Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “RADIOACTIVE FALLOUT”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 217 records · Page 12Linked to original sources
PubMed2000

High incidence of micronuclei in lymphocytes from residents of the area near the Semipalatinsk nuclear explosion test site.

The Semipalatinsk area is highly contaminated with radioactive fallout from 40 years of continuous nuclear testing. The biological effects on human health in this area have not been studied. Significant remaining radioactivities include long-lived radioisotopes of 238,239,400Pu, 137Cs and 90Sr. To evaluate the long-term biological effects of the radioactive fallout, the incidence of micronuclei in lymphocytes from residents of the area was observed. Blood was obtained from 10 residents (5 females and 5 males, aged 47 to 55 years old) from each of the 3 areas of Znamenka, Dolon and Semipalatinsk, which are about 50-150 km from the nuclear explosion test site. For micronucleus assay, PHA-stimulated lymphocytes were cultured for 72 h and cytochalasin B was added at 44 h for detecting binuclear lymphocytes. Five thousand binuclear lymphocytes in each resident were scored. The means of micronucleus counts in 1,000 lymphocytes in residents of Semipalatinsk, Dolon and Znamenka were 16.3, 12.6, and 7.80, respectively, which were higher than those of the normal Japanese persons (4.66). These values were equivalent to the results obtained from 0.187-0.47 Gy of chronic exposure to gamma-rays at a dose rate of 0.02 cGy/min. The high incidence of micronuclei in residents of the Semipalatinsk nuclear test site area was mainly caused by internal exposure rather than external exposure received for the past 40 years.

Bone Marrow↗
PubMed1978

Environmental radioactivity in the Faroes in 1977.

Measurements of fallout radioactivity in the Faroes in 1967 are presented. Strontium-90 (and 137Cs in most cases) was determined in regularly collected samples of precipitation, grass, milk, fish, sea water, bread, and drinking water. In addition, analyses were made of spot samples of lamb, sea birds, potatoes, sea plants, vegetables, eggs, and human bone. Estimates are given of the mean contents of 90Sr and 137Cs in the human diet in the Faroes in 1977.

Adult↗
PubMedDate not supplied

Consequences of the nuclear power plant accident at Chernobyl.

The Chernobyl Nuclear Power Plant accident, in the Ukrainian Soviet Socialist Republic (SSR), on April 26, 1986, was the first major nuclear power plant accident that resulted in a large-scale fire and subsequent explosions, immediate and delayed deaths of plant operators and emergency service workers, and the radioactive contamination of a significant land area. The release of radioactive material, over a 10-day period, resulted in millions of Soviets, and other Europeans, being exposed to measurable levels of radioactive fallout. Because of the effects of wind and rain, the radioactive nuclide fallout distribution patterns are not well defined, though they appear to be focused in three contiguous Soviet Republics: the Ukrainian SSR, the Byelorussian SSR, and the Russian Soviet Federated Socialist Republic. Further, because of the many radioactive nuclides (krypton, xenon, cesium, iodine, strontium, plutonium) released by the prolonged fires at Chernobyl, the long-term medical, psychological, social, and economic effects will require careful and prolonged study. Specifically, studies on the medical (leukemia, cancers, thyroid disease) and psychological (reactive depressions, post-traumatic stress disorders, family disorganization) consequences of continued low dose radiation exposure in the affected villages and towns need to be conducted so that a coherent, comprehensive, community-oriented plan may evolve that will not cause those already affected any additional harm and confusion.

Accidents↗
PubMed2001

A critical review of measures to reduce radioactive doses from drinking water and consumption of freshwater foodstuffs.

Following a radioactive fallout event, there are a number of possible intervention measures to reduce radioactive doses to the public via the surface water pathway. We have critically reviewed the options available to decision-makers in the event of radioactive contamination of surface waters. We believe that the most effective and viable measures to reduce radioactivity in drinking water are those which operate at the water treatment and distribution stage. Intervention measures to reduce concentrations of radioactivity in rivers and reservoirs are expected to be much less viable and efficient at reducing doses via the drinking water pathway. Bans on consumption of freshwater fish can be effective, but there are few viable measures to reduce radioactivity in fish prior to the preparation stage. Lake liming and biomanipulation have been found to be ineffective for radiocaesium, although the addition of potassium to lakewaters appears promising in some situations. Lake liming may be effective in reducing radiostrontium in fish, though this has not, to our knowledge, been tested. De-boning fish contaminated by strontium is probably the most effective food preparation measure, but salting and freezing can also reduce radiocaesium concentrations in fish. The provision of accurate information to the public is highlighted as a key element of countermeasure implementation.

