An integrative approach for estimating children’s soil and dust ingestion rates

EPA Grant Number: R840209
Title: An integrative approach for estimating children’s soil and dust ingestion rates
Investigators: Li, Li , Li, Dingsheng , Fu, You , Son, Yeongkwon , Khlystov, Andrey , Samburova, Vera , Liu, Yan
Institution: University of Nevada - Reno , Desert Research Institute
EPA Project Officer: Hahn, Intaek
Project Period: June 1, 2021 through May 31, 2024
Project Amount: $1,341,123
RFA: Estimating Childrens Soil and Dust Ingestion Rates for Exposure Science (2020) RFA Text |  Recipients Lists
Research Category: Human Health , Children's Health


Accurate and reliable estimates of children’s dust/soil ingestion rates are critical for assessing children’s chemical exposure and associated health risks. This research seeks to develop an innovative integrative approach, which fuses analytical, computational, observational, and statistical methods, to estimate dust/soil ingestion rates of children aged 6 months through 6 years with demographic and environmental variabilities. Our specific aims are to: (Aim 1) Develop an innovative hybrid method for estimating dust/soil ingestion rates through a combination of analytical, computational, observational, and statistical methods; and (Aim 2) Explore the determinants of the variabilities in dust/soil ingestion rates. These specific aims are to test two hypotheses: (1) Synergizing multiple chemical measurements and inter-individual toxicokinetic variabilities enables quantifying inter-individual variabilities in dust/soil ingestion rates; and (2) dust/soil ingestion rates differ between children associated with different demographic and environmental factors, or those associated with different microenvironmental features and behaviors.


We will recruit ~150 children aged 6 months through 6 years with different demographic and environmental features from daycare centers in Reno, NV. We will measure the concentrations of 23 biomarkers in their urine, based on which we will back-calculate the daily intake doses of corresponding environmental chemicals using a reverse dosimetry model and then estimate the total dust/soil ingestion rates using structural equation modeling. Using multivariate linear regression, we will examine whether the estimated total dust/soil ingestion rates differ significantly between various demographic and environmental factors. We will also follow the systematic observation approach to observe the frequency of children’s touching and mouthing activities, based on which we will develop a behavior-driven dust/soil ingestion model to predict the dust/soil ingestion rate from microenvironmental features and child behavior.

Expected Results:

This project will provide exposure scientists with a hybrid approach to estimate the dust/soil ingestion rate in a defensible and accurate manner (for Aim 1), and will provide health and risk assessors tabulated, stratified estimates of dust/soil ingestion rates for subgroups of children of interest and a holistic computational tool for population- or site-specific assessments (for Aim 2). Overall, this project is anticipated to increase our capacity to protect children from chemical exposure via dust/soil ingestion.

Supplemental Keywords:

dust, soil, ingestion, children, decision-making, modeling, demographic, behavior

Progress and Final Reports:

  • 2021