Health Phys.Abstracts，Volume 119,Number 4

MethodsandFindingsonDietandLifestyleUsedtoSupportEstimationofRadiationDosesfromRadioactiveFalloutfromtheTrinityNuclearTest

Nancy Potischman1,Silvia I.Salazar2,Mary Alice Scott3,Marian Naranjo4,Emily Haozous5,André Bouville6,7,Steven L.Simon6

(1.Office of Dietary Supplements,Office of the Director,National Institutes of Health,Bethesda,MD;2.Office of Communications and Public Liaison,National Cancer Institute,National Institutes of Health,Bethesda,MD;3.Department of Anthropology,New Mexico State University,Las Cruces,NM;4.Special Consultant on Native American communities,Honor Our Pueblo Existence (HOPE),Espanola,NM;5.Pacific Institute for Research and Evaluation:Albuquerque,NM;6.Division of Cancer Epidemiology and Genetics,National Cancer Institute,National Institutes of Health,Bethesda,MD;7.Retired.)

Abstract:The Trinity nuclear test was detonated in south-central New Mexico on 16 July 1945;in the early 2000s,the National Cancer Institute undertook a dose and cancer risk projection study of the possible health impacts of the test.In order to conduct a comprehensive dose assessment for the Trinity test,we collected diet and lifestyle data relevant to the populations living in New Mexico around the time of the test.This report describes the methodology developed to capture the data used to calculate radiation exposures and presents dietary and lifestyle data results for the main exposure pathways considered in the dose reconstruction.Individual interviews and focus groups were conducted in 2017 among older adults who had lived in the same New Mexico community during the 1940s or 1950s.Interview questions and guided group discussions focused on specific aspects of diet,water,type of housing,and time spent outdoors for different age groups.Thirteen focus groups and 11 individual interviews were conducted among Hispanic,White,and Native American participants.Extensive written notes and audio recordings aided in the coding of all responses used to derive ranges,prevalence,means,and standard deviations for each exposure variable for various age categories by region and ethnicity.Children aged 11-15 y in 1940s or 1950s from the rural plains had the highest milk intakes (993 mL d-1),and lowest intakes were among 11- to 15-y-olds in mountainous regions (191 mL d-1).Lactose intolerance rates were 7%-71%,and prevalence was highest among Native Americans.Meat was not commonly consumed in the summer in most communities,and if consumed,it was among those aged 11-15 y of age or older who had relatively small amounts of 100-200 g d-1.Most drinking and cooking water came from covered wells,and most homes were made of adobe,which provided more protection from external radiation than wooden structures.The use of multiple approaches to trigger memory and collect participant reports on diet and other factors from the distant past seemed effective.These data were summarized,and together with other information,these data have been used to estimate radiation doses for representative persons of all ages in the main ethnic groups residing in New Mexico at the time of the Trinity nuclear test.

Keywords:exposure,population;exposure,radiation;intake,radionuclide;internal dose

Health Phys.119(4):390-399;2020

TheMethodologyUsedtoAssessDosesfromtheFirstNuclearWeaponsTest(Trinity)tothePopulationsofNewMexico

André Bouville1,Harold L.Beck2,Kathleen Thiessen3,Owen Hoffman3,Nancy Potischman4,Steven L.Simon1

(1.National Cancer Institute,Bethesda,MD;2.US Department of Energy (retired);3.ORRISK,Oak Ridge,TN)

Abstract:Trinity was the first test of a nuclear fission device.The test took place in south-central New Mexico at the Alamogordo Bombing and Gunnery Range at 05:29 AM on 16 July 1945.This article provides detailed information on the methods that were used in this work to estimate the radiation doses that were received by the population that resided in New Mexico in 1945.The 721 voting precincts of New Mexico were classified according to ecozone (plains,mountains,or mixture of plains and mountains),and size of resident population (urban or rural).Methods were developed to prepare estimates of absorbed doses from a range of 63 radionuclides to five organs or tissues (thyroid,active marrow,stomach,colon,and lung) for representative individuals of each voting precinct selected according to ethnicity (Hispanic,White,Native American,and African American) and age group in 1945 (in utero,newborn,1-2 y,3-7 y,8-12 y,13-17 y,and adult).Three pathways of human exposure were included:(1) external irradiation from the radionuclides deposited on the ground;(2) inhalation of radionuclide-contaminated air during the passage of the radioactive cloud and,thereafter,of radionuclides transferred (resuspended) from soil to air;and (3) ingestion of contaminated water and foodstuffs.Within the ingestion pathway,13 types of foods and sources of water were considered.Well established models were used for estimation of doses resulting from the three pathways using parameter values developed from extensive literature review.Because previous experience and calculations have shown that the annual dose delivered during the year following a nuclear test is much greater than the doses received in the years after that first year,the time period that was considered is limited to the first year following the day of the test (16 July 1945).Numerical estimates of absorbed doses,based on the methods described in this article,are presented in a separate article in this issue.

