A new method of in situ CO2 sampling from waters for 14C analysis

14C determination without the application of AMS or small-volume counters with their specific sample preparation lines requires some grams of carbon (1-3 g) for conventional radiometric measurement. For waters of medium carbonate content this is equivalent to the extraction of carbon from 50 to 100 L of water. For low carbonate contents the quantity of water that must be sampled for some grams of carbon can even exceed 1000 L. In this case conventional sampling techniques do not meet the requirements of contamination safety, reasonable effort and selectivity of carbon-extraction. Therefore, a new method of CO2 sampling was developed allowing simple as well as contamination-safe sampling with a reasonable effort. The sampling is selective so that only the CO2 will be bound in the carbon absorber and highly mineralized waters can be sampled as well. (author)