Lead Levels and Child Development

Abstract

In the December 1974 issue of this journal, J. Perino and C.B. Ernhart reported that moderate levels of lead exposure in 80 preschool, urban, black children were related to cognitive impairment. In October of 1985, C.B. Ernhart, B. Landa, and A.W. Wolf pre-sented a re-analysis of the data reported in the 1974 article. These researchers revised the position originally taken by Perino and Ernhart and concluded, based on their re-analysis, that if there was an effect of lead levels on cognitive development, it was minimal.

In the June/July 1986 issue of this journal, H.L. Needleman presented an argument against the methodology used in the re-analysis of the data by C.B. Ernhart and her colleagues. He felt that it was inappropriate to conclude, based on such a data analysis, that the relationship of lead level and cognitive development was of little consequence in the sample of children. C.B. Ernhart, in a response to his argument in the June/July 1986 issue, continued to support the re-analysis and findings.

Correspondence regarding the data analysis has continued, and I asked five mem-bers of the JLD Board of Consulting Editors to review the articles, data, and correspon-dence on this matter. After careful study, we all agreed that because of the importance of the topic, space should again be devoted to it. In the following Commentary, Ernhart and Needleman present statements on their respective positions; I will conclude with a brief editorial statement.—JLW

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References

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