Subchronic exposure of BALB/c and C57BL/6 strains of Mus musculus to the radioactive environment of the Chornobyl, Ukraine exclusion zone

• Published in: Environmental toxicology and chemistry 2001-12, Vol.20 (12), p.2830-2835
• Main Authors: Rodgers, Brenda E., Chesser, Ronald K., Wickliffe, Jeffrey K., Phillips, Carleton J., Baker, Robert J.
• Format: Article
• Language: English
• Subjects: Animal, plant and microbial ecology; Animals; Applied ecology; BALB/c; Biological and medical sciences; C57BL/6; Chernobyl; Chornobyl; DNA Damage; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on vertebrates; Environmental Exposure; Female; Fundamental and applied biological sciences. Psychology; Male; Mammalia; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Micronucleus test; Micronucleus Tests; Mus musculus; Power Plants; Radiation Injuries; Radioactive Hazard Release; Radioactive Pollutants - adverse effects; Radioisotopes - pharmacokinetics; Risk Assessment; Ukraine
• ISSN: 0730-7268; 1552-8618
• DOI: 10.1002/etc.5620201223

Environmental contamination resulting from the Chornobyl, Ukraine, disaster offers a unique opportunity to examine the in vivo biological effects of chronic, low‐dose exposure to radiation. Laboratory studies of acute exposure to ionizing radiation have been used to estimate risk and potential human health effects by the extrapolation of laboratory data to situations of low‐dose environmental radiation exposure. Few studies, however, have explored the biological consequences of low‐dose exposure via in situ environmental radiation in a sentinel species. In the present study, laboratory strains of Mus musculus (BALB/c and 57BL/ 6) were placed in environmental enclosures in the Red Forest region of the Chornobyl exclusion zone. Blood samples were obtained every 10 d, and the micronucleus (MN) test was employed to assess the potential for cytogenetic damage from exposure to Chornobyl radiation. Radionuclide uptake was monitored throughout the study, and dose was estimated for each individual as well as for their offspring. Total dose for the mice experimentally exposed to this environment averaged 1162 mGy for BALB/c (30 d) and 1629 mGy for C57BL/6 (40 d). A higher MN frequency for both strains was observed at day 10, although this change was only statistically significant in the C57BL/6 mice (χ23 = 13.41, p = 0.003). Subsequent samples from C57BL/6 resulted in values at or less than the initial frequencies. In BALB/c mice, an increase in MN was also evident at day 30 (χ22 = 10.38, p = 0.006). The experimental design employed here allows for the incorporation of traditional laboratory strains, as well as transgenic strains of Mus, as sentinels of environmental radiation contamination.