Grantee Research Project Results

Understanding and predicting disparities in organic contaminant levels in blood among the U.S. population

EPA Grant Number: SU840684
Title: Understanding and predicting disparities in organic contaminant levels in blood among the U.S. population
Investigators: Li, Li
Institution: University of Nevada - Reno
EPA Project Officer: Page, Angela
Phase: I
Project Period: March 1, 2024 through May 12, 2025
Project Amount: $74,999
RFA: 20th Annual P3 Awards: A National Student Design Competition Focusing on People, Prosperity and the Planet Request for Applications (RFA) (2023) RFA Text |  Recipients Lists
Research Category: P3 Awards , P3 Challenge Area - Chemical Safety

Description:

It has long been acknowledged that chemical exposure and risks differ significantly among demographic groups due to diverse lifestyles, socioeconomic status, culture-related behaviors, genetics, ontogeny, and physiology. Nevertheless, most existing computational exposure models are based on a “standard” or “average” adult human that represents the central-tendency characteristics of a population, and therefore, lack the capability to generate protective outcomes for the most “at risk” subpopulations. 

Objective:

The objective of this project is to improve and utilize advanced computational models to understand and predict disparities in organic contaminant levels found in the American population. Specifically, we seek to illustrate the model-based predictions of the variability in blood concentrations of three case-study phthalic acid esters, accounting for the impacts of inter-individual variabilities in demographics-related factors, including diets, metabolism, physiology, and anthropometrics, on the toxicokinetics of chemicals. The central hypothesis is that these mentioned factors interactively determine the absorption, distribution, and elimination of chemical contaminants, and therefore, their inter-individual variabilities can lead to differential levels of organic contaminants among different demographic groups.

Approach:

Specific aims include: (Aim 1) Upgrade an exposure and toxicokinetic model named PROTEX in support of calculating chemical blood concentrations with an improved capability of considering interindividual variabilities in chemical absorption, metabolism, and elimination; (Aim 2) Develop databases of demographics, physiology, anthropometrics, and diet information for individuals participating in the U.S. National Health and Nutrition Examination Survey; (Aim 3) Estimate variations in blood concentrations of three case-study phthalic acid esters to examine disparities in their blood levels between demographic groups. As part of the project, the research findings and environmental justice concerns related to chemical substances will be conveyed to graduate and undergraduate students at the University of Nevada, Reno through engaging lectures integrated into the Environmental Exposure Assessment course, as well as broader audience through a training course at an academic conference. 

Expected Results:

The insights and tools derived from this project can be valuable for academic researchers, regulatory bodies, and chemical industry to gain in-depth understanding of disparities in human chemical exposure and enact customized policy measures tailored to vulnerable subpopulations, ultimately contributing to the equitable distribution of benefits and burdens related to chemical substances and a balance between economic “wealth” and environmental “health”. These insights and tools will also be useful for chemical exposure and risk assessment efforts under the Toxic Substance Control Act.

Supplemental Keywords:

toxicokinetic modeling, chemical exposure, risk assessment, environmental justice, disparity

Progress and Final Reports:

2024

Final