Settle D M, Patterson C C
Science. 1980 Mar 14;207(4436):1167-76. doi: 10.1126/science.6986654.
Lead contamination in canned tuna, exceeding natural concentrations 10,000-fold, went undiscovered for decades because of analytical error. The magnitude of this pollution effect helps explain the difference between the lead concentration in the diets of present-day Americans (0.2 part per million) and inthe diets of prehistoric peoples (estimated to be less than 0.002 part per million). It also explains how skeletal concentrations of lead in typical Americans became elevated 500-fold above the natural concentrations measured in bones of Peruvians who lived in an unpolluted environment 1800 years ago. It has been tacitly assumed that natural biochemical effects of lead in human cells have been studied, but this is not so because reagents, nutrients, and controls used in laboratory and field studies have been unknowingly contaminated with lead far in excess of naturally occurring levels. An unrecognized form of poisoning caused by this escessive exposure to lead may affect most Americans because magnitudes of biochemical dysfunctions are proportional to degrees of exposure.
罐装金枪鱼中的铅污染，超过自然浓度10000倍，由于分析误差，几十年来一直未被发现。这种污染效应的程度有助于解释当今美国人饮食中铅浓度（百万分之0.2）与史前人类饮食中铅浓度（估计低于百万分之0.002）之间的差异。它还解释了典型美国人骨骼中的铅浓度是如何比1800年前生活在未受污染环境中的秘鲁人骨骼中测得的自然浓度高出500倍的。一直以来人们默认已经对铅在人体细胞中的自然生化效应进行了研究，但实际并非如此，因为实验室和实地研究中使用的试剂、营养物质和对照品在不知不觉中被铅污染，其含量远远超过自然水平。这种因过度接触铅而导致的未被认识到的中毒形式可能会影响大多数美国人，因为生化功能障碍的程度与接触程度成正比。
