bowl deodor- ants, and mothballs, at levels found in the U.S. general population, may result in reduced pulmonary function. This common exposure may have long-term adverse effects on respiratory health. KEY WORDS: air fresheners, air pollution (indoor), deodorants, 1,4-dichlorobenzene, exposure, envi- ronmental exposure, FEV1, lung function, respiratory function tests, VOC. Environ Health Perspect 114:1210–1214 (2006). doi:10.1289/ehp.9019 available via http://dx.doi.org/ [Online 25 April 2006] Volatile organic compounds (VOCs) are a diverse group of chemicals emitted as gases from a variety of commonly used products. The general population is exposed to VOCs from cleaning and degreasing agents, pesti- cides, air fresheners, toilet bowl deodorants, furniture, tobacco smoke, and building mate- rials such as pressed wood products, adhesives, carpeting, paints, and varnishes. Although VOCs are also released into the outdoor air through automotive exhaust and industrial emissions, indoor VOC concentrations are much higher (Wallace et al. 1987, 1991). Because people spend most of their time indoors, health effects related to VOCs in the residential setting are a concern, particularly with respect to respiratory illness (Diez et al. 2000; Farrow et al. 2003; Fiedler et al. 2005; Harving et al. 1991; Koren et al. 1992; Norback et al. 1995; Pappas et al. 2000; Smedje et al. 1997; Venn et al. 2003; Wieslander et al. 1997). Several studies have shown that elevated air concentrations of VOCs are associated with respiratory symp- toms (Diez et al. 2000; Norback et al. 1995; Pappas et al. 2000; Rumchev et al. 2005; Smedje et al. 1997; Wieslander et al. 1997). Studies of VOC exposures and measures of pulmonary function have mostly been small and have used short-term measurements of VOC air concentrations in a single location to 1210 characterize exposures, which may not reﬂect the chronic exposures to these compounds (Fiedler et al. 2005; Harving et al. 1991; Norback et al. 1995; Pappas et al. 2000; Wieslander et al. 1997). Blood concentrations may better reﬂect chronic exposures to VOCs because they integrate exposures from all sources and can be used to estimate internal dose (Ashley and Prah 1997; Ashley et al. 1994; Sexton et al. 2005a). A variety of VOCs were measured in a subset of participants in the Third National Health and Nutrition Examination Survey (1988–1994) (NHANES III) to determine background exposure levels for adults in the general U.S. population (Ashley et al. 1994). Because there is a paucity of information about chronic VOC exposure and pulmonary func- tion, we examined VOC blood concentrations in relation to pulmonary function using data from NHANES III (Ashley et al. 1994). Materials and Methods Study population. We used data from NHANES III and its component Priority Toxicant Reference Range Study, designed to assess the levels of common pesticides and VOCs in a representative sample of the U.S. adult population. The studies were conducted from 1988 through 1994. Detailed informa- tion about NHANES III and the Priority Toxicant Reference Range Study may be found elsewhere [National Center for Health Statistics (NCHS) 1996, 2000]. Briefly, NHANES III is the seventh in a series of peri- odic surveys conducted by the NCHS of the Centers for Disease Control and Prevention designed to provide national estimates of the health and nutritional status of noninstitution- alized U.S. civilians ≥ 2 months of age. The Priority Toxicant Reference Range Study included a sample of 1,338 men and women from NHANES III, 20–59 years of age, selected on the basis of age, race, sex, and region of residence. Among these 1,338 par- ticipants, 1,018 provided an additional blood sample for measurement of VOCs and completed a questionnaire about exposure to various chemical products. Pulmonary function. In NHANES III, spirometry was conducted according to the 1987 American Thoracic Society recommen- dations (NCHS 2001). The National Institute of Occupational Safety and Health (NIOSH) served as the quality control center for the results. Technicians received formal training and satisfactorily completed an NIOSH- approved course on spirometry. Our analyses included forced expiratory volume at 1 sec (FEV1; milliliters), forced vital capacity (FVC; milliliters), peak expiratory ﬂow rate (PEFR; milliliters per second), and maximum mid-expiratory ﬂow rate (MMEFR; milliliters per second). We adjusted all models for race/ethnicity group (indicator variables for African American, Mexican American, and other), age (continuous), age squared (contin- uous), standing height (continuous), body mass index (continuous), and sex, to account for differences in pulmonary function based on these characteristics. We included participants in analyses if they had at least two successful pulmonary function maneuvers and if their results were Address correspondence to S. London, National Institute of Environmental Health Sciences, 111 T.W. Alexander Dr., Building 101, MD A3-05, Research Triangle Park, NC 27709-2233 USA. Telephone: (919) 541-5772. Fax: (919) 541-2511. E-mail: london2@niehs.nih.gov This research was supported in part by the Intramural Research Program of the National Institute of Environmental Health Sciences, National Institutes of Health. The authors declare they have no competing ﬁnancial interests. Received 17 January 2006; accepted 25 April 2006. VOLUME 114 | NUMBER 8 | August 2006 • Environmental Health Perspectives