Keywords:dose assessment;fallout;Trinity test;New Mexico

Health Phys.119(4):400-427;2020

EstimatedRadiationDosesReceivedbyNewMexicoResidentsfromthe1945TrinityNuclearTest

Steven L.Simon1,André Bouville2,Harold L.Beck3,Dunstana R.Melo4

(1.Division of Cancer Epidemiology and Genetics,National Cancer Institute,National Institutes of Health,Bethesda,MD;2.National Cancer Institute,National Institutes of Health,Bethesda,MD (retired);3.New York,NY,US DOE (retired);4.MeloHill LLC,Rockville,MD)

Abstract:The National Cancer Institute study of projected health risks to New Mexico residents from the 1945 Trinity nuclear test provides best estimates of organ radiation absorbed doses received by representative persons according to ethnicity,age,and county.Doses to five organs/tissues at significant risk from exposure to radioactive fallout (i.e.,active bone marrow,thyroid gland,lungs,stomach,and colon) from the 63 most important radionuclides in fresh fallout from external and internal irradiation were estimated.The organ doses were estimated for four resident ethnic groups in New Mexico (Whites,Hispanics,Native Americans,and African Americans) in seven age groups using:(1) assessment models described in a companion paper,(2) data on the spatial distribution and magnitude of radioactive fallout derived from historical documents,and (3) data collected on diets and lifestyles in 1945 from interviews and focus groups conducted in 2015-2017 (described in a companion paper).The organ doses were found to vary widely across the state with the highest doses directly to the northeast of the detonation site and at locations close to the center of the Trinity fallout plume.Spatial heterogeneity of fallout deposition was the largest cause of variation of doses across the state with lesser differences due to age and ethnicity,the latter because of differences in diets and lifestyles.The exposure pathways considered included both external irradiation from deposited fallout and internal irradiation via inhalation of airborne radionuclides in the debris cloud as well as resuspended ground activity and ingestion of contaminated drinking water (derived both from rivers and rainwater cisterns) and foodstuffs including milk products,beef,mutton,and pork,human-consumed plant products including leafy vegetables,fruit vegetables,fruits,and berries.Tables of best estimates of county population-weighted average organ doses by ethnicity and age are presented.A discussion of our estimates of uncertainty is also provided to illustrate a lower and upper credible range on our best estimates of doses.Our findings indicate that only small geographic areas immediately downwind to the northeast received exposures of any significance as judged by their magnitude relative to natural radiation.The findings presented are the most comprehensive and well-described estimates of doses received by populations of New Mexico from the Trinity nuclear test.

Keywords:dose reconstruction;exposure,radiation;fallout;health effects

Health Phys.119(4):428-477;2020

ProjectedCancerRiskstoResidentsofNewMexicofromExposuretoTrinityRadioactiveFallout

Elizabeth K.Cahoon1,Rui Zhang1,Steven L.Simon1,André Bouville2,Ruth M.Pfeiffer1

(1.Division of Cancer Epidemiology &Genetics,National Cancer Institute,National Institutes of Health,Bethesda,MD;2.Retired (NCI/NIH))

Abstract:The Trinity nuclear test,conducted in 1945,exposed residents of New Mexico to varying degrees of radioactive fallout.Companion papers in this issue have detailed the results of a dose reconstruction that has estimated tissue-specific radiation absorbed doses to residents of New Mexico from internal and external exposure to radioactive fallout in the first year following the Trinity test when more than 90% of the lifetime dose was received.Estimated radiation doses depended on geographic location,race/ethnicity,and age at the time of the test.Here,these doses were applied to sex- and organ-specific risk coefficients (without applying a dose and dose rate effectiveness factor to extrapolate from a population with high-dose/high-dose rates to those with low-dose/low-dose rates) and combined with baseline cancer rates and published life tables to estimate and project the range of radiation-related excess cancers among 581,489 potentially exposed residents of New Mexico.The total lifetime baseline number of all solid cancers [excluding thyroid and non-melanoma skin cancer (NMSC)] was estimated to be 183,000 from 1945 to 2034.Estimates of ranges of numbers of radiation-related excess cancers and corresponding attributable fractions from 1945 to 2034 incorporate various sources of uncertainty.We estimated 90% uncertainty intervals (UIs) of excess cancer cases to be 210 to 460 for all solid cancers (except thyroid cancer and NMSC),80 to 530 for thyroid cancer,and up to 10 for leukemia (except chronic lymphocytic leukemia),with corresponding attributable fractions ranging from 0.12% to 0.25%,3.6% to 20%,and 0.02% to 0.31%,respectively.In the counties of Guadalupe,Lincoln,San Miguel,Socorro,and Torrance,which received the greatest fallout deposition,the 90% UI for the projected fraction of thyroid cancers attributable to radioactive fallout from the Trinity test was estimated to be from 17% to 58%.Attributable fractions for cancer types varied by race/ethnicity,but 90% UIs overlapped for all race/ethnicity groups for each cancer grouping.Thus,most cancers that have occurred or will occur among persons exposed to Trinity fallout are likely to be cancers unrelated to exposures from the Trinity nuclear test.While these ranges are based on the most detailed dose reconstruction to date and rely largely on methods previously established through scientific committee agreement,challenges inherent in the dose estimation,and assumptions relied upon both in the risk projection and incorporation of uncertainty are important limitations in quantifying the range of radiation-related excess cancer risk.

