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Updated: Jun 26, 2026
11:19
Measuring Carbon-based Contaminant Mineralization Using Combined CO2 Flux and Radiocarbon Analyses
Published on: October 21, 2016
REPLACEMENT RATES FOR HUMAN TISSUE FROM ATMOSPHERIC RADIOCARBON
Science (New York, N.Y.)
|November 27, 1964
Summary
Carbon-14 from nuclear testing is present in human tissues, reflecting atmospheric levels. However, cartilage collagen shows very slow Carbon-14 uptake, even in adults exposed to high levels.
Area of Science:
- Environmental Science
- Radiochemistry
- Human Physiology
Background:
- Atmospheric testing of thermonuclear weapons between 1961-1962 significantly increased global Carbon-14 levels.
- Carbon-14 (¹⁴C) is a radioactive isotope used to trace biological processes and environmental changes.
Purpose of the Study:
- To investigate the distribution and uptake rates of atmospheric Carbon-14 in various human tissues.
- To assess the long-term retention and turnover of Carbon-14 in human collagen, particularly in cartilage.
Main Methods:
- Analysis of Carbon-14 concentrations in diverse human tissues, including brain and cartilage.
- Comparison of Carbon-14 levels in individuals from the Northern and Southern Hemispheres.
- Examination of tissue replacement rates using Carbon-14 as a tracer in subjects traveling between hemispheres.
Main Results:
- Human tissues, including the brain, show Carbon-14 levels correlating with atmospheric concentrations from several months prior.
- Cartilage collagen exhibits a significantly slower Carbon-14 uptake rate compared to other tissues.
- Adults aged 70, exposed to high atmospheric ¹⁴C (1954-1964), showed negligible Carbon-14 in cartilage collagen.
- Individuals from the Southern Hemisphere currently display minimal increases in tissue Carbon-14.
Conclusions:
- Human tissue Carbon-14 levels serve as a marker for recent atmospheric exposure, with a time lag.
- Cartilage collagen demonstrates exceptionally slow turnover, indicating long-term stability.
- Tissue replacement rates vary significantly across different tissue types, with cartilage being particularly stable.
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