Animals↗
PubMed1992

Arctic terrestrial ecosystem contamination.

Limited data have been collected on the presence of contaminants in the Arctic terrestrial ecosystem, with the exception of radioactive fallout from atmospheric weapons testing. Although southern and temperate biological systems have largely cleansed themselves of radioactive fallout deposited during the 1950s and 1960s, Arctic environments have not. Lichens accumulate radioactivity more than many other plants because of their large surface area and long life span; the presence and persistence of radioisotopes in the Arctic is of concern because of the lichen----reindeer----human ecosystem. Effective biological half-life of cesium 137 is reckoned to be substantially less than its physical half-life. The database on organochlorines in Canadian Arctic terrestrial mammals and birds is very limited, but indications are that the air/plant/animal contaminant pathway is the major route of these compounds into the terrestrial food chain. For terrestrial herbivores, the most abundant organochlorine is usually hexachlorobenzene followed by hexachlorocyclohexane isomers. PCB accumulation favours the hexachlorobiphenyl, pentachlorobiphenyl and heptachlorobiphenyl homologous series. The concentrations of the various classes of organochlorine compounds are substantially lower in terrestrial herbivore tissues than in marine mammal tissues. PCBs and DDT are the most abundant residues in peregrine falcons (a terrestrial carnivore) reaching average levels of 9.2 and 10.4 micrograms.g-1, respectively, more than 10 times higher than other organochlorines and higher than in marine mammals, including the polar bear. Contaminants from local sources include metals from mining activities, hydrocarbons and waste drilling fluids from oil and gas exploration and production, wastes from DEW line sites, naturally occurring radionuclides associated with uranium mineralization, and smoke containing SO2 and H2SO4 aerosol from the Smoking Hills at Cape Bathurst, N.W.T.

Animals↗
PubMed2003

Iodine prophylaxis around the Semipalatinsk Nuclear Testing Site, Republic of Kazakstan.

OBJECTIVE: This study aimed to clarify the iodine deficiency status in the Semipalatinsk region that has been contaminated by radioactive fallout from nuclear testing during the period of the former USSR. DESIGN: Based on the Japan-Kazakstan joint project of adult cancer screening around the Semipalatinsk Nuclear Testing Site (SNTS), from May to October 2002 spot urine specimens were collected at random in each village. Separately, children aged 5-15 years from around the SNTS were chosen at random and spot urine specimens were collected from them. SETTING: Area contaminated by radioactive fallout around the SNTS, Republic of Kazakstan. SUBJECTS: A total of 2609 adults aged >40 years from 16 settlements in three regions and one city, and 298 children aged 5-15 years from two regions and one city. RESULTS: Median urinary iodine concentrations of adults and children in all regions were in the range of 116.0-381.7 and 127.7-183.0 microg l(-1), respectively. The highest prevalence of values <50 microg l(-1) (14.1%) did not exceed 20%. Distributions within each group, adults and children, showed almost the same pattern, except for one region where more than 50% of adults had urinary iodine concentration >100 microg l(-1). CONCLUSIONS: In agreement with our previous studies, the urinary iodine concentration data showed no clear evidence of iodine deficiency around the SNTS. Kazakstan is geographically and nutritionally at moderate risk of iodine deficiency disorders without fortification or iodine replacement by iodised salt. The socio-medical prophylaxis against iodine deficiency has been successfully maintained in East Kazakstan.

Adolescent↗
PubMed1989

The accident at Chernobyl and outcome of pregnancy in Finland.

OBJECTIVE: To evaluate the outcome of pregnancy in Finnish women after the accident at the Chernobyl nuclear power plant on 26 April 1986. DESIGN: Geographic and temporal cohort study. SETTING: Finland divided into three zones according to amount of radioactive fallout. SUBJECTS: All children who were exposed to radiation during their fetal development. Children born before any effects of the accident could be postulated--that is, between 1 January 1984 and 30 June 1986--served as controls. INTERVENTIONS: Children were divided into three temporal groups: controls, children who were expected to be born in August to December 1986, and children who were expected to be born in February to December 1987. They were also divided, separately, into three groups according to the three geographic zones. END POINT: Incidence of congenital malformations, preterm births, and perinatal deaths. MEASUREMENTS AND MAIN RESULTS: There were no significant differences in the incidence of malformations or perinatal deaths among the three temporal and three geographic groups. A significant increase in preterm births occurred among children who were exposed to radiation during the first trimester whose mothers lived in zones 2 and 3, where the external dose rate and estimated surface activity of caesium-137 were highest. CONCLUSIONS: The results suggest that the amount of radioactive fallout that Finnish people were exposed to after the accident at Chernobyl was not high enough to cause fetal damage in children born at term. The higher incidence of premature births among malformed children in the most heavily polluted areas, however, remains unexplained.

