文摘
The 14C content of 60 human blood serum samples from residents of Malm枚 (Sweden) in 1978, obtained from a biobank, has been measured to estimate the accuracy of 14C bomb-pulse dating. The difference between the date estimated using the Calibomb software and sampling date varied between 鈭?聽卤聽0.4 and +0.2聽卤聽0.5聽years. The average age deviation of all samples was 鈭?.5聽卤聽0.7聽years, with the delay between production and consumption of foodstuffs being probably the dominating cause. The potential influence of food habits on the 14C date has been evaluated using stable isotope 未13C and 未15N analysis and information about the dietary habits of the investigated individuals. Although the group consisting of lacto-ovo vegetarians and vegans (pooled group) was not completely separated from the omnivores in a stable isotopic trophic level diagram, this analysis proved to add valuable information on probable dietary habits. The age deviation of the sampling date from the respective Calibomb date was found strongly correlated with the 未13C values, probably due to influence from marine diet components. For the omnivore individuals, there were indications of seasonal effects on 未13C and the age deviation. No significant correlation was found between the age deviation and the 未15N values of any dietary group. No influence of sex or year of birth was found on neither the 14C nor the 未13C and 未15N values of the serum samples. The data were also divided into two groups (omnivores and pooled group), based on the level of 未15N in the samples. The consumption of high 未15N-valued fish and birds can be responsible for this clustering.