At the base of the Chernobyl nuclear disaster there were procedural errors during a safety test on the RBMK No. 4 nuclear reactor of the plant, aimed at obtaining the final approval of the plant, which consisted in verifying the possibility of powering the pumps of the cooling system even in the event of an electrical blackout, using the electricity produced by the inertial movement of the turbines for the time necessary to activate the emergency diesel-electric generating sets.
Identical tests had already been conducted in the past: three had been held since 1982, with negative results. The test that caused the accident had been postponed by 10 hours compared to the scheduled time: this implied that the staff on duty who had to perform it were not the same team that had prepared for the purpose.
Impacts of radiation exposure in the Chernobyl Exclusion Zone
The study: Impacts of radiation exposure on the bacterial and fungal microbiome of small mammals in the Chernobyl Exclusion Zone, published on the The Journal of animal ecology, said: "Environmental impacts of the 1986 Chernobyl Nuclear Power Plant accident are much debated, but the effects of radiation on host microbiomes have received little attention to date.
We present the first analysis of small mammal gut microbiomes from the Chernobyl Exclusion Zone in relation to total absorbed dose rate, including both caecum and faeces samples. We provide novel evidence that host species determines fungal community composition, and that associations between microbiome (both bacterial and fungal) communities and radiation exposure vary between host species.
Using ambient versus total weighted absorbed dose rates in analyzes produced different results, with the latter more robust for interpreting microbiome changes at the individual level. We found considerable variation between results for fa ecal and gut samples of bank voles, suggesting faecal samples are not an accurate indicator of gut composition.
Associations between radiation exposure and microbiome composition of gut samples were not robust against geographical variation, although we identified families of bacteria (Lachnospiraceae and Muribaculaceae) and fungi (Steccherinaceae and Strophariaceae) in the guts of bank voles that may serve as biomarkers of radiation exposure.
Further studies considering a range of small mammal species are needed to establish the robustness of these potential biomarkers. "