MUTAGENS OF POTENTIAL SIGNIFICANCE 237 



45) , and the phenomenon may be just as important, especially to 

 counteract the effect of radiation. 



Novick: That should read "Novick and Szilard," for the record, 

 instead of the present statement of only Novick. 



Zamenhof: If I may add one word more, I would rather subscribe 

 to what Dr. Goldstein said, that there may be other dangerous agents 

 lurking in the dark. One example is acetaldehyde, which nobody would 

 suspect until it was pointed out. Perhaps caffeine is not the most im- 

 portant. Perhaps this calculation is not the most important. But it is 

 important to have a case where these things have been brought to the 

 scientist's attention. 



Goodgal: Scientists have the responsibility not to raise issues that 

 are not based on fact. If it is demonstrated that caffeine is a mutagenic 

 agent in a large variety of organisms, and under a variety of condi- 

 tions, or one can at least define them, then I think there is a much 

 more solid basis for raising this issue. My own feeling is that there 

 has been too much said today on too few facts. 



Lederberg: This is not a completely new issue. It has been brought 

 up before. I wrote a letter about it to the Bulletin of Atomic Scientists* 



*Text inserted at Dr. Lederberg's request in lieu of informal discussion at the 

 conference : 



To the Editor: 



Several writers, notably Professor Curt Stern, have emphasized that any use of 

 atomic energy entails a calculable risk, no less than those features of modern 

 technology that lead to auto accidents and gastric ulcers. Nuclear warfare poses 

 such an immediate and overwhelming peril to simple survival that concern for 

 the ultimate genetic hazards of atomic energy betokens an almost unwarrantable 

 optimism for the maintenance of world peace, but an optimism that is our only 

 constructive recourse. However, if we postulate survival, we cannot overlook the 

 long run genetic problems entirely for preoccupation with the narrower issues of 

 public affairs. 



As the bulletin shows, the attention of the informed public is rightly focussed 

 on the production of deleterious mutations by penetrating radiations, but this 

 emphasis may have obscured the possibly wider contact of genetic hygiene with in- 

 dustrial civilization. Radiobiological discussions have often taken the spontaneous 

 mutation rate as a reference base, as an unavoidable evil which could not be 

 averted and ought not be aggravated. However, recent studies have established 

 two relevant facts: 1. A variety of chemical reagents can also induce mutations. 

 Many of these compounds are special drugs, but the list also includes such com- 

 mon substances and natural metaboUtes as formaldehyde, hydrogen peroxide, and 

 caffeine. 2. Still other chemicals can reverse these mutagenic effects and can 

 also reduce the "spontaneous" mutation rate. Much (but by no means all) of 

 this research has been conducted with microorganisms and more extensive studies 

 are needed to establish, for example, whether the germ cells of man are physio- 



