72 
eliminated. I think we need to address what the purpose of a particular 
safeguard is and see whether it is appropriate to apply it. I think fil- 
tration of general exhaust air is an important function of experiments that 
indeed represent a unique hazard to a community, and these types of studies 
should be confined to a P4-like facility. 
MR. DACH: I agree with the cost-effectiveness approach. I would 
just like to be confident that the other areas of containment have been 
pushed to their cost potential, and at that point if you wanted to say 
that it was a problem of allocation of resources, I would be better con- 
vinced than I am now. 
DR. FREDRICKSON: Dr. Sturgis. 
DR. STURGIS: I would like to ask Dr. Barkley a question. Are there 
any data on neighborhood epidemics due to exhaust from laboratories similar 
to the neighborhood epidemic cases of berylliosis, for instance? 
DR. BARKLEY: Not associated with laboratory activities. There have 
been cases of infection in communities that have been associated with lab- 
oratory operations, but they have been where an agent has been transmitted 
from a diseased laboratory worker to a contact at home. 
MR. DACH: Have people looked and found nothing, or they haven't looked? 
DR. BARKLEY: Dr. Wedum, when he was alive, did do a study which was 
contained in the analysis of Fort Detrick, where he studied specifically 
31 what he called laboratory microepidemics, where there was more than 
one laboratory-acquired infection, some as many as over 100 resulting from 
explosions of centrifuges that were in corridors, some with very virulent 
and resistant organisms like Q fever. He was not able to associate any 
incidence of disease in communities in studying those specific microepi- 
demics in laboratories, but he did note that the safeguards employed in 
working with brucellosis, anthrax, or Q fever were basically safeguards 
that we commonly associate with PI, and there were indeed no facility safe- 
guards, and indeed no primary safeguards. I think its presence would have 
been noted. 
Now, I can't say that it has been exhaustively studied to show that 
it can never happen, but certainly we haven't seen evidence that it has 
occurred . 
DR. FREDRICKSON: I think that is probably all the time we have now 
for this discussion. Just to clarify the record, however, the last col- 
loquy has not been on the matter of infections arising from recombinant 
DNA research. It is infections in general, is that correct? 
DR. BARKLEY: That is correct. 
[ 276 ] 
