An integrated exposure and pharmacokinetic modeling framework for assessing population-scale risks of phthalates and their substitutes

Environment International

Min Zhong¹  Ying Xu²  Zidong Song²  Yaoxing Wu³  John C. Little³  Hongwan Li⁴ 

[1] Bureau of Air Quality, Pennsylvania Department of Environmental Protection, Harrisburg, PA 17101, USA;Department of Building Science and Beijing Key Laboratory of Indoor Air Quality Evaluation and Control, Tsinghua University, Beijing 100084, China;Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA 24061, USA;Department of Civil, Architectural and Environmental Engineering, The University of Texas at Austin, TX 78712, USA;

关键词: SVOCs;    Phthalates;    Exposure modeling;    Pharmacokinetic (PK) modeling;    Physiologically based pharmacokinetic (PBPK) modeling;    Risk assessment;   

DOI  :  

来源: DOAJ

【 摘 要 】

To effectively incorporate in vitro-in silico-based methods into the regulation of consumer product safety, a quantitative connection between product phthalate concentrations and in vitro bioactivity data must be established for the general population. We developed, evaluated, and demonstrated a modeling framework that integrates exposure and pharmacokinetic models to convert product phthalate concentrations into population-scale risks for phthalates and their substitutes. A probabilistic exposure model was developed to generate the distribution of multi-route exposures based on product phthalate concentrations, chemical properties, and human activities. Pharmacokinetic models were developed to simulate population toxicokinetics using Bayesian analysis via the Markov chain Monte Carlo method. Both exposure and pharmacokinetic models demonstrated good predictive capability when compared with worldwide studies. The distributions of exposures and pharmacokinetics were integrated to predict the population distributions of internal dosimetry. The predicted distributions showed reasonable agreement with the U.S. biomonitoring surveys of urinary metabolites. The “source-to-outcome” local sensitivity analysis revealed that food contact materials had the greatest impact on body burden for di(2-ethylhexyl) adipate (DEHA), di-2-ethylhexyl phthalate (DEHP), di(isononyl) cyclohexane-1,2-dicarboxylate (DINCH), and di(2-propylheptyl) phthalate (DPHP), whereas the body burden of diethyl phthalate (DEP) was most sensitive to the concentration in personal care products. The upper bounds of predicted plasma concentrations showed no overlap with ToxCast in vitro bioactivity values. Compared with the in vitro-to-in vivo extrapolation (IVIVE) approach, the integrated modeling framework has significant advantages in mapping product phthalate concentrations to multi-route risks, and thus is of great significance for regulatory use with a relatively low input requirement. Further integration with new approach methodologies will facilitate these in vitro-in silico-based risk assessments for a broad range of products containing an equally broad range of chemicals.

【 授权许可】

Unknown