Using Various Biomarkers for the Estimation of the Situation after an Accident at Siberian Chemical Plant

On April 6, 1993 near the town of Tomsk (Russia) there was an accident at the Siberian chemical plant (SCP) as a result of which an area of 200 square kilometres was polluted with radionuclides. Especially dangerous was the fallout of the plutonium-239; there were also traces of caesium-137 and cobalt-60. Scientists from Russia, Ukraine and The Netherlands have participated in the investigations of radiation doses. A cytogenetic method and investigation of tooth enamel by the method of electronic spin resonance (ESR), as well as micronuclei test were used to estimate the radioactive doses received by the population. The ESR signal intensity and cytogenetic aberration frequency in lymphocytes of the tooth donors showed a good correlation. The data obtained testify that 15% of the inhabitants of the Samus settlement received a dose of radiation effect exceeding 100 centrigray (cGy). In 87% of these cases there was reasonable agreement between laboratories. The distinctions concerned the results of the examinations of the fishermen where the method of ESR gave high results (80-210 cGy) and chromosomic method and micronuclei gave low ones (8-52 cGy). A large number of cytogenetically aberrated cells were especially observed in the people born between 1961 and 1969. It was found that during these years, serious failures at the Siberian chemical combine occurred causing radiation pollution of the district. The number of cells with cytogenetic aberrations was considerably less in the people arriving in Samus after 1980. Our experience shows the importance of collecting detailed information on the donors from whom samples were taken for radiation dose reconstruction.