【摘要】 目的　测定不同年龄人牙胶原蛋白中的14 C浓度 ,以了解几十年来世界范围内因核试验生成的14 C对中国的环境污染和人体中14 C浓度的影响。方法　从 192 0～ 1977年间出生的上海居民中收集到的牙齿中挑选永久第 8齿 48只 ,经去污、脱钙、提取胶原蛋白 ,再经高温氧化、精制、还原成石墨 ,用加速器质量分析计 (AMS)测定δ14 C ,并用δ13C进行修正 ,求得Δ14 C浓度。结果　δ14 C在 (- 2 9 5 1± 15 0 2 )‰和 (5 75 88± 2 1 0 9)‰之间 ,Δ14 C在 (- 2 7 0 1± 15 32 )‰和 (5 80 34±2 1 5 2 )‰之间 ,且随出生年份不同有显著变化 ,各试料的δ14 C和Δ14 C之差在δ14 C和Δ14 C的标准差的 1/ 3以下。结论　随出生年份不同牙齿胶原蛋白中14 C浓度有显著变化 ,1940年前出生的Δ14 C值属本底水平 ,从 1941年开始呈明显上升趋势 ,至 195 1年前后出生的达最高峰 ,约为 5 80‰ ,以后呈缓慢减少 ,这与以前报道的植物、人体组织中14 C浓度变化有相似倾向 ,与 1990年报道的日本人牙齿中14 C浓度变化相一致 ,并与世界范围内大气层中核试验次数密切相关。更多还原

【Abstract】 Objective The concentration of 14 C in the collagen of the teeth among people with different ages was measured to understand concentration of 14 C in the environment and human body of China influenced by 14 C produced by nuclear weapon tests in the world in the past decades. Methods Forth eight eighth permanent teeth of some Shanghai residents born from 1920 to 1977 were collected. The teeth were cleaned and decalcified for the extraction of collagen and then were oxidized by high temperature and reduced into carbide graphite. The 14 C was measured using an accelerator mass spectrometer (AMS),and the concentration of 14 C was obtained by correction of 13 C. Results The concentration of 14 C in the collagen of the teeth showed apparent variation in people born in different years:those born before 1940 around the level of background and those born from 1941 gradually increase,those born 1951 reached the peak value 580‰,those born after 1951 presented a tendency of decrease. Conclusion The results of this study indicated there is the same tendency of change in concentration of 14 C in teeth and previously reported human tissue and plant. Also there is same variation in concentration of 14 C in both Chinese and Japanese teeth; it also correlates with the numbers of atmospheric testing of nuclear weapons in the world.更多还原