Aquatic Biota within the Chernobyl Accident Exclusion Zone: Consequences of the Long-Term Radiation Exposure

摘要

The effects of chronic radiation exposure on aquatic biota within the Chernobyl accident exclusion zone during 1998-2009 were studied. The absorbed dose rate for hydrohionts registered in range from 1.3 mGy/year to 3.4 Gy/year. The heightened chromosomal aberration rate in the embryo tissue of snails (up to 27%) and in the root meristems of higher aquatic plants (up to 18%) was determined. In hemolymph of snails from contaminated lakes the quantity of death cells averages 36-44%; the part of phagocytic cells averages 41-45%, as well as decrease of the young amoebocytes quantity to 10-20%. In peripheral blood of fish the high rate of abnormal red cells (up to 29%o) as different type of invaginations, ramifications, micronuclei etc. was marked. The high level of parasitic fungi and gall-producing arthropods of the common reed in the most contaminated lakes within the exclusion zone was registered. Above mentioned phenomenon may testify upon the decreasing of the parasitical stability of plant under impact of long-term radiation exposure.