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Cumulative risks - Biomarkers of Exposure
Biomarkers of exposure are defined as the chemical, its metabolites(s), and/or the biologically active molecule that can be measured qualitatively or quantitatively in a human biological sample following an exposure to the chemical. Biomarkers of exposure indicate, retrospectively, that an exposure has occurred. However, without additional data, these measures do not provide information on: the sources or levels of exposure; when, where, how, or how many times the exposure occurred; or any relationships between exposure and health effects. Recent technological advances in genomics, proteomics, and metabonomics are providing exposure scientists with new tools for investigating and relating changes in endogenous chemicals that can be used to characterize an individual's exposure to a single chemical or a mixture of chemicals.
NERL research is designed to develop tools (methods, models, protocols) that can be used in future studies for measuring biomarkers of exposure and provide high quality data to Agency risk assessors for future cumulative risk assessments. NERL's research focuses on:
- Developing and applying low burden methods (i.e., saliva) for collecting biomarker data, where burden relates to both the impact on the individual providing the samples and the resources required to collect and analyze the samples
- Assessing the variability of biomarker measurements over time
- Developing and using physiologically-based, pharmacokinetic (PBPK) models to reconstruct exposure and environmental concentration from biomarker measurements
- Developing and using PBPK models to estimate target tissue dose from biomarker measurements
- Using mathematical and statistical methods to describe the relationship between exposure measurements and biomarker data
- Developing tools for guiding the collection of biomarker samples for future studies