pimiuf LLLER

EW YORK UNIVERSITY MEDICAL CENTER| . APR281989° *
Institute of Environmental Medicine ae e OF THe presides

550 FIRST AVENUE, NEW YORK, N.Y. 10016 .
AREA 212 679-3200 “

ANTHONY J. LANZA RESEARCH LABORATORIES AT UNIVERSITY VALLEY
LONG MEADOW ROAD, STERLING FOREST, TUXEDO, N.Y.
MAIL AND TELEPHONE AODRESS: 550 FIRST AVENUE, NEW YORK, N.Y. 10016

April 25, 1980

Dr. Joshua Lederberg
President

The Rockefeller University
New York, New York 10021

Dear Josh:

In reply to your inquiry of April 3, I have scanned my files
for relevant information on the radioprotective effects of chemicals
with respect to radiation carcinogenesis. The best summary I can
come up with is the enclosed United Nations Report. As you can see
from the enclosure, there is some evidence of dose-reducing activity
of sulfhydryl compounds (AET and cysteamine) in experimental
carcinogenesis, but the data are somewhat inconsistent. At most,
the observed protection amounts to a dose-reduction factor of no
more than 2-3. Clearly, the data are skimpy and limited to acute
exposures in the high dose range (hundreds of rads).

As to radioprotection in the diagnostic dose range, I know of
no cogent data. It is noteworthy, however, that AET and cysteamine
must be given at relatively high dose levels to confer Protection
on mice, and comparable levels in human beings* are likely to be
toxic.

I don't know whether this subject is still under Study at ORNL
or BNL, but I think that John Yuhas (Dept. of Radiology, University

of New Mexico School of Medicine) is actively pursuing it.

Best regards.
Sincerely,

Arthur C. Upton, M.D.
Professor and Chairman

ACU/1w

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