Isolation of individual fatty acids in sediments using preparative capillary gas chromatography (PCGC) for radiocarbon analysis at NIES-TERRA

Compound-specific radiocarbon analysis (CSRA) of individual fatty acids (140-1190 mug C) in an estuarine sediment sample collected from Tokyo Bay was carried out using a recently developed preparative capillary gas chromatography (PCGC) system and accelerator mass spectrometry (AMS). The results showed that the estimated C-14 ages of four components greatly varied from modern age (combined iso and anteiso C-15:0, C-16:0) to 17 000 years BP (C-22:0), while a hulk-phase C-14 age of organic matter is 5000 years BP. The C-14 ages of the fatty acids derived from phytoplankton and bacteria are much younger than that of the bulk phase. On the other hand, the fatty acid originated from terrestrial higher plants (C-22:0) shows an older C-14 age of 17 000 years BP. (C) 2000 Elsevier Science B.V. All rights reserved.