JAN 2 970

DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE

PUBLIC HEALTH SERVICE
NATIONAL INSTITUTES OF HEALTH
BETHESDA, MARYLAND 20014

 

December 29, 1969

Dr. J. Lederberg
Genetics Department
Stanford University
Stanford, Califom ia

Dear Dr. Lederberg:

Thank you for your note of December 15. Most of the articles

discussing "zero tolerance" or indeed dose response studies with

carcinogens are listed as references in our paper. There is no

more published so far as we can tell. We would be glad to have
fe additional references if you should run into some yourself.

I do know that a number of unpublished studies deal with dose
response with carcinogens. Hopefully they will see the open
literature soon.

Yasyogsiad wie

I have inquired with our chemotherapy people on aramite. I will
let you know whatever information develops.

Best wishes for the New Year.

  

« Weisburger, Ph.D.
Head, Carcinogen Screening Section
Biology Branch, Etiology
National Cancer Institute

‘ o

4 See Roe chapter on Food in Raven & Roe, Prev. of Cancer & refs. therein.

Gf