[Photodimerization of uracil in films and their use for dosimetry of genetically active ultraviolet irradiation].

On the basis of the known photodimerization of uracil it is proposed to use its films obtained by sublimation in vacuum for the dosimetry of genetically active UV radiation. Experimental estimations are presented of radiation dose rate resulting in a change of uracil optical density delta D/D0 under irradiation due to photodimerization for erythemal lamp lo-30. The data obtained are used for dosimetry of lethal damage of Chlamydomonas reinhardii. Estimations are also presented of the sun radiation dose rate which induce uracil photodimerization on the earth surface and in the extraterrestrial atmosphere.