Ann. Occup. Hyg., Vol. 56, No. 2, pp. 138–147, 2012 Ó The Author 2011. Published by Oxford University Press on behalf of the British Occupational Hygiene Society doi:10.1093/annhyg/mer088 Predictors of Airborne Exposures to Polycyclic Aromatic Compounds and Total Organic Matter among Hot-Mix Asphalt Paving Workers and Influence of Work Conditions and Practices JENNIFER M. CAVALLARI 1 *, LINDAV. OSBORN 2 , JOHN E. SNAWDER 3 , ANTHONY J. KRIECH 2 , LARRY D. OLSEN 3 , ROBERT F. HERRICK 1 and MICHAEL D. MCCLEAN 4 1 Harvard School of Public Health, Department of Environmental Health, 665 Huntington Avenue, Boston, MA 02215, USA; 2 Heritage Research Group, 7901 West Morris Street, Indianapolis, IN 46231, USA; 3 Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, 4676 Columbia Parkway, Mail stop: C-26, Cincinnati, OH 45226, USA; 4 Boston University School of Public Health, Department of Environmental Health, 715 Albany Street, Boston, MA 02218, USA Received 24 March 2011; in final form 1 September 2011; published online 24 October 2011 Objectives: We evaluated personal airborne exposures to polycyclic aromatic compounds (PACs) and total organic matter (TOM) among hot-mix asphalt (HMA) paving workers. The primary ob- jectives of this study were to identify predictors of airborne PAC exposures, identify PAC exposure sources, and characterize how work practices may affect personal airborne exposure to PACs. Methods: Four workers were recruited from each of three asphalt paving crews (12 work- ers) and were monitored for three consecutive days over 4 weeks for a total of 12 sampling days per worker (144 worker-days). Three sampling weeks were conducted while maintaining stan- dard working conditions with regard to airborne exposures. The fourth week included the sub- stitution of biodiesel for diesel oil used to clean tools and equipment. Linear mixed-effects models were used to evaluate predictors of airborne exposures including weather parameters (air temperature, wind speed, and relative humidity), worksite conditions (HMA application temperature, work rate, asphalt grade, and biodiesel use), and personal factors (minutes sam- pled, minutes of downtime, and smoking status). Results: Concentrations of the 33 individual PACs measured in personal air samples were generally below detection limits under all conditions with the exception of fluorene [geometric mean (GM) 5 65 ng m 23 ], naphthalene (GM 5 833 ng m 23 ), phenanthrene (GM 5 385 ng m 23 ), and pyrene (GM 5 57 ng m 23 ). The summary measures of TOM (GM 5 864 mgm 23 ) and four- to six-ring PAC (GM 5 0.13 mgm 23 ) were detected in the majority of air samples. Although task was not a predictor of airborne exposures, job site characteristics such as HMA application temperature were found to significantly (P £ 0.001) affect summary and individual PAC exposures. Based on the results of multivariate linear mixed-effects mod- els, substituting biodiesel for diesel oil as a cleaning agent was associated with significant (P £ 0.01) reductions in TOM, four- to six-ring PACs, and naphthalene and pyrene concentrations that ranged from 31 to 56%. Using multivariate linear mixed-effects models under standard conditions, reducing the application temperature of HMA from 149°C (300°F) to 127°C (260°F) could be expected to reduce airborne exposures by 42–82%, varying by analyte. *Author to whom correspondence should be addressed. Tel: (617) 432-1979; fax: (617) 432-3441; e-mail: cavallaj@hsph.harvard.edu 138 by guest on February 4, 2016 http://annhyg.oxfordjournals.org/ Downloaded from