Fallout Radiation Research Articles

Childhood leukaemia in Great Britain and fallout from nuclear weapons testing

The possible effects of radiation from fallout on childhood leukaemia mortality from 1950 to 1987 and registrations from 1963 to 1987 were assessed using a division of Great Britain into regions with higher rainfall and a consequently higher fallout radiation dose in the 1960s and regions with lower rainfall and a lower radiation dose. Childhood leukaemia mortality rates declined and registration rates increased throughout the period. For ages 0-14 years, the differences between rates in wet regions and dry regions were small and appeared unrelated to periods of low, medium and high radiation exposure based on dose equivalent to the red bone marrow after birth. For the 0-4 years age group the highest ratios of leukaemia death rates and registration rates in the wet compared with the dry part of Great Britain occurred in the period of highest radiation exposure after birth. The death rate ratio was significantly raised in the period of high exposure compared with the surrounding medium exposure periods, but the difference in registration rate ratios between the high exposure period and the medium exposure period following was not statistically significant. The results might be explained by survival and registration changes, or chance in the case of registrations, but do not exclude the possibility that low doses of radiation from fallout were responsible for an increased risk of leukaemia in young children in Great Britain.

Trends and Geographical Distribution of Childhood Leukemia in Greece in Relation to the Chernobyl Accident

Parts of Greece have been exposed to fallout radiation from the Chernobyl accident as much as any of the countries boardering with the former Soviet Union, because of the direction of the prevailing winds after the accident. Although fallout radiation did not reach levels expected to be associated with measurable effects, there is widespread concern in Greece that the incidence of childhood leukemia may be rising in the more heavily affected parts of Greece. Patient discharge data from all Greek hospitals treating childhood leukemia were used to calculate the annual incidence of the disease from January 1980 to June 1986 (preaccident period), from July 1986 to June 1988 (immediate postaccident period) and from July 1988 to June 1991 ("relevant" post-accident period, that accommodates the presumed latent period of the disease). Fallout radiation measurements (in Bq/kg Cs-137) were used to create 17 regions of similar (within regions) but highly variable (between regions) levels of fallout deposition. Background radiation (in Bq/kg Ra-226) and annual incidence of childhood leukemia by region were also estimated. There was no evidence of increased incidence of childhood leukemia during the immediate or the "relevant" post-Chernobyl period in any part of the country. Furthermore, regression analyses did not show any significant or suggestive association of childhood leukemia by region with either background or fallout radiation. These results indicate that the Chernobyl accident did not affect noticeably the incidence of childhood leukemia in Greece during the five-year post accident period.

Thermoluminescence Measurements of Gamma-ray Doses Attributable to Fallout from the Nevada Test Site Using Building Bricks As Natural Dosimeters

During the 1950's, the U.S. Government conducted an intensive atmospheric nuclear testing program in Nevada. Fallout from these atmospheric tests was measured throughout the U.S. with some of the heaviest concentrations to populated areas falling east of the test site in Washington County, UT. External exposures from 6.5 x 10(-4) C kg-1 to 26 x 10(-4) C kg-1 (2.5-5.0 R) were reported for this region. This study provides an independent measurement of fallout radiation doses to selected communities in Utah using a thermoluminescence technique originally developed for the dating of ancient pottery. The application of the predose thermoluminescence technique to fallout dosimetry is described. A mean dose of 38 +/- 15 mGy (4.4 +/- 1.7 R), attributed to fallout radiation, was measured in quartz grains extracted from the outer centimeter of bricks removed from six communities in Washington and Kane Counties in Utah.

Whole Body Counters in Biomedical Research

Whole body counter plays an important role in medical diagnosis and clinical research. It has been used for monitoring of radiation workers for the assessment of internal contamination or assessment of activity in persons exposed to radiation fallout. In a nuclear emergency like Chernobyl, neutron exposure to the radiation victims was assessed by measuring the induced activity of /sup 24/Na. Apart from its use in determining certain element composition in the body, it has got a number of clinical applications like absorption tests, and metabolic and kinetic studies. The work done at INMAS whole body counter facility is also discussed.

Thyroid cancer epidemiology in England and Wales: time trends and geographical distribution.