Abnormalities, Radiation-Induced↗
PubMed1999

Two cases of thyroid cancer in a small workforce.

In 1994, in a large parcel depot in the north of England employing 600 staff and 24 electrical and mechanical engineers, two engineers developed papillary cell carcinoma of the thyroid in the same year. A comprehensive review of the literature revealed that ionizing radiation is the only known direct cause of this disease. There was speculation that air filter changing undertaken by the two men affected, shortly after the Chernobyl accident in 1986, may have exposed them to concentrated radioactive fallout. A radiation survey of the parcel depot was undertaken and revealed no evidence of abnormal radioactivity. A total of 27 past and present engineering staff were screened for thyroid cancer. No cases of thyroid cancer were found. Investigation of clusters of rare disease in the occupational setting is indicated mainly in order to address the concerns of the workforce. Nevertheless, investigation is warranted, especially when the aetiology of a disease is poorly understood. It would be prudent for doctors, in whatever speciality, to take an occupational history from individuals who develop thyroid cancer.

Carcinoma, Papillary↗
PubMed2001

[Medical and demographic evaluation of public health under the prolonged impact of specific ecological influences].

The materials represented cover medical and demographic study of public health state in Altai area, under prolonged exposure of certain populations to radioactive fallout due to nuclear testing at Semipalatinsk ground. The authors specified a method for retrospective medical and demographic diagnosis of the residents exposure to radioactive fallout caused by nuclear testing, for evaluation of consequent damage to public health.

Demography↗
PubMed2002

Individual dose reconstruction among residents living in the vicinity of the Semipalatinsk nuclear test site using EPR spectroscopy of tooth enamel.

Individual accumulated doses were determined by EPR spectroscopy of tooth enamel for 26 adult persons residing in territories adjacent to the Semipalatinsk Nuclear Test Site (SNTS). The absorbed dose values due to radiation from nuclear tests were obtained after subtracting the contribution of natural background radiation from the total accumulated dose. The determined dose values ranged up to 250 mGy, except for one person from Semipalatinsk city with a measured dose of 2.8 +/- 0.4 Gy. Increased dose values were determined for the individuals whose teeth were formed before 1962, the end of the atmospheric nuclear tests. These values were found to be significantly larger than those obtained for a group of younger residents of heavily exposed territories and the residents of territories not exposed to radioactive fallout. These increased dose values are consistent with those based on officially registered data for the Northeastern part of Kazakstan adjacent to SNTS, which was exposed to high levels of radioactive fallout from nuclear tests in period 1949-1962.

Adult↗
PubMed1994

Pregnancy outcome in Sweden after the Chernobyl accident.

OBJECTIVE: To study pregnancy outcome including development of childhood cancer in areas within Sweden with the highest radioactive fallout after the Chernobyl accident in 1986. METHODS: Various Swedish health registries were used in order to identify all pregnancies and their outcome in Sweden according to the measured radioactive fallout. RESULTS: A reduction in conception rate occurred after the accident, as well as possible increase in induced abortion rate during the fall after the accident. No changes in the rate of spontaneous abortions or congenital malformations occurred in pregnancies exposed at the time of the accident. There was a temporary increase in low birth weight which could well be random. Among infants conceived after the accident, a slight excess of Down syndrome infants was found in the most exposed areas but this observation is based on small numbers. No certain excess of childhood cancer was seen in the most exposed areas, but three infants, in utero at the time of the accident, developed leukemia. CONCLUSIONS: No major effects on pregnancy outcome were seen but the indicated increase in Down syndrome and childhood leukemia--if not random--could be a result of radioactive exposure.

Abortion, Spontaneous↗
PubMed1996

Yearly variation of spontaneous somatic mutation frequency in the stamen hairs of Tradescantia clone KU 9 grown outdoors, which showed a significant increase after the Chernobyl accident.

