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Page 10 of Attachment H 
The preventive medicine and health surveillance aspects of these pro- 
grams are available to all Lilly employees and are mandatory for laboratory 
and production workers. 
Factors involved in several of these areas provide a series of 
redundancies for safety. The 10L limitation as (opposed to 9.2L, 9.5L or 
500L) was an arbitrary figure selected without consideration for industrial 
application. The most widely used organism at the industrial level is 
_E. col i K12. Laboratory strains of _E. col i were originally selected for 
recombinant work because it was the single microorganism which was best 
understood genetically, and any concerns about risk associated with it were 
largely based on the fact that Z. col i was a normal component of the flora 
of the intestinal tract in man and animals. It has been demonstrated 
repeatedly that there is no significant colonization capacity for K12 and 
several of its derivatives. Having reestablished that fact for any 
modified Z. col i — K12— EK1 host-vector system, other risk studies taken out 
Moreover, industrial scale fermentation of a wild type £_. col i has 
been going on for more than thirteen years with no evidence, to our 
knowledge, of any occupational health problems and Lilly has had direct 
experience with this fermentation with no problems. I am enclosing a 
preprint of a historical review of this industrial experience which was 
presented at the recent FDA Symposium on the State of the Art: Insulin and 
of context have no real significance. 
Growth Hormone. 
[ 446 ] 
