The research is related to the use of the cytogenetic observations for the analysis of the effects caused to marine organisms by the synergistic action of radioactive and conventional pollutants. The methodological approach is applied on field data in order to highlight the actual synergistic effects. The bioindicators of the marine environment to be studied, bivalves – mussels, is a common and representative species of the Mediterranean marine ecosystem, and are collected from several coastal areas in Greece that host shellfish cultivation activities. The methodological approach includes the cytogenetic observations and the recording of abnormalities caused by the exposure of organisms to the radioactive substances and to the conventional pollution (i.e., chemical pollution or environmental stressors like temperature and salinity). The statistical analysis of the collected data provides the appropriate information for the identification of the different sources of pollution. It also allows for the design of an integrated methodology for the future prediction of the synergistic action of the pollutants. Furthermore, by the use of the data retrieved by the international literature and by our previous research works it will be possible to extrapolate our findings from one taxonomic level to the other (from cytogenetic, up to ecosystem level) and from one ecosystem to the other. The project is conducted at the ENvironmental Radioactivity, Aerosol, air quality & Climate change Technologies Laboratory of National Centre for Scientific Research ‘Demokritos’, under the scientific mentoring of Dr Heleny Florou (Collaborating Director of Research). This research is co-financed by Greece and the European Union (European Social Fund- ESF) through the Operational Programme «Human Resources Development, Education and Lifelong Learning» in the context of the project “Reinforcement of Postdoctoral Researchers – 2nd Cycle” (MIS-5033021), implemented by the State Scholarships Foundation (ΙΚΥ) (no of contract: 2019-050-0503-17350).