In which hemisphere is the radiation level higher and why?

At the moment, the problem of radiation is of very high importance for life on earth. According to scientific research, Larisa Fabarisova, in the annual journal of the Russian Academy of Sciences, indicates that the radioactive background is higher in the eastern hemisphere. This is due to several major man-made disasters that have occurred over the past 55 years, the Chernobyl disaster, the disaster at the Fukushima-1 station and several minor accidents that occurred during the transportation of shears and storage of nuclear waste. Nuclear pollution is almost entirely man-made, and causes severe harm to the environment.