The rate of X-ray-induced DNA double-strand break repair in the embryonic mouse brain is unaff ected by exposure to 50 Hz magnetic fi elds

Following in utero exposure to low dose radiation (10 – 200 mGy), we recently observed a linear induction of DNA double-strand breaks (DSB) and activation of apoptosis in the embryonic neuronal stem/progenitor cell compartment. No signifi cant induction of DSB or apoptosis was observed following exposure to magnetic fi elds (MF). In the present study, we exploited this in vivo system to examine whether exposure to MF before and after exposure to 100 mGy X-rays impacts upon DSB repair rates. Materials and methods : 53BP1 foci were quantifi ed following combined exposure to radiation and MF in the embryonic neuronal stem/progenitor cell compartment. Embryos were exposed in utero to 50 Hz MF at 300 m T for 3 h before and up to 9 h after exposure to 100 mGy X-rays. Controls included embryos exposed to MF or X-rays alone plus sham exposures. Results : Exposure to MF before and after 100 mGy X-rays did not impact upon the rate of DSB repair in the embryonic neuronal stem cell compartment compared to repair rates following radiation exposure alone. Conclusions : We conclude that in this sensitive system MF do not exert any signifi cant level of DNA damage and do not impede the repair of X-ray induced damage

Radiosensibilité comparative des cellules épithéliales de trachée de rats après irradiation alpha

La contamination interne par inhalation de radionucléides émetteurs alpha de haut TEL est le risque majeur de l'industrie nucléaire. Les cibles principales de la cancérogenèse pulmonaire sont les cellules épithéliales de l'appareil respiratoire. Une étude in vitro a été menée pour déterminer s'il existe une différence de radiosensibilité aux rayonnement alpha, des cellules épithéliales trachéales de deux souches de rats : Sprague Dawley et Wistar Furth-Fischer F344. Les cellules sont irradiées sédimentées au fond d'un puit spécifique à l'aide de sources électrodéposées de 241Am. L'évaluation de la survie cellulaire en fonction de la dose d'irradiation est complétée par un suivi cinétique de la formation et de la prolifération des colonies

Rapport du comité d'experts sur les radiations non ionisantes. 2017-2018

info:eu-repo/semantics/publishe

In vitro and in vivo genotoxicity of radiofrequency fields

International audienceThere has been growing concern about the possibility of adverse health effects resulting from exposure to radiofrequency radiations (RFR), such as those emitted by wireless communication devices. Since the introduction of mobile phones many studies have been conducted regarding alleged health effects but there is still some uncertainty and no definitive conclusions have been reached so far. Although thermal effects are well understood they are not of great concern as they are unlikely to result from the typical low-level RFR exposures. Concern rests essentially with the possibility that RFR-exposure may induce non-thermal and/or long-term health effects such as an increased cancer risk. Consequently, possible genetic effects have often been studied but with mixed results. In this paper we review the data on alleged RFR-induced genetic effects from in vitro and in vivo investigations as well as from human cytogenetic biomonitoring surveys. Attention is also paid to combined exposures of RFR with chemical or physical agents. Again, however, no entirely consistent picture emerges. Many of the positive studies may well be due to thermal exposures, but a few studies suggest that biological effects can be seen at low levels of exposure. Overall, however, the evidence for low-level genotoxic effects is very weak