February 19, 1969

Dr. Thomas H. Jukes

Space Sciences Laboratory
University of California
Berkeley, California 94720

Dear Tom:
Thank you for continuing to press me about DDT.

I am enclosing a letter that I wrote recently to Senator Gaylord Nelson,
whom I have some small personal contact with from my Wisconsin days. I
would urge you to communicate directly with him on this subject, expressing
the kinds of concerns that you raised in your letters to me.

My general position is that any compound as biologically effective as DDT
had better not be allowed to accumulate in the environment, which DDT does
appear to do so remarkably. The public health applications of DDT are also
likely to be prejudiced by its indiscriminate use, which can only help to
accelerate the development of resistant varieties.

Sincerely yours,

*

Joshua Lederberg
Professor of Genefttcs

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