The University of Iowa 
Iowa City, Iowa 52242 
College of Medicine 
Department of Blochemlatry 
1847 
September 23, 1978 
Director 
National Institutes of Health 
Bethesda, Maryland 20014 
Dear Sir; 
I would like to make the following comments concerning the 
proposed revision of the NIH G-uidlines for Recombinant DNA Research; 
1. Because E. coli K12 does not proliferate outside of lab 
environments, I feel that the general lowering of restrictions 
should be carried out at least as far as proposed. Also, I 
am in favor (for the reasons cited in your discussion of the 
proposed revision) of the following points: 
2. Mouth pipetting should not be prohibited under P2 conditions 
and should definately be allowed under PI containment. Mechanical 
pipetting devices may be improving but nothing comes close to 
the efficiency of mouth pipetting. 
3. Eating and drinking should still only be prohibited in the 
work area under P2 conditions. Some labs have office desks 
in the lab (although separated from the lab benches) where 
researchers keep books, files, and perform paperwork. One 
should be allowed to have a cup of coffee or grab a sandwich 
while reading, for example. 
4. In view of the safety of 2. coli K12, P2-EK2 experiments 
should have a P3-EK1 option.” 
Sincerely, 
Bruce Citron 
[A— 323] 