Scoring of spontaneous somatic pink mutation frequency in the stamen hairs of Tradescantia clone KU 9, a heterozygote for flower color (blue/pink; the blue color being dominant), was carried out for 11 years on plants grown outdoors, during the period of May 11-31 (for 3 weeks) in every year from 1982 to 1992. Weekly and yearly variations of the spontaneous mutation frequency were observed, and such variations could mostly be correlated to the difference in temperature. That is, the mutation frequency was generally higher in the weeks and years when the temperature was relatively low, showing the strongest negative correlation with the average minimum temperature. The variations were also correlated to the diurnal temperature difference, the mutation frequency being higher with larger diurnal temperature difference in general. However, the mutation frequency observed in 1986 was exceptionally higher than that expected from the temperature for this year, and was very significantly higher than for other years. The scoring of mutation frequency was thus continued in 1986 for an additional 4 weeks (June 1-28), and it was confirmed that such higher mutation frequencies lasted for 6 weeks in total. The exceptionally high mutation frequency seemed to be related to the radioactive fallout which occurred in early to mid May of 1986, even in Japan, after the serious nuclear reactor accident at Chernobyl, and also to the biological concentrations of radioactive nuclides which subsequently occurred, although it was difficult to conclude this definitely. The mutation frequency in 1987 was second highest, and was also significantly higher than the lowest mutation frequency observed in 1990.

Climate↗
PubMed2004

Processes, dynamics and modelling of radiocaesium cycling in a chronosequence of Chernobyl-contaminated Scots pine (Pinus sylvestris L.) plantations.

In a large forested area affected by the Chernobyl radioactive fallout, especially in CIS, the lasting recycling of radiocaesium (137Cs) by the trees is a source of long-term contamination of woody products. The quantitative description of the 137Cs dynamics in contaminated forest is a prerequisite to predictive modelling and further management of such territories. Three even-aged mono-specific Scots pine stands (17, 37 and 57 years old) were selected in a contaminated woodland in southeastern Belarus to constitute an adequate chronosequence. We determined the potassium and radiocaesium annual fluxes involved in the biological cycling in each stand using a well-documented calculation methodology. Qualitatively, 137Cs was shown to be rapidly recycled in trees through the same pathways as K and to redistribute similarly between the tree components. Compared to K, a higher fraction of 137Cs, corresponding to about the half of the annual uptake, is immobilised in perennial organs. With tree development, trunk wood and bark become prevailing sinks for 137Cs since they represent an increasing pool of biomass. In the pine chronosequence, the current root absorption, respectively, mobilizes 0.53, 0.32 and 0.31% year(-1) of the total 137Cs pool in soil. Variations in the 137Cs uptake do not reflect differences in the 137Cs balance between stands. In the two older stands, 51 and 71% of the current tree contamination are related to earlier accumulation subsequent to the initial fallout interception and recycling. The soil is the dominant source of long-term tree contamination. A simple modelling based on the measured 137Cs fluxes indicates that, for young stands, radioactive decay-corrected contamination would stabilize after reaching a maximum of 25 years after the 137Cs deposition. Stemwood presents a maximum of 15 years after the deposition and decrease afterwards mainly through radioactive decay. In the older stands, the decontamination is constant without local maximum of 137Cs level in the wood. The 137Cs contamination of tree components is the result of different influential processes like root uptake, internal translocation and immobilisation. For more accurate predictions, the calibration of existing models would be benefited by comparing with the 137Cs annual fluxes instead of the simple transfer factor coefficients. In the perspective of other applications, there is a need of such data for other radionuclides as well as for heavy metals.

Calibration↗
PubMed1999

[Facial cleft birth rate in former East Germany before and after the reactor accident in Chernobyl].

Cleft lip palates (CLP) are caused by a variety of factors. Ionizing radiation is only one of these factors. The meltdown of the nuclear reactor at Chernobyl on April 26, 1986, and the subsequent radioactive fallout did not cause any acute radiation sickness in Germany. Nevertheless, in West Berlin a significant increase of trisomy-21 cases was reported in births 9 months after the Chernobyl reactor accident. In our study we analyzed the influence of the radioactive fallout after the Chernobyl disaster on the rate and regional distribution of CLP newborns in the former German Democratic Republic (GDR). In contrast to the Federal Republic of Germany an ongoing malformation register for CLP newborns had existed in the former GDR since 4 July 1967. Environmental data were collected from national and international environmental authorities and atomic energy agencies. Population statistics were taken from the statistical year-book of the former GDR. During a 10-year period from 1980 to 1989, the average number of CLP newborns in the GDR was 1.88 per 1,000 live births. A significant prevalence increase was recorded in 1983, 1987 und 1988. In comparison to the mean rate in the period from 1980 until 1986, 1987 demonstrated an increase of 9.4%. Regional prevalence increases were seen in the three northern districts of Schwerin, Rostock and Neubrandenburg, where the radioactivity measurements in general showed higher levels of the radionuclides caesium-137 und strontium-90 than in other districts. Owing to the comprehensive malformation register for CLP patients in the GDR, this is the first study for Germany, analyzing the CLP rate before and after the fallout in Chernobyl. The results support the allegation of the influence of radiation-induced increase of CLP newborns after the Chernobyl reactor accident.

