Fox J G, Boylen G W
Am J Vet Res. 1978 Jan;39(1):167-9.
Analyses for lead content were done on 124 specific feed ingredients from 5 major pet food companies. The lead content of the different ingredients varied from 0.1 parts per million (ppm) to 3,600 ppm. Of the samples 48 (39%) had greater than 1 ppm lead. In particular, one type of ingredient (mineral mix) was contaminated with large amounts of this element. Feeds that contain a marked amount of lead could add an uncontrolled variable to experiments using laboratory animals and could cause misinterpretation of experimental results.
对来自5家主要宠物食品公司的124种特定饲料成分进行了铅含量分析。不同成分的铅含量从百万分之一（ppm）到3600 ppm不等。在这些样本中，48个（39%）的铅含量超过1 ppm。特别是，一种成分（矿物质混合物）被这种元素大量污染。含有大量铅的饲料可能会给使用实验动物的实验增加一个无法控制的变量，并可能导致对实验结果的错误解读。
