Radiobiological shot noise explains Three Mile Island biodosimetry indicating nearly 1,000 mSv exposures

Chromosome Aberrations in a Group of People Exposed to Radioactive Releases from the Three Mile Island Nuclear Accident and Inferences for Radiation Effects

Recently, it has been proposed that the doses received from 133Xe released during the accident in 1979 at the Three Mile Island (TMI) plant in Pennsylvania were much higher than has been conventionally assessed, due to a gross underestimation of the relative biological effectiveness of electrons from beta-particle-emitting radionuclides within the body. The central evidence cited in support of this proposal was the doses derived from cytogenetic analyses of blood sampled in the mid-1990s from people living near TMI at the time of the accident. However, the chromosome aberration data show a marked discrepancy in biodosimetric estimates evaluated from the frequencies of stable translocations and unstable dicentrics (corrected for temporal attenuation), strongly suggesting that exposures to clastogenic agents occurred long after the TMI accident. Few details have been reported on the people providing the blood samples and how they were selected for study. Crucially, this lack of information includes the distributions in the exposed and control groups of age at sampling, which is a critical factor in interpreting translocation data. Contrary to the recent claim, these cytogenetic data offer no support to the suggestion of a serious underestimation of internal doses from beta particles or from 133Xe discharged during the TMI accident.

Disproportionate Impacts of Radiation Exposure on Women, Children, and Pregnancy: Taking Back our Narrative

Narratives surrounding ionizing radiation have often minimized radioactivity's impact on the health of human and non-human animals and the natural environment. Many Cold War research policies, practices, and interpretations drove nuclear technology forward by institutionally obscuring empirical evidence of radiation's disproportionate and low-dose harm-a legacy we still confront. Women, children, and pregnancy development are particularly sensitive to exposure from radioactivity, suffering more damage per dose than adult males, even down to small doses, making low doses a cornerstone of concern. Evidence of compounding generational damage could indicate increased sensitivity through heritable impact. This essay examines the existing empirical evidence demonstrating these sensitivities, and how research institutions and regulatory authorities have devalued them, willingly sacrificing health in the service of maintaining and expanding nuclear technology (Nadesan 2019). Radiation's disproportionate impacts should now be the research and policy focus, as society is poised to make crucial and long-lasting decisions regarding climate change mitigation and future energy sources (Brown 2019b).

De novo congenital malformation frequencies in children from the Bryansk region following the Chernobyl disaster (2000-2017)

BACKGROUND

Ionizing radiation and chemical pollution can disrupt normal embryonic development and lead to congenital malformations and fetal death. We used official government statistical data for 2000-2017 to test the hypothesis that radioactive and chemical pollutants influenced the frequency of de novo congenital malformations in newborns of the Bryansk region of southwest Russia.

METHODS

A variety of statistical approaches were used to assess congenital malformation frequencies including the Shapiro-Wilk test, White's homoscedasticity test, Wilcoxon T-test, Spearman's rank correlation test, and the inversely proportional regression.

RESULTS

We found that the frequency of polydactyly, multiple congenital malformations, and the frequency of de novo congenital malformations in newborns were significantly higher (p = 0.001-0.054) in regions with elevated radioactive, chemical and combined contamination. Polydactyly, multiple congenital malformations, and the sum of all congenital malformations were 4.7-7.4 times, 2.5-6.8 times, and 3.5-4.6 times higher in contaminated regions in comparison with the control group. The combination of both radioactive and chemical pollutants led to significantly higher frequencies of multiple congenital malformations when compared to regions with only one pollutant (radiation alone: 2.2 times, p = 0.034; chemical pollutants alone: 1.9 times, p = 0.008) implying that the effects of these stressors were at minimum additive. Although there was a trend for decreasing frequencies of multiple congenital malformations during the 2000-2017 period in areas of combined pollution, the opposite was true for regions with radioactive or chemical pollutants alone. However, overall, our models suggest that the frequency of multiple congenital malformations in areas of combined pollution will significantly (p = 0.027) exceed the frequencies observed for regions containing radioactive or chemical pollutants alone by 39.6% and 45.7% respectively, by 2018-2023.

CONCLUSION

These findings suggest additive and potentially synergistic effects of radioactive and chemical pollutants on the frequencies of multiple congenital malformations in the Bryansk region of southwestern Russia.