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Updated: Jan 30, 2026
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Extraction and Analysis of Cortisol from Human and Monkey Hair
Published on: January 24, 2014
29.1K
Radon emanation from human hair.
Frédéric Girault1, Frédéric Perrier1
1Physics of Natural Sites, Institut de Physique du Globe de Paris, Sorbonne Paris Cité, University Paris Diderot, CNRS UMR 7154, F-75005 Paris, France.
The Science of the Total Environment
|January 15, 2019
Summary
Human hair radioactivity, specifically effective radium-226 concentration (ECRa), varies significantly by sex and hair dye use. Understanding these factors is crucial for accurate bio-monitoring and epidemiological studies.
Area of Science:
- Environmental Science
- Radiological Science
- Human Health
Background:
- Human hair serves as a bio-indicator for long-term pollutant exposure.
- Limited research exists on human hair radioactivity in background environments.
- Factors influencing hair radioactivity in both contaminated and background areas are poorly understood.
Purpose of the Study:
- To measure radon-222 emanating power (ECRa) in human hair from non-contaminated areas.
- To determine the emanation coefficient (E) of human hair.
- To investigate factors affecting ECRa in human hair.
Main Methods:
- A high-sensitivity method using 371 long accumulation sessions was employed.
- ECRa was measured in hair samples from 93 individuals.
- Emanation coefficient (E) was also determined for human hair.
Main Results:
- ECRa values in human hair showed significant heterogeneity (0.059–3.7 Bq kg-1).
- Females and individuals with color-treated hair exhibited higher ECRa (2.6x and 2.5x, respectively).
- Emanation coefficient (E) was found to be homogeneous across samples.
Conclusions:
- Human hair displays 226Ra-238U disequilibrium, suggesting secondary radium intake.
- Sex and hair dyeing are significant factors influencing ECRa, likely due to differential heavy element accumulation and radium in hair products.
- The developed method is cost-effective for large-scale epidemiological and forensic studies.
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