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Published on: April 24, 2014
Oxidation method affects radiocarbon analysis of natural solid samples: Implications for elemental analyzer vs.
Seung-Cheol Lee1, Gwan-Ho Lee2, Hyunshin Koh3
1Environmental Planning Institute, Seoul National University, Seoul 08826, Republic of Korea.
Marine Pollution Bulletin
|July 21, 2026
Summary
Radiocarbon dating relies on elemental analyzer combustion (EAC) and closed tube combustion (CTC) sample preparation. While generally agreeing, these methods show significant differences for low-carbon environmental samples.
Area of Science:
- Geochemistry
- Environmental Science
- Archaeology
- Marine Science
Background:
- Radiocarbon analysis is crucial for dating in environmental studies, archaeology, geochemistry, and marine science.
- Elemental analyzer combustion (EAC) and closed tube combustion (CTC) are standard methods for preparing solid samples for 14C analysis.
- A direct comparison of EAC and CTC using diverse environmental samples is needed.
Purpose of the Study:
- To compare the performance of elemental analyzer combustion (EAC) and closed tube combustion (CTC) methods for radiocarbon analysis.
- To evaluate the agreement between EAC and CTC across various environmental sample types.
- To identify conditions where discrepancies between the two methods may arise.
Main Methods:
- Comparison of fraction modern (F14C) values obtained from EAC and CTC.
- Analysis of diverse environmental matrices with varying carbon concentrations.
- Statistical evaluation of agreement and discrepancies between the two methods.
Main Results:
- Both EAC and CTC methods yielded comparable F14C values for most environmental samples.
- A significant discrepancy (up to 30%) in F14C values was observed for samples with low carbon concentration (<1% by weight).
- Methodological differences, particularly combustion time, may influence results for heat-resistant organic matter.
Conclusions:
- While EAC and CTC are largely comparable, method selection is critical for low-carbon environmental samples.
- The prolonged combustion in CTC might be advantageous for complete oxidation of recalcitrant organic matter.
- Further investigation is warranted, especially considering the increasing use of automated EAC in radiocarbon laboratories.
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