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CHARGE NUMBER: PROJECT TITLE: PROJECT LEADER: WRITTEN BY: PERIOD COVERED: DATE OF REPORT: 2501 Nuclear and Radiochemistry of Smoke Roger A. Comes Bobby Francis July T- July 31, 1981 August 7, 1981 Low Level Laboratoryl Construction of the L.L.L. is underway. Grading is complete and footings are now being dug for the foundation. Soil samples are currently being counted on the low background a-$ system. Samples were taken at the surface and at 18" beaow grade. Both samples were dried and placed in a muffle furnace at 900 C for 24 hours prior to counting. Additional: samples of soil, building, materials and aggregate are being prepared for establish- ment of background activity levels and for comparison with literature data on such materials. Counting Systemsl'Z Several of the radioactivity counting systems within the project have become obsolete. A concerted effort is underway to provide new count- ing systems incorporating the best features experience has shown to be necessary and to limit the number of manufacturers with which we have to deal. As a prototype, a system has been placed in operation which should sattsfy our needs for many years to come. A proposal will be presented that in the future all counting systems be designed around a Berthold preamplifier and counting tubes with standard nim-bins and electronics being provided by Ortec. Greenhouse 14C-Tobacco Run #71'Z Following the harvest (Charge #2506) of the tobacco from G.H. Run #7 analyses were conducted to determine the specific activity of the leaf from the top, middle, and bottom portions of each of the four "C02- chamber grown plants. Oven dried samples from cuttings of each leaf position were combusted, trapped,, and assayed by liquid scintillation counti~ng.

-2- Ave. Specific Activity/pci/g Plant-1 Plant-2 P1ant-3 Plant-4. Top Leaf 488 555 499 582 Mid'Leaf 370 550 462 556 Bottom Leaf 329 430 289 400 , El As previously observed, specific activity increases from bottom to top. Plant-to-plant differences are indicative of the four varieties of plant grown in this run as described in the monthly report for Charge #2506. Harvey Oxi:dizer3''"'5 An ongoing experiment utilizing the Harvey Oxidizer to assay TPM pads has led to somewhat surprising results. Zn order to establish the feasibility of the technique, attempts were made to "spike" portions of Cambridge pads with known l"C-compounds such as 14C-glucose, 14C-menthol, and 1"C-dotriacontane. Results from this study indicate that recovery of the activity is very low ranging in the 10 to 30% range. Proper operating procedures for the Harvey call for a combustion "standard" to be run immediately before and after any series of unknowns. These standards, purchased from NEN,; are found to be consistently on target, which indicates that the oxidizer is functioning properly. The study of this "spiking" problem is to be continued. Meanwhile it has been determined that a pad containing TPM from smoking a 14C-dotriacontane cigarette may be analysed by the Harvey technique with good resul~ts. For example, a 14C-dotriacontane. cigarette was smoked and analyzed on the total recovery smoki'ng machilne and was found to contain 12.00 uci activity. Utilizing the Harvey oxidizer for analysis yielded 12.22 uci: activity. The problem to be solved is to determine why good results can be obtained from TPM pads containing 14C from labelled ctgarettes but cannot be obtained when.l"C-materials are spiked directly onto the pad. I"C-Menthol Smoke Studys,s Work is continuing on the study to determine menthol deliveries, total smoke distributions and MS breakdown products from several filtered cigarettes. Samples of 14C-menthoI were purified by preparative HPLC (Charge #2525) and were characterized by GLRC. Chemical and radiochemical purity was shown to be >99%. The menthol was taken up in abs ethanol and concentrated to a volume containing approximately 5uCi 14C-menthol/40V1 EtOH. This solution was used to hand' spike 105 cigarettes consisting of 25 2R1 and'20 each filtered Merit, Meri.t Ultra Lights, Virginia Slims and Benson & Hedges at a target level of SpCi/cigarette. The cigarettes were placed'into individual silylated vials for equilibration and storage. Smoke studies will begin as soon as section data shows that total menthol equilibration throughout rod and filter has taken place.

-3- Miscellaneous 1,s,7,a 1. Two radiochemistry courses have been planned: a) a two sessi'on course for analytical, personnel who may be required to handle radioactive materials and b) a 5 session course for Charge #2525 and 2501 personnel who will require more in-deptfi study. 2. After thorough evaluation, of available instrumentation, a Vista-64 gas chromatograph was recommended and subsequently ordered. This system will be used to continue our studies on smoke precursor-product relationships. 3. A method for the 'quantitative analysis of methanol in head space was developed and'used' to analyze several tobacco samples for Charge #1901. 4. A formal inventory and location defined for all Sr-90 sources has been completed. This is our official record of inventory as required in materials license #45-00385-04. References 1. A. Frisch NB 7309 2. B. Francis NB 7486 3. K. Barlow NB 7547 4. R. Newman NB 4818 5. M. Chavis NB 7615 6. F. Greene NB 7336 7. G. Segura NB 7502 8. D. Douglas NB 7064 .