Estimated daily intake of phthalates in occupationally exposed groups.
Hines-CJ; Hopf-NBN; Deddens-JA; Silva-MJ; Calafat-AM
J Expo Sci Environ Epidemiol 2011 Mar-Apr; 21(2):133-141
Improved analytical methods for measuring urinary phthalate metabolites have resulted in biomarker-based estimates of phthalate daily intake for the general population, but not for occupationally exposed groups. In 2003-2005, we recruited 156 workers from eight industries where materials containing diethyl phthalate (DEP), dibutyl phthalate (DBP), and/or di(2-ethylhexyl) phthalate (DEHP) were used as part of the worker's regular job duties. Phthalate metabolite concentrations measured in the workers' end-shift urine samples were used in a simple pharmacokinetic model to estimate phthalate daily intake. DEHP intake estimates based on three DEHP metabolites combined were 0.6-850 microg/kg/day, with the two highest geometric mean (GM) intakes in polyvinyl chloride (PVC) film manufacturing (17 microg/kg/day) and PVC compounding (12 microg/kg/day). All industries, except phthalate manufacturing, had some workers whose DEHP exposure exceeded the U.S. reference dose (RfD) of 20 microg/kg/day. A few workers also exceeded the DEHP European tolerable daily intake (TDI) of 50 microg/kg/day. DEP intake estimates were 0.5-170 microg/kg/day, with the highest GM in phthalate manufacturing (27 microg/kg/day). DBP intake estimates were 0.1-76 microg/kg/day, with the highest GMs in rubber gasket and in phthalate manufacturing (17 microg/kg/day, each). No DEP or DBP intake estimates exceeded their respective RfDs. The DBP TDI (10 microg/kg/day) was exceeded in three rubber industries and in phthalate manufacturing. These intake estimates are subject to several uncertainties; however, an occupational contribution to phthalate daily intake is clearly indicated in some industries.
Analytical-methods; Phthalates; Biomarkers; Urinalysis; Biological-monitoring; Metabolites; Sampling; Pharmacodynamics; Kinetics; Rubber-manufacturing-industry; Rubber-workers; Exposure-levels; Exposure-assessment; Employee-exposure;
Author Keywords: phthalates; biomonitoring; personal exposure
Cynthia J. Hines, National Institute for Occupational Safety and Health, 4676 Columbia Pkwy, R-14, Cincinnati, 45230, USA
84-74-2; 84-66-2; 117-81-7
Journal of Exposure Science and Environmental Epidemiology