The effect of chronic exposure on the parameters of cytogenetic markers of senescence in the residents of the Techa riverside settlements

The understanding of the exposure effects on the human health could be improved by analyzing the influence of the chronic low dose rate exposure on the senescence of the immune system cells. It will also help to develop the measures aimed at the mitigation of the adverse effects. The objective of the study is to investigate the influence of the chronic low dose rate exposure on the senescence of the immune system cells using the cytogenetic markers. In the course of the research the authors evaluated the cellular senescence markers — genome instability and telomere depletion — in T-lymphocytes of the individuals exposed in the Southern Urals (exposure doses were 0.001 Gy — 4.7 Gy, the age of examined people was 40–89 years). The data analysis has demonstrated that the effect of chronic exposure on the T-cell senescence was indirect. Unstable chromosome aberrations occurred statistically significantly more frequently in exposed people aged 40–59 years (p = 0.012). Frequency of lymphocytes with micronuclei in exposed individuals differed in men and women (p = 0.001). Statistically significant decrease in the telomere length was revealed (for the chromosome arms 1q, 3p, 3q, 20p, 20q, 13q, 15p, 22q (p < 0.05); 19p, 21q (p < 0.01)).