1.
Rääf, Christopher, et al.
(författare)
Introduction of a method to calculate cumulative age- And gender-specific lifetime attributable risk (LAR) of cancer in populations after a large-scale nuclear power plant accident
2020
Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 15:2
Tidskriftsartikel (refereegranskat) abstract
The effect of age and gender in risk estimates related to long-term residence in areas contaminated by nuclear power plant fallout was evaluated by applying the lifetime attributable risk (LAR) concept to an existing exposure model that was previously used for cumulative effective dose estimates. In this study, we investigated the influence of age distribution on the number of cancer cases by applying five different age distributions from nuclear power-producing countries (India, Japan, South Korea, and the United States), and Egypt because of intentions to develop nuclear power. The model was also used to estimate the effective dose and gender-specific LAR as a function of time after fallout for the offspring of the population living in 137Cs fallout areas. The principal findings of this study are that the LAR of cancer incidence (excluding non-fatal skin cancers) over 70 y is about 4.5 times higher for newborn females (5.4% per MBq m-2 of initial 137Cs ground deposition) than the corresponding values for 30 y old women (1.2% per MBq m-2 137Cs deposition). The cumulative LAR for newborn males is more than 3 times higher (3.2% versus 1.0% per MBq m-2 137Cs deposition). The model predicts a generally higher LAR for women until 50 y of age, after which the gender difference converges. Furthermore, the detriment for newborns in the fallout areas initially decreases rapidly (about threefold during the first decade) and then decreases gradually with an approximate half-time of 10-12 y after the first decade. The age distribution of the exposed cohort has a decisive impact on the average risk estimates, and in our model, these are up to about 65% higher in countries with high birth rates compared to low birth rates. This trend implies larger average lifetime attributable risks in countries with a highly proportional younger population. In conclusion, the large dispersion (up to a factor of 4 between newborns and 30 y olds) in the lifetime detriment per unit ground deposition of 137Cs over gender and age in connection with accidental nuclear releases justifies the effort in developing risk models that account for the higher radiation sensitivity in younger populations.
2.
Rääf, Christopher L., et al.
(författare)
Average uranium bedrock concentration in Swedish municipalities predicts male lung cancer incidence rate when adjusted for smoking prevalence: Indication of a cumulative radon induced detriment?
2023
Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 855
Tidskriftsartikel (refereegranskat) abstract
Bedrock U has been used as a proxy for local indoor radon exposure. A preliminary assessment of cancer incidence rate in a cohort of 809,939 adult males living in 9 different Swedish counties in 1986 has been used to correlate the cumulative lung cancer and total cancer (excluding lung) incidence rates between 1986 and 2020, respectively with the municipality average value of bedrock U concentration obtained from Swedish geological Survey (SGU). To control for regional difference in tobacco smoking, data on county average smoking prevalence, obtained from a survey conducted by the Public Health Agency of Sweden from 2001 to 2004, was used. Regression analysis shows that there is a significant positive correlation between smoking prevalence adjusted lung cancer incidence rate in males and the municipality bedrock U concentration (R2 = 0.273 with a slope 5.0 ± 0.87·10−3 ppm−1). The correlation is even more significant (R2 = 0.759 with a slope = 4.8 ± 0.25·10−3 ppm−1) when assessed on population weighted cancer incidence data binned in nine intervals of municipality average bedrock U concentration (ranging from 0.97 to 4.9 ppm). When assessing the corresponding correlations for total cancer incidence rate (excluding cancer of the lung) with adjustment for smoking prevalence, there appears to be no or little correlation with bedrock U concentration (R2 = 0.031). We conclude that an expanded future study needs age-standardized cancer incidence data to obtain a more consistent exposure-response model. Such model could be used to predict future lung cancer cases based on geological survey maps of bedrock U as an alternative to laborious indoor radon measurements, and to discern what future lung cancer rates can be expected for a population nearing zero smoking prevalence, with and without radon prevention. © 2022 The Authors
3.
Tondel, Martin, et al.