Thyroid cancer incidence has been increasing in many countries, whereas mortality has been falling due to better survival. Radiation is the best-established risk factor and there has been concern that recent rises in incidence might be related to fallout radiation from atmospheric nuclear weapon tests. We examined thyroid cancer time trends and geographical distribution in England and Wales and possible interpretations of these. During 1962-84, there were significant increases in incidence (P < 0.001) in each sex at ages under 45. Cohort analysis by single year of birth showed an overall increase in incidence risks in women aged 0-44 born since 1920, with a sudden rise in risk for the birth years 1952-55 followed by a lower risk for the more recent cohorts. In men, there was an overall increase in risk at ages 0-44 in successive birth cohorts, but the pattern was irregular. In each sex, the risk in persons aged 45 and over decreased slightly in successive generations. Geographically, highest incidence risks were in countries in North and Mid Wales, in which the risk was almost twice that in the rest of the country. This pattern was present only at ages 45 and over and was most clear in rural areas. The peak of thyroid cancer risk in women born in 1952-55 is consistent with a carcinogenic effect of fallout radiation, since these women were children in the late 1950s and early 1960s when fallout radiation was greatest in England and Wales. The focus of high thyroid cancer risks in Wales was in areas with high levels of fallout radiation. However, thyroid cancer risks in Wales were not high for more recent cohorts (the ones who were exposed to fallout early in life), and a focus on high risk of benign thyroid diseases was present in Wales well before nuclear weapons existed. The distributions of these benign thyroid diseases, or of factors causing them, seem more likely than fallout to explain the high risk areas for thyroid cancer in the country.

The accident at Chernobyl and trisomy 21 in Finland.

Our objective was to explore whether the radiation fallout in Finland after the accident at the Chernobyl nuclear power plant in April 1986 led to an increased incidence of trisomy 21. In this geographic and temporal cohort study, the country was divided into three zones according to the amounts of radioactive fallout and internal radiation caused by two cesium isotopes. The 518 cytologically verified cases of trisomy 21 were divided into a control group (conceived before the accident), and a study group of children whose expected dates of birth were in the post-accident years 1987-1988, i.e., pregnancies commenced after May 1986. The cases were also divided into three subgroups according to the zones of radiation. There were no significant differences in prevalence of trisomy 21 between the control and study groups nor between the three zones in spite of the significant differences in the levels of radiation and in the body burden that prevailed throughout the study period. Power estimates showed that in the two zones of lower radiation, an increase of 0.5% in the prevalence would have been detected with a power of 0.85, and in the somewhat smaller zone of the highest radiation, with a power of 0.70. The study lends no further support to the view that the low radiation fallout in western Europe would have been causally associated with trisomy 21.

Early-developmental exposure to nuclear fallout radiation: interpretive considerations for epidemiological studies of violent death.

Significant positive correlations have been found between the proportion of the US population constituted by 15- to 24-yr.-olds and incidence of homicide and suicide deaths in this age group. Holinger, Offer, and Ostrov recently proposed explanations of these findings at three conventional conceptual levels: (a) the epidemiological-sociologic, (b) the psychodynamic-clinical, and (c) the nosological. Based on recent exploratory data, a fourth, distinctively unconventional, alternative is suggested here for consideration in multivariate, epidemiological studies of violent death, namely, the possible effects due to early-developmental exposure to toxic radiation.

Early exposure to toxic radiation and violent death: a comment.

