Chromosomal Aberrations, Reproductive Success, Life Span, and Mortality in Irradiated Neanthes Arenaceodentata (Polychaeta)

摘要

The polychaete worm Neanthes arenaceodentata was used in experiments to determine possible relationships between short-term genotoxicity tests and reproductive and lethal consequences of exposure to ionizing radiation. Groups of juvenile N. arenaceodentata received one of four different radiation doses (2, 4, 8, and 16 Gy) to determine dose-effect estimates for chromosomal aberration induction, and groups of both adult and juveniles received one of seven different radiation doses (1, 4, 8.4, 46, 102, 500, and 1000 Gy) to determine dose-effect estimates for reproduction, mortality, and life span. Effects on reproduction and genetic material were observed at the lowest doses and in the same range; detrimental reproductive effects were observed at 1 to 4 Gy, and the frequency of chromosomal aberrations were significantly increased at 2 Gy. Only high doses resulted in acute mortality (>500 Gy) and decreased life span (>100 Gy). Dose-effect estimates for chromosomal aberration induction were dependant on radiation dose and on the stage of the cell cycle at the time of irradiation. Dose-effect estimates for reproduction were dependant on dose and the potential for repopulation of gonadal tissue. Such knowledge is required because factors, such as cell-cycle effects, may modify dose-effect estimates. It is concluded that short-term genotoxicity tests can be predictive of detrimental reproductive effects in those model systems for which basic cell kinetics and reproductive parameters are well known. 4 refs., 11 figs., 13 tabs. (ERA citation 13:019600)