Space rockets are regularly launched from the Baikonur Cosmodrome in Kazakhstan. The ecological impact of territories affected by the consequences of space rocket activities on the environment is a significant concern. On July 27, 2006, the Dnepr rocket was launched from the Baikonur Cosmodrome, resulting in an abnormal situation and its emergency fall. The rocket fuel components, heptyl, and amyl, led to decontamination and reclamation activities. However, the self-restoration of soil and vegetation cover is currently in the earliest stages. Consequently, an assessment of the remote consequences of the accidental fall of the Dnepr launch vehicle for environmental objects was conducted. The study involved eco-toxicological characterization of habitat conditions, assessment of species diversity, determination of key morphophenetic indicators, and the genetic status of indicator species as the main parameters. The results revealed an increased level of genotoxicity in soils at the accident site. While there were deviations from the norm in some morphophenetic and cytogenetic parameters in indicator animals, they were not critical for their existence in this territory. Possibly, at the physiological level, they exhibit a high enough adaptation potential and compensatory mechanism.

Due to the large number of nuclear power plants around the globe and the growing threat of radioactive accidents, a complex assessment of the biological consequences of the Chornobyl disaster is a relevant issue. Study of mutagenic activity of prolonged and chronic action of radionuclide pollution of soil in the Chornobyl Exclusion Zone long after the accident will allow us to identify the current level of threat they pose to the human genome and can reveal specific cytogenic markers of radionuclide environmental pollution. For this purpose, we germinated seeds of wheat of soft winter varieties Smuhlianka and Bohdana in soil samples from the Chornobyl Exclusion Zone 35 years after the disaster. Specific activity of Cs-137 and Sr-90 accounted for 4.5- 28.2 kBq/kg. To determine the frequency and range of chromosomal aberrations, we used the anaphase-telophase method. In aberrant cells, we studied extracellular distribution of chromosomal disorders. The frequency of aberrant cells was 3.53-7.55 times above the spontaneous level. High mutagenic activity remained in the conditions of the lowest density of radionuclide pollution of soil. The range of chromosomal disorders mostly included paired fragments and bridges and containd chromosomal acentric rings, binding of chromosomes, myocardium, and lagging and leading chromosomes. Radionuclide pollution in the Chornobyl Exclusion Zone induced multiple cellular aberrations in the rhizome meristem, the share of which was the highest in case of low specific radionuclide pollution of soil, and exhibited a tendency towards decrease against the background of the highest density of radionuclides. Pollution of the environment with radionuclides as a result of disasters at nuclear energy objects poses a threat to the human genome and is a global problem, requiring state support to solve through systematic genetic monitoring in readionuclide-polluted territories and areas adjacent to them.

BACKGROUND Informal electronic waste (e -waste) reprocessing in Nigeria is reportedly substantial in Africa, putting the growing exposed population at high risk of metal toxicity. This study aimed to investigate the existence of chromosomal aberration in the growing e -waste exposed populations in Nigeria, using induction of micronuclei (MN) expression in peripheral blood as an indicator. METHODS In this cross-sectional study, 632 consenting participants were recruited from South-West Nigeria, consisting of 381 e -waste workers (EWW), 120 environmental e -waste exposed participants (EEP) and 131 age -matched unexposed participants (UP) serving as controls. A validated structured questionnaire was used to assess exposure pattern while frequency of micronucleated polychromatic erythrocytes (MNPCE)/1000PCE in peripheral blood film was determined by modified micronucleus assay. RESULTS A duration of exposure of >= 5 years and exposure frequency >= 6 hours/day; 6 days/week (9360 hours in any 5year duration) was observed in both EWW and EEP. Routes of exposure observed in EWW entailed eyes, oral cavity, nasal cavity and skin. EWW that used personal protective equipment (PPE) while working was barely 10.24% while non -PPE users constituted the majority (89.76%) of the studied population. Frequency of MNPCE)/1000PCE in EWW (22.70 +/- 0.15) was significantly higher than in EEP (4.17 +/- 0.28), which in turn was significantly higher than the lowest frequency (0.99 +/- 0.76) observed in UP (p<0.001). CONCLUSION The observed exposure pattern and the comparatively higher MN induction in the e -waste populations may suggest risk of significant cytogenetic damage and aberrant chromosomal changes associated with occupational e -waste reprocessing in Nigeria.