Effects of acute gamma irradiation on soil invertebrates in laboratory tests

¹ National Institute of Radiological Sciences, Chiba 263-8555, Japan
² Yokohama National University, Yokohama 240-8501, Japan

Abstract

An understanding of the dose-effect relationships of ionising radiation for nonhuman biota establishes important baselines for the radiological protection of ecosystems. We used standard laboratory tests to examine the dose-effect relationships of gamma radiation on the survival, growth and reproduction of the earthworm, Eisenia fetida (Oligochaeta). Adult E. fetida were acutely irradiated with increasing doses of gamma radiation, and the subsequent survival, growth in wet weight and number of offspring were examined. The 50% lethal dose (LD₅₀) was 825 Gy, and the 10% and 50% effective doses (ED₁₀ and ED₅₀) for growth were 20.2 and 94.7 Gy, respectively. The ED₁₀ and ED₅₀ for reproduction were 3.3 and 11.1 Gy, respectively.