Development of an extraction method for the determination of dissolved organic radiocarbon in seawater by accelerator mass spectrometry

Tanaka, Takayuki; Otosaka, Shigeyoshi  ; Amano, Hikaru; Togawa, Orihiko 

We developed an extraction system of carbon from dissolved organic carbon (DOC) to achieve its accurate and precision C measurement by AMS. The system was devised for reducing the blank carbon by decreasing the contamination of dead carbon mainly induced from oil products and CO in air, and for extracting it from large volume seawater. The developed system gained lower blank than the previous studies to be less than 1% of sample size. It was demonstrated that the C value extracted from organic material by the system of lower blank was agreed with that by the conventional combusted method and the precision was very low value of 5‰. Results indicated that the system achieved the high accuracy and precision for C. We tied to measure DOC in large volume seawater and confirmed the great extraction and good precision to be 8‰. Results revealed that the system attained the supreme accuracy and precision for DOC in large volume seawater.