Suicide now ranks among the leading causes of death in the United States and Canada. Furthermore, in the States the homicide rate has become a matter of concern (5, 6). The increasing incidence of these problems has preoccupied many researchers and considerable efforts have been made to identify et1ologlc31 factors. Virtually no stone has been left unturned. Variables studied ranged from birthdays ( I ) , death anniversary reactions (2), and moon phases (3), to gross national product per capita and the proportion of females in the labor force (4). Recently Pellegrini (7) suggested yet another variable lor consideration. His biogenic hypothesis states that a predisposition to suicidal and homicidal behavior may have been induced in individuals who during their early development have been exposed to toxic radiation fallout from above ground detonation of nuclear weapons. The author does not provide empitical data in support of the hypothesis but proposes that toxic radiation is a factor worthy of consideration in multivariate analytic inquiry into the complex epidemiology of violent death. Although i t is an interesting proposition, I fear that the researcher who accepts the challenge of inves~igating this hypothesis will encounter considerable difficulties. First, there will be the methodological problem of identifying and assessing the population under consideration. Second, assuming that one regards the effect of radiation as a biological correlate, the heterogeneity of the target populations and the overlap of the violent behaviors and illnesses such as depression will make it difficult to obtain significant and replicable correlations between the behaviors in question and the possible biological factor(s). Third, risk factors with a low or moderate specificity such as toxic radiation, when applied to events with low base rates such as suicide and homicide, will inevitably result in high numbers of 'false positives.' Finally, it appears that exposure to toxic radiation is merely a proxy variable for more fundamental processes, processes that are already subject to investigations by other researchers. I suggest that more d i r e c ~ evaluations of neurochemical, biochemical, genetic, and social-psychological factors as part of a multidimensional approach to the causal explanation of suicide and homicide will lead to more fruitful results.

The risks of radiation

The risks of radioactivity are a really complicated matter, yet they are much better known than are the risks relating to thousands of chemical poisons that occur in our environment. The greatest mistakes are probably made in the definition of safety margins. Except for the bombs dropped in Japan and one other case in the Marshall Islands, there has always—luckily—been a wide safety margin between fallout radiation and doses dangerous to health; the margin has actually been about 1000-fold. The Chernobyl dose of 0.5 mGy/year that we received is only 1/1000 of the acute dose of 0.5 Gy which would cause a slight and nonpermanent change in the blood picture.

Chernobyl retrospective

On April 28, 1986 heavy radioactive fallout from an unknown source was reported from Sweden. Later, it was discovered that two days earlier, a nuclear power reactor at Chernobyl, in the Soviet Union, had exploded releasing an enormous cloud of effluent containing 40 million Ci of 131I, 3 million Ci of 137Cs, and 50 million Ci of xenon radioisotopes. This far exceeded the 15 Ci of 131I escape in the notorious Three Mile Island accident. Chernobyl reactor IV, of an antiquated design, was a graphite-moderated reactor which suffered a steam explosion when the operating staff attempted an experiment involving preservation of safety functions during a planned shutdown. Following the explosion, a fire started in the graphite core which required ten days to control. Thirty-one persons died, two in the initial explosion and 29 of various combinations of thermal and radiation burns, and gamma irradiation. Existing emergency plans were invoked involving treatment on the scene and evacuation of seriously injured patients to a special hospital in Moscow, as well as to nearby Kiev. Later, 135,000 residents of the immediate neighborhood were surveyed and evacuated after fallout radiation levels began to rise. Fallout patterns around Europe and the northern hemisphere were closely tracked. Consequences of the accident in human and monetary terms will require years of evaluation. Although the United States has no power reactors of the Chernobyl type, the country does have a radiation disaster management plan, often rehearsed at the state level. As a consequence of Chernobyl certain international agreements dealing with radiation disaster information and management have been forged.

Civil defence against nuclear attack: An evaluation of one local plan

In order to assess the value of civil defence planning for a nuclear attack, this paper focuses on a specific local example—the official civil defence plan of Pitt County, North Carolina, USA. Pitt County has been designated a host area in which all of its 90 000 residents and 75 000 evacuees from neighbouring target areas are to be sheltered. After a brief review of this plan, three crucial questions are considered: (1) Will the evacuees designated for shelter in Pitt County arrive? (2) Will county officials be able to provide for the needs of the sheltered population? (3) If the population is sheltered as planned, will they survive a nuclear war? Doubts are expressed about whether each of these goals could be achieved. For example, it is estimated that 13.5 per cent of persons in shelters would be exposed to lethal doses of fallout radiation, but the plan makes no mention of the danger of acute radiation sickness. In view of the serious weaknesses identified in the plan, the paper concludes that efforts...