(författare)
Dose–response analysis of protracted absorbed organ dose and site-specific cancer incidence in Sweden after the Chernobyl nuclear power plant accident
2023
Ingår i: Environmental Epidemiology. - : Lippincott Williams & Wilkins. - 2474-7882. ; 7:6
Tidskriftsartikel (refereegranskat) abstract
Background: Adult males in Sweden exhibit an increased risk of cancer associated with an increased absorbed dose to the colon from the Chernobyl accident. Methods: A closed cohort, with information on hunter status, included all individuals living in northern Sweden in 1986. Complete annual information on exposure to 137Cs at the dwelling coordinate was available for a total of 2,104,101 individuals. A nested case-control method with four controls matched for year of cancer diagnosis and year of birth, was used. Individual absorbed organ doses were calculated between 1986 and 2020 including external and internal exposure. Hazard ratios (HR) per mGy with 95% confidence intervals (95% CI) were calculated using conditional logistic regression adjusted for rural/nonrural habitat, education level and pre-Chernobyl cancer incidence 1980 to 1985. A total of 161,325 cancer cases in males and 144,439 in females were included. Results: The adjusted HR per mGy for all cancer sites combined was 1.027 (95% CI = 1.022, 1.031) in males and 1.011 (95% CI = 1.006, 1.017) in females. In a post hoc analysis accounting for both remaining confounding from hunter lifestyle and the pre-Chernobyl cancer incidence by county, the adjusted HR per mGy for all cancer sites combined was 1.014 (95% CI = 1.009, 1.019) in males and 1.000 (95% CI = 0.994, 1.006) in females. The post hoc analysis suggested an increased risk of cancer in the colon, pancreas, and stomach, respectively, in males, and lymphoma in females. Conclusions: Increased cancer risk estimates were found for some specific cancer sites but remaining uncontrolled confounding due to hunter lifestyle could not be ruled out.
4.
5.
Thomas, Rimon, et al.
(författare)
Natural radioactivity and element characterization in pit lakes in Northern Sweden
2022
Ingår i: Plos One. - : Public Library of Science (PLoS). - 1025-9112 .- 1616-1068 .- 1932-6203. ; 17:3
Tidskriftsartikel (refereegranskat) abstract
Northern Sweden has been the object of intense metal mining in the last decades producing several water-filled open-pits, or pit lakes. Most of these pit lakes have been limed to maintain a good water quality and to prevent generation of acidic water that could leach the exposed rocks and release metals into water. The aim of this work was to examine the concentration of stable elements and naturally occurring radionuclides in water and sediment samples from pit lakes originating from non-uranium mining activities in Northern Sweden. Surface water and surface sediments were collected from 27 pit lakes in Northern Sweden. Water quality parameters, concentration of stable elements and radionuclides were measured by a water probe, ICP-MS and XRF, and alpha and gamma spectrometry, respectively. Furthermore, a multivariate statistical analysis (PCA) was performed on the water samples and sediments. In general, the quality of the surface water was good, but some lakes had low pH values (2.5–5.7), and high concentrations of Fe (up to 200 mg/L) and other metals (e.g. Zn, Cu). When relating the metal concentrations in sediments in pit lakes with the concentration found in natural lakes, some sites had relatively high levels of Cu, As, Cr and Pb. The activity concentration of 210Po, and U and Th isotopes in water and sediment samples were at environmental levels, as was the ambient dose equivalent rate at these sites (range 0.08–0.14 μSv/h).
6.
Piñero-García, Francisco, et al.
(författare)
Radiological impact of naturally occurring radionuclides in bottled water
2021
Ingår i: Food Control. - : Elsevier BV. - 0956-7135. ; 130
Tidskriftsartikel (refereegranskat) abstract
Consumption of bottled water is increasing year after year in Europe. Due to the local geology from where the water is extracted; bottled water could be enhanced with radionuclides. This study focuses on the activity concentrations of 210Po, 210Pb, 226Ra, 228Ra, 234U and 238U in bottled water available in the Swedish market, to assess the radiological impact to different age groups. The results showed that among the 26 brands studied, only three could exceed the threshold value for drinking water: 0.1 mSv/year. For two brands, the dose was mainly due to the activity concentrations of 238U and 234U being up to 714 and 1162 mBq/L, respectively. While for one brand, the dose was mainly due to the activity concentration of both 210Po and 210Pb being around 100 mBq/L. For the remainder brands, 228Ra was the main contributor to the committed effective dose.
7.
Thomas, Rimon, et al.
(författare)
Natural radioactivity in a former mining lake in Central Sweden
2016
Ingår i: SweRays Workshop, Stockholm, Sweden, Aug 25-26.
