# Assessing the accuracy of exposure measurements for common endocrine disrupting chemicals

> **NIH NIH R21** · WASHINGTON STATE UNIVERSITY · 2022 · $374,480

## Abstract

PROJECT SUMMARY
Our ten-year project supporting the collection and analysis of human fetal ovaries was abruptly
halted four years ago when high levels of BPA in some maternal urine samples in our cohort
raised suspicion about our analytical prowess. We secured one year of R56 funding and used it
to verify the accuracy of our new direct analytical method and demonstrate that older indirect
methods on which human estimates of BPA exposure have been based do not accurately capture
levels of the major BPA metabolite, BPA-glucuronide (BPA-G). Our data suggest human BPA
exposure has been significantly underestimated. Further, because glucuronidated metabolites of
other endocrine disrupting chemicals are measured using similar indirect methods, our findings
raise concern that this may be a pervasive problem. The proposed pilot studies begin to address
this concern by focusing on three chemicals that represent three different classes of endocrine
disrupting chemicals. We will develop direct methods using authentic standards for the major
metabolites of the three chemicals and use these methods to assess the accuracy of currently
used indirect methods for measuring them in human biospecimens. We postulate that, like BPA,
we will find inaccuracies in indirect analyses for at least two of the three. Because human
biomonitoring data are used to obtain estimates of human exposure and these estimates, in turn,
are essential in safety assessments, the proposed studies have the potential to affect not only
human epidemiological studies designed to assess the effects of these chemicals on human
health, but also to upend chemical risk assessment.

## Key facts

- **NIH application ID:** 10508301
- **Project number:** 1R21ES034457-01
- **Recipient organization:** WASHINGTON STATE UNIVERSITY
- **Principal Investigator:** Patricia Hunt
- **Activity code:** R21 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2022
- **Award amount:** $374,480
- **Award type:** 1
- **Project period:** 2022-09-06 → 2024-08-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10508301

## Citation

> US National Institutes of Health, RePORTER application 10508301, Assessing the accuracy of exposure measurements for common endocrine disrupting chemicals (1R21ES034457-01). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/10508301. Licensed CC0.

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