title: Tracking contributions to human body burden of environmental chemicals by correlating environmental measurements with biomarkers.
abstract: The work addresses current knowledge gaps regarding causes for correlations between environmental and biomarker measurements and explores the underappreciated role of variability in disaggregating exposure attributes that contribute to biomarker levels. Our simulation-based study considers variability in environmental and food measurements, the relative contribution of various exposure sources (indoors and food), and the biological half-life of a compound, on the resulting correlations between biomarker and environmental measurements. For two hypothetical compounds whose half-lives are on the order of days for one and years for the other, we generate synthetic daily environmental concentrations and food exposures with different day-to-day and population variability as well as different amounts of home- and food-based exposure. Assuming that the total intake results only from home-based exposure and food ingestion, we estimate time-dependent biomarker concentrations using a one-compartment pharmacokinetic model. Box plots of modeled R2 values indicate that although the R2 correlation between wipe and biological (e.g., serum) measurements is within the same range for the two compounds, the relative contribution of the home exposure to the total exposure could differ by up to 20%, thus providing the relative indication of their contribution to body burden. The novel method introduced in this paper provides insights for evaluating scenarios or experiments where sample, exposure, and compound variability must be weighed in order to interpret associations between exposure data.
authors.affiliation: Department of Public Health Sciences, University of California Davis, Davis, California, United States of America.
authors.forename: Hyeong-Moo
authors.initials: HM
authors.lastname: Shin
authors.affiliation: Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America; School of Public Health, University of California, Berkeley, California, United States of America.
authors.forename: Thomas E
authors.initials: TE
authors.lastname: McKone
authors.affiliation: Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory, Berkeley, California, United States of America.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Sohn
authors.affiliation: Department of Public Health Sciences, University of California Davis, Davis, California, United States of America.
authors.forename: Deborah H
authors.initials: DH
authors.lastname: Bennett
mesh_terms: D000393:Air Pollutants / Q000009:adverse effects*; D015415:Biomarkers / Q000378:metabolism*; D001822:Body Burden; D004777:Environment; D004781:Environmental Exposure / Q000009:adverse effects*; D004784:Environmental Monitoring / Q000379:methods; D005502:Food / Q000009:adverse effects; D006207:Half-Life; D006801:Humans; D008962:Models, Theoretical
chemical_list: D000393:Air Pollutants; D015415:Biomarkers