Bryansk Oblast
Because of the Chernobyl disaster on April 26, 1986, part of the area of Bryansk Oblast has been contaminated with radionuclides (mainly Gordeyevsky, Klimovsky, Klintsovsky, Krasnogorsky, Surazhsky, and Novozybkovsky Districts). In 1999, around 226,000 people lived in areas with the contamination level above 5 Curie/km2. This was about 16% of the oblast's population.