Linear threshold effects of Daphnia magna γ-irradiation at low doses

Issues

Authors

Sarapultseva E.I., Malina Ju.Yu., Sarapultsev B.I.¹
Obninsk State Technical University for Nuclear Power Engineering (IATE), Obninsk.
¹South Ural State University, Chelyabinsk

Abstract

With γ-irradiation of Daphnia magna Straus, dose-independent effects were observed in the range 0.01-0.1 Gy with a threshold transition to a new lethality level at 1.0 Gy. This 25% lethality level was retained for doses up to 100 Gy and was followed by the second transition to the 100% lethality level at doses 250-600 Gy. Similar dose-independent threshold effects were found for Daphnia magna fertility, number of litters and cardiac rate. The mechanism of nonlinear effects of irradiation at low doses has been connecting with the epigenetic processes in the cells and the elimination of genetic damages. The obtained results provide a crucial argument in support of environmental safety of nuclear facilities at normal operation and of medical radiology techniques.

Key words
Acute gamma irradiation, Daphnia magna Straus crustaceans, dose-independent effects, salting transition, lethality level, threshold effects, fertility analysis.

References

1. Bychkovskaya I.B. The problem of distant radiation death of cells. Moscow: Energoatomizdat, 1986. 160 p.

2. Bychkovskaya I.B., Fedortseva R.F., Antonov P.V. and others. Special cellular effects and physical effects of irradiation in small doses. S.Pb., SPICE Publ., 2006. 150 pp.

3. Egorova E.I. Changes in motor activity of infusorians after gamma irradiation in a wide range of doses as informative methods for biotesting. Radiation Biol. Radioecology. 2007 (in press).

4. Ivanov V.K., Tsyb A.F. Medical radiological consequences of Chernobyl for the population of Russia: assessment of radiation risks. Moscow, Medicine Publ., 2000. 392 p.

5. Sarapultsev B.I., Geraskin S.A. Genetic basis of radioresistance and evolution. Moscow, Energoatomizdat Publ., 1993. 208 p.

Full-text article (in Russian)