Abnormalities, Radiation-Induced↗
PubMed2001

Radiological impact in Greece of the Chernobyl accident--a 10-y retrospective synopsis.

The present study summarizes the published results of the studies of the Environmental Radioactivity Laboratory on the radiological impact in Greece of the Chernobyl nuclear accident. Some unpublished data from personal communications also have been used to present the time evolution of the studies. The radiological impact in Greece of the Chernobyl accident is examined in two separate phases: that of the acute effects and that of the delayed effects. Some measurements cover the whole period from the accidental pollution to the return to pre-accident levels and are used for estimations of ecological half-lives. The composition of radioactive fallout is examined, and the integrated concentrations of the principal radionuclides in the fallout are presented. The variations in the air concentrations of certain radionuclides and those of the gamma-ray intensity are presented as well. Some results from the study of hot particles detected during the acute phase are also given. The radioactive contamination of abiotic environmental components, food, and crops during the acute and the delayed effects phases are discussed in relation to the radiological impact on the population.

Air Pollution, Radioactive↗
PubMed2001

RET/PTC rearrangements in thyroid nodules: studies in irradiated and not irradiated, malignant and benign thyroid lesions in children and adults.

Rearrangements of the RET proto-oncogene may occur in both naturally occurring and radiation-induced papillary thyroid carcinomas. Conflicting results on the frequency and type of RET/PTC rearrangements have been reported in relation to age, radiation exposure, and histological tumor variant. We designed the present study to evaluate in a single laboratory, using the same methodologies, the pattern of RET/PTC activation in thyroid tumors from different groups of patients (exposed or not exposed to radiation, children or adults, with benign or malignant tumors) in relationship to the above mentioned variables. We studied 154 patients with benign nodules (n = 65) or papillary thyroid cancer (n = 89). In the last group, 25 were Belarus children exposed to the post-Chernobyl radioactive fallout, 17 were Italian adults exposed to external radiotherapy for benign diseases, and 47 were Italian subjects (25 children and 22 adults) with no history of radiation exposure. Among patients with benign thyroid nodules, 21 were Belarus subjects (18 children and 3 adults) exposed to the post-Chernobyl radioactive fallout, 8 were Italian adults exposed to external radiation on the head and neck, and 36 were Italian adults with naturally occurring benign nodules. The overall frequency of RET/PTC rearrangements in papillary thyroid cancer was 55%. The highest frequency was found in post-Chernobyl children and was significantly higher (P = 0.02) than that found in Italian children not exposed to radiation, but not significantly higher than that found in adults exposed to external radiation. No difference of RET/PTC rearrangements was found between samples from irradiated (external x-ray) or not irradiated adult patients, as well as between children and adults with naturally occurring, not irradiated, thyroid cancer. When analyzing the type of RET/PTC rearrangement (RET/PTC1 or RET/PTC3), no major difference was apparent. In addition, eight cases with an unknown RET/PTC rearrangement and three cases with the concomitant expression of RET/PTC1 and RET/PTC3 were found. No significant correlation was observed between the frequency and/or the type of RET/PTC rearrangement and clinical-epidemiological features of the patients such as age at diagnosis, age at exposure, histological variant, gender and tumor-node-metastasis (TNM) categories. RET/PTC rearrangements were also found in 52.4% of post-Chernobyl benign nodules, in 37.5% of benign nodules exposed to external radiation and in 13.9% of naturally occurring nodules (P = 0.005, between benign post-Chernobyl nodules and naturally occurring nodules). The relative frequency of RET/PTC1 and RET/PTC3 in rearranged benign tumors showed no major difference. In conclusion, our results indicate that the presence of RET/PTC rearrangements in thyroid tumors is not restricted to the malignant phenotype, is not higher in radiation-induced tumors compared with those naturally occurring, is not different after exposure to radioiodine or external radiation, and is not dependent from young age. Other factors, probably influenced by ethnic or genetic background, may act independently from or in cooperation with radiation, to trigger the DNA damage leading to RET proto-oncogene activation.

Adolescent↗