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Purpose: After the accidents of nuclear power plants at Chernobyl and at Fukushima, huge amounts of radioactive iodine were released into the atmosphere. Methods: We reviewed data on the health consequences of these accidents with a focus on thyroid consequences. Results: Among the 2 million children who were living in highly contaminated regions in Belarus, Ukraine and Russia, 7000 cases of thyroid cancer had occurred in 2005. This is the most significant radiation-induced consequence of the Chernobyl accident. The increased incidence of thyroid cancer observed in adult population who lived in these highly contaminated regions is at least in major part related to screening and it is not possible to individualize among these thyroid cancers those that are potentially caused by radiation exposure. For populations who lived outside these regions at the time of the accident, there is no detectable consequence of the radiation exposure on the thyroid gland. Among children who lived nearby the Fukushima power plant in 2011, there is currently no evidence of an increased incidence of thyroid cancer. Ultrasonography screening in these individuals detected a number of thyroid cancers that are probably not related to the accident. Because thyroid cancer is frequent, studies have been carried out to distinguish radiation-induced from their sporadic counterparts, and genomic signatures might be helpful. Conclusions: The consequences of the Chernobyl accident clearly demonstrate that populations living nearby a nuclear power plant should be protected in case of accident by sheltering, food restrictions and prophylaxis of thyroid irradiation by potassium iodine administration, if the predicted estimated dose to the thyroid gland of children might be >50 mGy. These countermeasures should be applied in priority to children, adolescents and pregnant women; they are safe and effective. [ABSTRACT FROM AUTHOR]

Whereas an RBE > 1 is described for very low-energy X-ray beams (in the range of 25–50 kV), there is a consensus that the RBE of X-rays (from 0.1 to 3 MeV) is equal to 1, whatever the energy or dose rate of the beam. Comparisons of X-ray beam dose rates are scarce even though these beams are widely used in medical diagnosis or radiotherapy. By using two dose rates (0.63 and 2.5 Gy.min−1) of high-energy X-rays on normal endothelial cells (HUVECs), we have studied the clonogenic assay, but also viability/mortality, cell cycle analysis and measured cellular senescence by flow cytometry, and have performed gene analysis on custom arrays. In order to consolidate these data, we performed localized irradiation of exteriorized small intestine at 0.63 and 2.5 Gy.min−1. Interestingly, in vivo validation has shown a significantly higher loss of weight at the higher dose when irradiating to 19 Gy a small fragment of exteriorized small intestine of C57Bl6J mice. Nevertheless, no significant differences were observed in lesioned scores between the two dose rates, while bordering epithelium staining indicated twofold greater severe damage at 2.5 Gy.min−1 compared to 0.63 Gy.min−1 at one week post-irradiation. Taken together, these experiments systematically show that the relative biological effectiveness of photons is different from 1 when varying the dose rate of high-energy X-rays. Moreover, these results strongly suggest that, in support of clonogenic assay, multiparametric analysis should be considered to provide an accurate evaluation of the outcome of irradiated cells. [ABSTRACT FROM AUTHOR]

Catastrophic acute bilateral lower limbs necrosis associated with COVID-19 as a likely consequence of both vasculitis and coagulopathy A few cases of digital ischaemia and necrosis have also been reported in association with coagulopathy.3,4 Bellosta et al.,5 who conducted an observational study of 20 patients infected by COVID-19 and treated for acute lower limb ischaemia, suggested a higher incidence of acute limb ischaemia in COVID-19 positive patients. Characterization of acute acro-ischemic lesions in non-hospitalized patients: a case series of 132 patients during the COVID-19 outbreak. [Extracted from the article]

It is important that in radioiodine dosimetry for low levels of daily intake, allowance must be made for the normal daily intake of stable iodine. This intake varies from one region to another, and variations are observed from one person to the next within a region, depending on eating habits. Measuring iodine in the urine over 24 hours can indirectly assess these variations. Analysis of the total iodine in the urine was carried out for 69 French people living in a temperate maritime region or in mainland France. This study justifies individual assessment of the coefficient of iodine transfer to the thyroid by means of this survey based on the urinary iodine analysis. The consequences for man of the release of 129I around a nuclear reprocessing plant were analyzed by applying the methodology published previously by the authors. A software program based on the iodine biokinetic model recommended by the ICRP was used to calculate the daily urine excretion of 129I for five different diets of total iodide in a ratio of 10-4 for 129I/127I. This model makes it possible to set a practical detection limit of 20 mBq (0.003 µg). This approach is important from a practical point of view for health physicists involved in routine monitoring of workers in the nuclear field and members of the public exposed to radioiodine released into the environment. [ABSTRACT FROM AUTHOR]