Grantee Research Project Results
2021 Progress Report: Optimizing use of novel chemicals to assess childrens dust ingestion rates
EPA Grant Number: R840208Title: Optimizing use of novel chemicals to assess childrens dust ingestion rates
Investigators: Bennett, Deborah H. , Young, Thomas M , Kannan, Krunthachalam
Institution: University of California Davis , New York University
EPA Project Officer: Hahn, Intaek
Project Period: June 1, 2021 through May 31, 2024 (Extended to May 31, 2025)
Project Period Covered by this Report: June 1, 2021 through May 31,2022
Project Amount: $1,342,099
RFA: Estimating Childrens Soil and Dust Ingestion Rates for Exposure Science (2020) RFA Text | Recipients Lists
Research Category: Human Health , Children's Health
Objective:
The goals of this project are to: (1) Develop an innovative method for determining dust ingestion rates using compounds found primarily in indoor dust rather than outdoor soil, (2a) Measure dust ingestion in children living in homes from four distinct geographic areas with differing SES, urban/rural/suburban classification, and racial/ethnic composition and an additional cohort of children with autism or developmental delays, (2b) Determine the concentrations of a broad range of target and non-target compounds in house dust to improve understanding of indoor chemical exposures as a function of demographic variables, (3) Measure seasonal and age group variation in dust ingestion rates, and (4) Develop standard procedures for the dust tracer method to support its implementation by other organizations.
Progress Summary:
1. Selection of target compounds: The list of compounds measured in the prior dust study was reviewed again to determine if there were any additional compounds to add to the urinary metabolite panel. The Kannan lab will work to develop a method for 1,3-diphenylguanidine, and has purchased the standard for this compound.
2. Development of protocol: Protocols were developed for the Methods Development portion of the study, including duplicate diet, dermal wipes, multiple urine collections from young children over a 1-2 day period, and dust collection. Protocols were tested extensively by research staff with young children to determine feasibility and parent burden. Urine collection protocols were further refined to accommodate children in the middle of potty training. In addition, we created several tools and aides to assist parents in following the protocols as intended.
3. Participant recruitment: We recruited 9 participants, who had a child aged 2 years to 3.5 years old, for the methods development portion of the study. One participant dropped out right before completing their study activities, leaving 8 active participants. Six participants have completed the initial samples collections for this part of the study and will have an additional dust and urine collected in approximately 6 months. We anticipate 20 participants will complete all study related activities for the method development portion of the study.
4. Sample collection for Methods Development: We started collection of paired duplicate diet, urine, dust and dermal wipe samples from 6 participants. Two participants are planning to collect their samples in the next 2 weeks. Six-month follow-up dust and urine collections will continue through the next year for all participants enrolled in the methods development portion of the study.
5. Collection of questionnaire data: We have collected data from participants in a high risk autism birth cohort and from an autism case control study from over 25 participants. We will use this to identify the range of answers to determine which participants and to determine if there are differences by developmental outcome.
Future Activities:
We plan to finish recruiting our intensive first group of children and analyze the data to determine the best way to streamline the protocol for the larger study. Specifically, to determine which spot urine sample will be best to use. First, using this data, we will impute dust ingestions rates for all the compounds for each child and then apply both the Best Tracer Method (BTM) and the Limiting Tracer Method (LTM) to evaluate candidate tracer chemicals for suitability. The combination of our targeted measurement of diverse compounds present in indoor environments with their associated metabolites will allow the first application of LTM and BTM for estimating dust ingestion rates. Second, we will then look at the variability of the concentrations of those compounds in urine from the various times collected to determine which sample should be included in the main study.
Journal Articles:
No journal articles submitted with this report: View all 1 publications for this projectSupplemental Keywords:
indoor dust, dust Ingestion, hand-to-mouth activityProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.