Konferensbidrag (övrigt vetenskapligt/konstnärligt) abstract
Historically Sweden (the major metal mining country in the European Union), with more than 2700 mines, gathers around 30000 sites that have been minor mines and/or quarries (according to the database of Geological Survey of Sweden, SGU). This huge activity has implied enormous quantities of generated mining wastes, considered, in some cases NORM (Naturally Ocurring Radioactive Material). In this work, one former mine lake nearby Kolsva (in Västmanland) was radiometrically characterized. Water samples from the pit lake, sediment and soil/rock samples were measured via alpha (for 238U, 234U, 232Th and 230Th isotopes) and via gamma spectrometry (for radionuclides belonging to both 238U and 232Th natural series). Also measurement of elementary composition in water (via ICP-MS) and in sediments (via XRF) was carried out. Regarding 238U isotopes, for instance, 100 to 600 mBq/kg were found in water samples. Having into account that an average value of this isotope in non-affecting environmental waters is around 20-30 mBq/kg it is quite clear that this site has enhanced U levels in superficial waters. These moderated levels in natural radionuclides were also confirmed in some rocks from this site with values above 1Bq/g in natural radionuclides from 238U series. The found activity concentration values will contribute to increase the external doses received by people visiting these sites for recreation (swimming, fishing, diving) purposes. Keywords: Natural radionuclides, environmental samples, mining lakes
8.
Rääf, C., et al.
(författare)
Averting cumulative lifetime attributable risk (LAR) of cancer by decontamination of residential areas affected by a large-scale nuclear power plant fallout: Time aspects of radiological benefits for newborns and adults
2020
Ingår i: Journal of Radiological Protection. - : IOP Publishing. - 0952-4746 .- 1361-6498. ; 40:3, s. 790-814
Tidskriftsartikel (refereegranskat) abstract
The averted cumulative lifetime attributable risk (LAR), the residual dose and highest ground deposition of 137Cs complying with a reference dose level of 20 mSv y-1 to an individual returning after one year to an area contaminated by nuclear power plant (NPP) fallout were evaluated by applying an existing exposure model designed to compute age- and gender-dependent time integrated LAR. The model was applied to four types of nuclear fallout scenarios, partly based on data from the Chernobyl and Fukushima releases and from theoretical source terms from Swedish NPPs. For rapid decontamination measures that achieve a 50% relative reduction in external dose rate within 1 y, compliance with the reference level 20 mSv y-1 can be attained for an initial 137Cs ground deposition of up to 2 MBq m-2 with relaxed food restrictions. This compliance can be attained at even higher ground deposition (up to 3.5 MBq m-2) if using the strict food restrictions employed in Japan after 2011. Considering longer than 1 year return times it was also found that the benefit of implementing decontamination decreases rapidly with time (2-3 y half-time), especially if the fallout has a high initial 134Cs to 137Cs activity ratio and if the ecological half-time of the external dose rate is short (<5 y). Depending on fallout scenario the averted cumulative LAR for newborn girls by decontamination that is achieved after 5 y is only between 6% and 11% of that obtained by evacuation alone during the same time, indicating a rather limited radiological benefit of decontamination if delayed more than a few years. We conclude that decision makers and emergency response planners need to consider that protracted decontamination measures may have limited radiological benefit compared with evacuation in terms of averted future cancer cases, albeit it may have other societal benefits.
9.
10.
Isaksson, Mats, 1961, et al.
(författare)
Calculations of the deposition of 137Cs from nuclear bomb tests and from the Chernobyl accident over the province of Skane in the southern part of Sweden based on precipitation
2000
Ingår i: Journal of Environmental Radioactivity. - 0265-931X .- 1879-1700. ; 49, s. 97-112
Tidskriftsartikel (refereegranskat) abstract
The deposition of 137Cs over the province of Skane (an area of about 100x100km2) in the southern part of Sweden has been investigated. The origin of the deposition of 137Cs is, in about equal parts, from nuclear weapons tests and from the Chernobyl nuclear accident and amounts to about 1-3kBq/m2. The activity concentrations of 134Cs and 137Cs in soil samples from 16 sites distributed in a grid pattern over the investigated area have been measured and the depositions from the nuclear weapons tests and from the Chernobyl accident have been separated. These pre- and post-Chernobyl activities have been compared with depositions calculated from measurements of the activity concentrations of 134Cs and 137Cs in precipitation at two places and from measurements of the precipitation from a network of between 113 and 143 precipitation stations. Comparisons with in situ measurements and with aerial survey measurements have also been made. The agreement is good gain and it has been possible to gain a good and detailed knowledge in retrospect of the deposition from measurements of the deposition per mm of precipitation from just a few stations, and of the precipitation from a network of stations. Copyright (C) 2000 Elsevier Science Ltd.