Suicide and homicide in the United States: an epidemiologic study of violent death, population changes, and the potential for prediction

The authors found significant positive correlations between the suicide and homicide rates for 15-24-year-olds and the proportion of 15-24-year-olds in the U.S. population from 1933 to 1982. Significant negative correlations were found for most adult age groups (35-64 years). Since future numbers of adolescents and adults can be estimated on the basis of current population data for children and preadolescents, the epidemiologic patterns for suicide and homicide may be predictable for certain age groups. However, methodologic problems are inherent in using national mortality and population data, and many years are necessary to evaluate such epidemiologic propositions.

Radioactive iodine-131 over Taiwan after the Chernobyl accident

Two weeks after the Chernobyl Nuclear Power Plant accident, a substantial increase in radioactivity above normal background levels was observed in various samples taken in Taiwan, R. O. C., which is 7600 km from Chernobyl. The131I concentrations in grass, rainwater, and milk were monitored continuously in succeeding weeks and correlations with weather conditions are discussed. Levels of radiation fallout over Taiwan due to the Chernobyl accident are much lower than the response levels recommended by local authorities and pose no danger to the public.

Pituitary Tumors Following Fallout Radiation Exposure

Two pituitary tumors were diagnosed in a small population of Marshallese accidentally exposed to radioactive fallout in 1954.

Pituitary tumors following fallout radiation exposure

Two pituitary tumors were diagnosed in a small population of Marshallese accidentally exposed to radioactive fallout in 1954. Endocrinologic findings in the exposed population, are reported and the possible relation of the tumors to radiation exposure and thyroid disease is discussed.

A new fallout prediction model.

The standard method for the calculation of nuclear weapon fallout radiation doses and dose rates in operational type studies for the last 20 yr has been the computer algorithm known as WSEG-10. WSEG-10 uses empirical functions rather than numerical analyses and computes fallout dose (rates) in seconds or less on modern computers. WSEG-10 has long been criticized for its inability to allow for variations in the activity-particle size distribution of the fallout, for its inability to account for fractionation and for the absence of realistic settling rates. At the other end of the scale, the Defense Land Fallout Information Code, DELFIC, is currently used for research work and as a comparison standard. DELFIC produces fallout footprints on the ground by numerical integration, employing discrete cells in space, time and particle size. A new fallout prediction method is presented here which, unlike WSEG-10, does allow variations in activity with particle size, does account for fractionation and does model variable settling rates. This new model, like WSEG-10 but unlike DELFIC, computes in seconds or less. Some results are presented and compared to DELFIC and to WSEG results. Additionally, this new model will treat the far-field problem of interest in a massive strategic attack which cannot be easily done using DELFIC.

Acute Myelogenous Leukemia Following Fallout Radiation Exposure

ACUTE myelogenous leukemia developed in a 19-year-old Marshallese man who had been exposed to radioactive fallout at 1 year of age. He was one of 64 people on Rongelap Island accidentally exposed in 1954 following the testing of an atomic device on Bikini atoll 100 miles away. The acute effects of exposure on this population were hematological depression from total body exposure to gamma radiation of 175 rads and beta-ray burns and epilation from deposit of fallout on the skin. There were no deaths, and recovery occurred within a year. Internal absorption of radionuclides from inhalation and consumption of contaminated food and water produced no acute effects, but absorption of radioactive iodine resulted in later development of thyroid lesions in one third of the population; three of these lesions were malignant. The highest incidence was in children exposed at less than 10 years of age, some of whom had growth

Acute myelogenous leukemia following fallout radiation exposure

Acute myelogenous leukemia following fallout radiation exposure

Aircrew Vulnerability in Nuclear Encounters

Abstract : A computational method (algorithm) is described which estimates probable mission outcome resulting from crew exposure to prompt neutron gamma radiation and/or residual fallout radiation. The threat scenario presupposes that:the crew has encountered one or more nuclear weapons; both aircraft and crew have survived the blast and thermal insults; and the aircraft is undegraded by the radiation (aircraft is survivable). Thus one is examining decreases in mission performance based upon crew irradiation only.

Automatic Radioactive Inventory System

The philosophy used in detector configuration design and small computer programming for an Automatic Radioactive Inventory System is presented. The range of application is nondestructive, low-density energy analysis from natural and fallout radiation in soils to high-level radiation in solid waste packages.