title: A Novel Method for Calculating Potency-Weighted Cumulative Phthalates Exposure with Implications for Identifying Racial/Ethnic Disparities among U.S. Reproductive-Aged Women in NHANES 2001-2012.
abstract: Phthalates are ubiquitous chemicals linked to hormonal disruptions that affect reproduction and development. Multiple antiandrogenic phthalates exposure during fetal development can have greater impacts than individual exposure; thus, the National Academy of Sciences (NAS) recommends them for cumulative assessment. Using National Health and Nutrition Examination Survey data (NHANES, 2001-2012), we developed a potency-weighted sum of daily intake (∑androgen-disruptor; μg/kg/day) of di-n-butyl phthalate (DnBP), diisobutyl phthalate (DiBP), butyl benzyl phthalate (BBzP), and di(2-ethylhexyl) phthalate (DEHP) based on NAS recommendations, and included diethyl phthalate (DEP) and diisononyl phthalate (DiNP) in additional metrics (2005-2012). We compared racial/ethnic differences in ∑androgen-disruptor among 2842 reproductive-aged women. In sensitivity analyses, we assessed the influence of potency assumptions, alternate urine dilution adjustment methods, and weighting phthalate metabolites directly rather than daily intake estimates of parent compounds. We found that DEHP contributed most to ∑androgen-disruptor (48-64%), and that ∑androgen-disruptor decreased over time. Black women generally had higher cumulative exposures than white women, although the magnitude and precision of the difference varied by model specification. Our approach provides a blueprint for combining chemical exposures linked to common adverse outcomes, and should be considered in future exposure, risk, and epidemiological studies.
authors: Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley , Berkeley, California 94720, United States.
authors: Julia R
authors: JR
authors: Varshavsky
authors: Department of Environmental and Occupational Health, Milken Institute School of Public Health, George Washington University , Washington, D.C. 20052, United States.
authors: Ami R
authors: AR
authors: Zota
authors: Program on Reproductive Health and the Environment, Department of Obstetrics, Gynecology, and Reproductive Sciences, Institute for Health Policy Studies, University of California, San Francisco , San Francisco, California 94143, United States.
authors: Tracey J
authors: TJ
authors: Woodruff
mesh_terms: D003993:Dibutyl Phthalate / Q000378:metabolism; D004781:Environmental Exposure; D004785:Environmental Pollutants; D005260:Female; D006801:Humans; D009749:Nutrition Surveys; D010795:Phthalic Acids; D012098:Reproduction
chemical_list: D004785:Environmental Pollutants; D010795:Phthalic Acids; D003993:Dibutyl Phthalate