Background: phthalates are used as plasticizers and solvents in industrial, medical, and consumer products; however, occupational exposure information is limited. Objectives: we sought to obtain preliminary information on occupational exposures to diethyl phthalate (DEP), di-n-butyl phthalate (DBP), and di(2-ethylhexyl) phthalate (DEHP) in a cross-section of industries. Methods: we recruited 156 workers in 2003-2005 from eight industry sectors. Mid- and end-shift urine samples were analyzed for phthalate metabolites. We assessed occupational contribution by comparing creatinine-adjusted end-shift concentrations to mid-shift and U.S. general population concentrations. Results: evidence of occupational exposure to DEHP was strongest in polyvinyl chloride (PVC) film manufacturing and PVC compounding, to DBP in phthalate manufacturing and rubber gasket manufacturing, and to DEP in phthalate manufacturing. Each of these sectors used or produced the indicated phthalate. Geometric mean end-shift (GMend) concentrations of the DEHP metabolites, mono(2-ethyl-5-hydroxyhexyl) phthalate and mono(2-ethyl-5-oxohexyl) phthalate, were highest in PVC film (151 and 84.6 µg/g, respectively), and PVC compounding (102 and 60.8 µg/g, respectively). DEHP monoester was highest in nail-only salons (GMend = 19 µg/g). DBP monoester was 12-fold higher in rubber gasket (GMend = 418 µg/g) than in nail-only salons (GMend = 34.2 µg/g). DEP monoester decreased within-shift in all sectors, except in phthalate manufacturing which produced DEP (GMend = 716 µg/g). GMend phthalate metabolite concentrations frequently exceeded U.S. general population concentrations even when no workplace use was reported. Conclusions: using phthalate urinary metabolites, we successfully identified workplaces with occupational phthalate exposure. Additional work is needed to distinguish occupational from non-occupational sources in low-exposure workplaces.
Work-environment; Exposure-assessment; Exposure-methods; Occupational-exposure; Epidemiology; Biohazards; Biological-effects; Biological-factors; Biological-monitoring; Biological-systems; Chemical-hypersensitivity; Exposure-assessment; Exposure-levels; Exposure-limits; Exposure-methods; Urine-chemistry; Statistical-analysis; Workplace-studies
Epidemiology; ISEE 20th Annual Conference, Pasadena, California, October 12-16, 2008