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Biomonitoring and Nonpersistent Chemicals-Understanding and Addressing Variability and Exposure Misclassification
Judy S LaKind1,2, Fadwa Idri3, Daniel Q Naiman4
1LaKind Associates, LLC, 106 Oakdale Ave, Catonsville, MD, 21228, USA.
Current Environmental Health Reports
|February 1, 2019
Summary
Single urine samples are unreliable for measuring exposure to nonpersistent chemicals. Multiple samples collected over time are essential for accurate toxicological exposure assessment and reproducible results.
Area of Science:
- Environmental Health
- Toxicology
- Biomarker Research
Background:
- Intraindividual variability in urinary biomarkers complicates exposure assessment for nonpersistent chemicals.
- Accurate exposure assessment is crucial for understanding chemical toxicity and health risks.
Purpose of the Study:
- To review intraindividual variability in urinary biomarkers for nonpersistent chemical exposure.
- To provide recommendations for improving the evaluation of nonpersistent chemical exposure.
Main Methods:
- Systematic review of studies reporting intraclass correlation coefficients (ICCs) for urinary biomarkers.
- Analysis of reproducibility categories and potential for participant misclassification.
Main Results:
- Most reported ICC values indicate poor to good reproducibility, with significant participant misclassification even in "good" categories.
- Single spot measurements of nonpersistent chemicals in urine are demonstrably unreliable for exposure assessment.
Conclusions:
- Multiple urine samples, collected over a relevant toxicological period and considering exposure patterns, are necessary for reliable assessment.
- Adequate resources must be allocated to properly characterize exposures to nonpersistent chemicals to avoid inconsistent research findings.
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