C FICIAL USE ONLY ICONS PROGRAM, LOS ALAMOS SCIENTIFIC LABORATORY, Dr, John Kirby-Smith, Assistant Director for Biological Sciences, DBM, reported on the current status of the ICONS (Isotopic, Carbon, Oxygen, Nitrogen and Sulfur) production at Los Alamos indicating that Carbon-13 continues to be produced in the existing two columns at a rate in excess of 6 kilo per year. The rebuilt NO column at the DP West site is expected to be in operation by November 1971 with an expected production rate of approximately 1.5 kilo/yr of 15y and 450 kilo/yr. of l4y Engineering design is continuing for the new isotope facility to be built at Los Alamos for the integrated production of all the stable isotopes of carbon, nitrogen and oxygen. Contracts for the drilling of holes to contain the let in the near first of these ICONS distillation columns are to be future. Dr. D. C. Borg, DBM, discussed the plans for clinical studies at LASL. He reported on a meeting that was held at LASL on 14 January 1971 to explore the possibility of inter-laboratory collaboration on a 13¢ clinical demonstration program, The meeting was informal in character and grew out of the express need of LASL and of DBM to establish a firm market for 13¢-1abeled products. Clinical use of carbon-13 had appeared most promising as a “market" for volume use of the isotope that would be most accessible at an early time. Shreeve of BNL prepared for the meeting a list of possible clinical diagnostic applications of C that served as the nucleus for discussion. The group concluded that a clinical test was feasible, and preliminary plans were made for a pilot study, which is now in_ the process of being set up. Oxidation of orally administered glucose-1-!3¢ as a sensitive screening test for diabetes was selected for the initial carbon-13 clinical demonstration after weighing a number of considerations. These included patient availability, prior documentation with 14¢ studies, diagnostic usefulness, a high incidence of the clinical condition being studied, the availability of an appropriate 13¢ labeled material for a loading study, the efficiency of utilization of the 13¢ label, and the ease and facility of obtaining samples for detection. Shreeve proposed to carry out preliminary clinical tests during the first half of 1972, when he would be a visiting scientist at LASL, Further studies would be carried out with a patient group obtained from his present clinical program at BNL or his affiliations with the ‘Madowbrook Hospital on Long Island. Each patient would undergo paraliel studies with 14¢- 1abeled glucose, and intravenous glucose tolerance tests and other documentations would also be carried out to insure the greatest possible clinical relevance of the limited number of !3c¢ studies that could be done, using 1-13¢-glucose prepared by Ott and Gregg, of LASL. Primary 13¢ measurements on alkaline samples containing expired CO. from patients would be made with a gas chromo- tograph/mass spectrograph (GC/MS) apparatus in Klein's laboratory at ANL, Modifications to increase the sensitivity of separating mass ratios 44 and 45 would be undertaken directly by Klein, and if preliminary tests indicate that significant gains in detection sensitivity may be confidently expected, development of an inexpensive (less than $20,000) prototype GC/MS instrument for routine stable isotope determination in clinical laboratories would be undertaken, OFFICIAL USE ONLY