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ROUTING AND TRANSM~AL SLIP 12/17/80 ~&ion File II Note and Return Approval For Clearance As Requestad For Correction Prepare Reply $3rculate For Your Information See Me mment Investigate Signature 00 NOT use this form as a RECORD of approvals, concurrences, disposals, clearances, and similar actions Bruce Wachholz Phone No.
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Department of Energy Lawrence Livermore National zEnclosed are comments Tommy made after reviewing your draft on the Enewetak dose assessment paper. As you can see, they deal almost exclusively with the issue of dietary assumptions, which we all agree is central to the validity of the dose assessments. While at this point we probably are committed to use of the Ujelang diet, many of the points he raises, particularly regarding the compatibility of that diet with Jan Naidu’s values -- which we have had since the summer of 1979 -- are disturbing. The recent Brookhaven National Laboratory report on Rongelap and Utirik chronic dose equivalents, dated October, 1980, also provide disturbing It would be much appreciated if you would give some thought to these points and convey your opinions regarding them to me before the Enewetak document is finalized. Thanks-for your attention -- and welcome home. Office of Health and Environmental Research, Office of Environment
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US. DEPARTMENT OF ENERC Review of “Reevaluation of the Potential Radinlnaieal rmSPS for Residents Resettling Enewetak Atoll”, Draft, UCRL-53966 I kno~’ this draft report on doses at Enewetak Atoll and the new LLNL estimates of doses for Bikini and Eneu Islands at Bikini Atoll represent a lot of work, but I have numerous reservations regarding assumptions that are common to both sets of these estimates. These reservations may be identified as follows: 1. I cannot support ti~e of dietary information commonly an “average” diet for use in predicting average exposures which are then used to estimate maximum exposures. At every opportunity I have spoken against such use in any planning estimates produced by DOE. The survey that produced this diet was conducted on a portion of the population on Ujelang Atoll, which was not a resettled population. This survey produced new and lower estimates of food intake (for most of the important foods) than that used in the past. This survey was initiated and conducted by Micronesia Legal Services (!4LS),legal representatives of the Enewetak people, with the assistance of the school teacher on Ujelang Island. The procedure used in this survey was to ask Ujelang residents to fill out a questionnaire in which estimates were made of how many 12 ounce beverage cans of food (a volume equivalent to this) and liquids each person was consuming. To my knowledge this survey was not based in any way on actual observations of use of food. Using conversion factors, LLNL converted these volume estimates into grams, and also into grams per day intake. This is certainly a tortuous path to get at such important information. So far as I know, no technical report has yet been published on the MLS diet and may never be, nor has there been any independent review of these critical new data or of their impact on dose 2. The MLS diet has two categories for coconut intake; fluid and meat. Naidu’s diet (a diet based in part on actual observation of food use by Jan Naidu, BNL, living with a group of Marshallese) has six; milk, meat, water, flesh, husk, embryo, and sap. The total “no imports” coconut intake level for adult males (fluid and meat) has a mean value of 293 grams per day in the MLS diet. The equivalent for all six items in the Naidu diet (see his letter to Robison dated January 22, 1.980) is 929 grams per day. This is the low end of the range of values obtained from Naidu’s study which applies to the case of no imported food. Naidu’s dietary information was
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transmitted to LLNL last January, so it has been available almost a year. Even so, LLNL states that their report had been essentially completed at the time of receipt of this 3. Looking at the “imports available” column in the draft for the adult female diet, page 71, when 50% of the food is imported, the intake of pandanus, breadfruit, and coconut meat drops by a factor of 3. I would want to see much more information on real world experiences before accepting this large level of reduction. ~~ 4. There is another feature of the MLS diet that seems questionable. Using data in the subject draft, pages 71 and 75, the daily liquid intake for adult females can be obtained. This shows that when imports are available, the total liquid intake is 1,890 grams per day, or just over 4 pints per day. When imported food is not available, the total liquid intake drops to 747 grams per day, or about 1.6 pints, which is less than 1 liter per day. This later value sounds far too low. I would have trouble trying to guess how many 12 ounce beverage cans of liquid I consumed over a year’s time or even yesterday, and it would be even tougher to guess the volume of solid foods I have consumed. We do not know how strong the preference for local fresh food is, compared to dried, powdered, and canned foods, i.e., the im,ported foods. We can assume 50% of the diet will be imported, but the degree to which imports actually replace use of local foods is only a guess. Efforts to provide imported food to residents of Bikini Island were largely a failure. Little if anything was learned about the impact that imported foods may have had on use of local food crops. We have a chicken and egg situation where dietary measurements are needed to support any resettlement plans while people must be resettled to get valid measurements. My current view, and this is based in part on the experience of underpredicting Marshall Island doses in the past, is that because of use of the MLS diet, the dose estimates in the LLNL draft are not conservatively derived, and if used as average doses for imports and no imports, may be too low by a factor of two or more. On the issue of what kind of assessments and evaluations are needed to make good decisions on resettlements, decisions that will be vindicated post-return when the cesium and strontium body burdens have peaked, dose assessments must be conservatively derived and then evaluated against radiation standards in a conservative manner. This was the key to the dose assessments and evaluations in the Enewetak EIS that stood up under many reviews. I expect that these assessments will be
