Estimating Children's Exposure to Persistent Organic Pollutants Using Pharmacokinetic Modeling

Wednesday, February 8, 2017 4:10:00 PM - Wednesday, February 8, 2017 5:30:00 PM
Rm.149(basement), Earth Sciences Building, 5 Bancroft Ave.
Environment & Health Seminar

MARC-ANDRE VERNER, Assistant Professor, Department of Occupational and Environmental Health, School of Public Health, Université de Montréal

ABSTRACT: Children are extensively exposed to multiple environmental chemicals through placental transfer and breastfeeding. Quantifying children’s exposure is challenging because it is impractical to collect biological samples during infancy and childhood. To circumvent this methodological limitation, pharmacockinetic models of pregnancy and lactation have been developed for persistent organic pollutants known to transfer from the mother to the fetus/child. The precision and accuracy of these models have been evaluated against measured maternal and child blood levels of multiple chemicals (e.g., polychlorinated biphenyls, hexachlorobenzene, perfluorooctanoic acid). Validated models have subsequently been used in epidemiology and risk assessment to estimate children’s prenatal and lactational exposure to chemicals. During this presentation, I will describe pharmacokinetic model development for persistent organic pollutants and discuss approaches to assess model sensitivity (i.e., local and global sensitivity analyses) and to validate models. Applications in the context of longitudinal birth cohorts will also be presented, with examples of how estimated children’s plasma levels has allowed the identification of critical windows of vulnerability to toxic insults (e.g., neurotoxicity, immunotoxicity). Finally, two examples of how pharmacokinetic modeling has been used to assess prenatal and lactational exposure to chemicals in the context of risk assessment will be presented. 

BRIEF BIO: Marc-André Verner works as an Assistant Professor at the Department of Occupational and Environmental Health, School of Public Health, Université de Montréal (Canada). He is also a member of the Université de Montréal Public Health Research Institute (IRSPUM). Marc's research projects focus mostly on physiologically based pharmacokinetic (PBPK) modeling and quantitative structure-property relationships (QSPR) to evaluate developmental exposure to environmental chemicals in the womb and postnatally through breastfeeding. He earned his Ph.D. in Biology from the Université du Québec à Montréal (Canada). During his Ph.D., Marc developed PBPK models of persistent organic pollutants to refine exposure assessment in epidemiologic studies of breast cancer and developmental neurotoxicity. After completing his Ph.D., he continued working on PBPK modeling during his postdoctoral training at the Karolinska Institutet in Sweden. He then moved to Boston (USA) to do a second postdoctoral training in environmental epidemiology at the Harvard Medical School/Brigham and Women's Hospital. His background in both toxicology and environmental epidemiology led him to pioneer the use of PBPK modeling in epidemiologic studies, an approach that allowed reconstructing complete exposure profiles and investigating the effects of chemicals during different windows of vulnerability. Over the years, Marc has authored and co-authored approximately 25 peer-reviewed papers and received numerous awards for his innovative work in environmental health.