Keywords:cancer;fallout;nuclear weapons;radiation risk

Health Phys.119(4):478-493;2020

TheLikelihoodofAdversePregnancyOutcomesandGeneticDisease(TransgenerationalEffects)fromExposuretoRadioactiveFalloutfromthe1945TrinityAtomicBombTest

John D.Boice Jr.1,2

(1.National Council on Radiation Protection and Measurements,Bethesda,MD;2.Vanderbilt University Department of Medicine,Division of Epidemiology,Nashville,TN)

Abstract:The potential health consequences of the Trinity nuclear weapon test of 16 July 1945 at Alamogordo,New Mexico,are challenging to assess.Population data are available for mortality but not for cancer incidence for New Mexico residents for the first 25 y after the test,and the estimates of radiation dose to the nearby population are lower than the cumulative dose received from ubiquitous natural background radiation.Despite the estimates of low population exposures,it is believed by some that cancer rates in counties near the Trinity test site (located in Socorro County) are elevated compared with other locations across the state.Further,there is a concern about adverse pregnancy outcomes and genetic diseases (transgenerational or heritable effects) related to population exposure to fallout radiation.The possibility of an intergenerational effect has long been a concern of exposed populations,e.g.,Japanese atomic bomb survivors,survivors of childhood and adolescent cancer,radiation workers,and environmentally exposed groups.In this paper,the likelihood of discernible transgenerational effects is discounted because (1) in all large-scale comprehensive studies of exposed populations,no heritable genetic effects have been demonstrated in children of exposed parents;(2) the distribution of estimated doses from Trinity is much lower than in other studied populations where no transgenerational effects have been observed;and (3) there is no evidence of increased cancer rates among the scientific,military,and professional participants at the Trinity test and at other nuclear weapons tests who received much higher doses than New Mexico residents living downwind of the Trinity site.

Keywords:epidemiology;fallout;health effects;nuclear weapons

Health Phys.119(4):494-503;2020

AccountingforUnfissionedPlutoniumfromtheTrinityAtomicBombTest

Harold L.Beck1,Steven L.Simon2,André Bouville3,Anna Romanyukha4

(1.US DOE Environmental Measurements Laboratory (retired);2.Divison of Cancer Epidemiology,National Cancer Institute;3.National Cancer Institute (retired);4.Centre for Medical Radiation Physics,School of Physics,University of Wollongong,Wollongong,NSW,Australia)

Abstract:The Trinity test device contained about 6 kg of plutonium as its fission source,resulting in a fission yield of 21 kT.However,only about 15% of the239Pu actually underwent fission.The remaining unfissioned plutonium eventually was vaporized in the fireball and after cooling,was deposited downwind from the test site along with the various fission and activation products produced in the explosion.Using data from radiochemical analyses of soil samples collected postshot (most many years later),supplemented by model estimates of plutonium deposition density estimated from reported exposure rates at 12 h postshot,we have estimated the total activity and geographical distribution of the deposition density of this unfissioned plutonium in New Mexico.A majority (about 80%) of the unfissioned plutonium was deposited within the state of New Mexico,most in a relatively small area about 30-100 km downwind (the Chupadera Mesa area).For most of the state,the deposition density was a small fraction of the subsequent deposition density of239+240Pu from Nevada Test Site tests (1951-1958) and later from global fallout from the large US and Russian thermonuclear tests (1952-1962).The fraction of the total unfissioned239Pu that was deposited in New Mexico from Trinity was greater than the fraction of fission products deposited.Due to plutonium being highly refractory,a greater fraction of the239Pu was incorporated into large particles that fell out closer to the test site as opposed to more volatile fission products (such as137Cs and131I) that tend to deposit on the surface of smaller particles that travel farther before depositing.The plutonium deposited as a result of the Trinity test was unlikely to have resulted in significant health risks to the downwind population.

Keywords:239Pu;fallout;nuclear weapons;plutonium

Health Phys.119(4):504-516;2020