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verified in practice. What DOI needs is practical advice based on realistic assumptions, advice that supports decisions in a way that no retraction is needed later. DOE not only needs to answer questions that DOI asks, but also needs to answer important questions not asked. We must avoid answering questions in a way that DOI does not comprehend the whole I must express particular concern when I observe that both of the conservative elements described above have been dropped in activity intake levels inherent in the MM diet lead to dose assessments that are not~s conservative as in the past, and evaluating such dose as~essments against standards using 500 mrem/year and 5,000 mrem\30 year, and not the 250 mrem/year and 4,000 mrem\30 year developed for the Enewetak cleanup and rehab project, leaves no room for error. In the face of the important decisions that will be based upon LLNL’s report (and particularly when we cannot know what uses and misuses may be made of the report) , it is not enough to state that that doses fo~ some individuals may be higher tfian~redicted. Since the primary concern is health and safety of people, one not base go-no go resettlement decisions only on average dose the average population. This only has meaning for the dose standard for 30 years. One must also limit doses to individuals, even those individuals who for one reason or another get doses much higher than the average. If one looks at the draft objectively, one sees that we are using assumed living patterns, an average diet based upon a questionnaire and not upon any measurements or observations, and average levels of radioactivity in foods that are predicted, not measured. With all these uncertainties, good practice would say predict on the high side and state that doses may be lower. We should be able to state that this report contains conservative estimates of dose, that there are un-
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Rorigelap and Utirik Residents - 1954 to 1980”, adds to this worry. This report indicates that while the maximum deviation from ‘the average value of the daily activity ingestion rate for members of an age subgroup was no greater than a factor of 3, the population distributions illustrated a factor of 5 times the mean activity ingestion rate. The greatest variation in intake was observed to occur in infants, and of 5 times the mean activity ingestion rate. Infants, children, and adults 20 to 40 years of age, ingested more activity each day than adolescents and persons over 40. It is therefore very important to know what ages subgroups will receive the highestiexposure. I am not at all certain we know which group this i-s. It may not be adult males or females. It may be infants born several years after return. How do we explain if doses to infants are greatly My advice is that LLNL’s use of averages or mean values, and conversion factors ~’here there is no data, in calculations of dose to individuals is OK so long as a factor or factors are introduced to give some assurance that these doses are not underpredicted for age groups receiving the highest exposure and that standards are conservatively applied. My feeling is that the uncertainties in our dose estimates are larger than we have admitted, and there may be important factors influencing dose we have not yet taken into account. I find no comfort in the fact that some of the most important foods dose-wise, foods that are known to be a significant part of the diet, are still not yet growing at Enewetak and the radioactivity values used were averages derived from radioactivity concentration ratios involving average plant and soil data that come prir,arily from experience at Bikini. With these concerns in mind I urge that the dose predictions for population groups in this draft be considered the low end Of a range of possible estimates, and that LLNLtS report should give an indication of the high end of the range as well. This could be done by updating the diet used in their 1977 report using Naidu’s food intake levels. Naidu claims these may represent maxi,mum intake, which is what is needed, i.e., the maximum intake for a population group. I think the Naidu numbers can be defended as a conservative “no imports” diet for such a group. Also, I urge that the 250 mrem~year and 4,000 mrem/30 years be recommended to DOI for use in comparing the dose to the highest individuals and to the population with Federal standards in the interest of providing some degree of assurance that the standards will not be exceeded.
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Until there is more substantial evidence the impact of importation of food on use than we have now on of locallv available. food, the levels of the important foods such as pa~danus, breadfruit, an? coconut and its products in the “no imports” diet for the high range estimates should not be reduced by more than a factor of two in devising a diet that contains 50% imported food. Even this may be too much reduction to be able to claim that the doses for the case of use of imported food are conservatively predicted. It would seem contrary to nature for imported foods to selectively reduce intake of local foods that give the highest radioactivity levels, compared to those giving Lower intakes. Further, it would be the first discovery of some phenomenon that makes resettlement within standards easier and not more difficult. I urge that until we have better information on the range of dietary intakes by various groups within a returned population, and on various individuals within such groups, that doses for population groups be multiplied by 5 to obtain doses to the highest individuals in the population. This would help keep the highest doses received in the future from being such a surprise if people return too soon to Eneu, Bikini, or I agree with the draft that further dietary studies are needed, but not that we should rely solely on the MLS diet or on Naidu’s diet for predicting doses at Bikini and Enewetak Atolls at this Office of Health and
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