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Updated: Jun 24, 2026
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Sampling and Pretreatment of Tooth Enamel Carbonate for Stable Carbon and Oxygen Isotope Analysis
Published on: August 15, 2018
Using medical accelerators and photon activation to determine Sr/Ca concentration ratios in teeth
1Nuclear Science and Technology Development Center, National Tsing Hua University, Hsinchu 300, Taiwan, ROC. jhchao@mx.nthu.edu.tw
Summary
This study introduces a photon activation method using medical accelerators to measure strontium (Sr) and calcium (Ca) in teeth. This technique offers a sensitive way to determine Sr/Ca ratios for biological and archaeological research.
Area of Science:
- Nuclear Physics
- Analytical Chemistry
- Biogeochemistry
Background:
- Strontium (Sr) and Calcium (Ca) levels in teeth and bones are important indicators in biological and archaeological studies.
- Accurate determination of Sr/Ca ratios can provide insights into diet, migration, and environmental conditions.
- Existing methods for elemental analysis may have limitations in sensitivity or sample preparation.
Purpose of the Study:
- To develop and validate a photon activation analysis (PAA) method for determining Sr and Ca concentrations and their ratios in human tooth samples.
- To assess the feasibility of using medical accelerators as photon sources for this analytical technique.
- To evaluate the detection sensitivity and minimum detectable amounts for Sr and Ca using PAA.
Main Methods:
- Utilized two medical accelerators (15 and 18 MeV) as photon sources for photon activation.
- Irradiated tooth samples and measured the resulting radionuclides using gamma-spectrometry with a high-purity germanium (HPGe) detector.
- Identified radionuclides via their characteristic gamma-ray emissions and calculated photonuclear reaction yields.
- Estimated detection sensitivities and minimum detectable amounts for Sr and Ca.
Main Results:
- Successfully determined Sr and Ca levels and Sr/Ca ratios in deciduous and permanent tooth samples.
- Achieved a minimum detectable amount for Sr of less than 1 microgram per gram (µg g⁻¹).
- Reported Sr/Ca ratios of 0.390 mg g⁻¹ for deciduous teeth and 0.565 mg g⁻¹ for permanent teeth.
Conclusions:
- Photon activation analysis using medical accelerators is a viable and sensitive method for determining Sr/Ca ratios in teeth.
- The method's sensitivity and the use of readily available medical accelerators make it suitable for biological and archaeological applications.
- This technique provides a valuable tool for investigating past environments and human behaviors through skeletal remains.
