Abstract. Our study introduces several ecotoxicological notions and aims to popularize bio testing on plants and fill some substantial gaps in its understanding. The results found on this research in this research can be very useful for choosing metallic-toxicity-resisting cultivars, which could decrease the risk of transfer into the food chain and also benefit the rehabilitation of contaminated soils. For this purpose, we used a combination of various tests – cytotoxic and genotoxic tests – the objective of which was to evaluate the matrices biologically contaminated by agents likely to introduce modifications often considered potentially harmful to the ecosystem. The evaluation was made by visualizing these agents’ effects on the plant. Therefore, we chose to test the effect of the two trace elements most widespread in the environment (lead and cadmium) and wastewater’s impact on three different species ( Allium cepa , Allium sativum , and Vicia faba ). The results revealed the inhibitive effect of toxins tested on the germinal faculty and on the extension of the roots of each species, with Allium cepa being very sensitive, contrary to Vicia faba , which seems to be more resistant, especially to lead. Whereas the micronucleus test highlighted the genotoxic impact of wastewater. By inducting anomalies within the genetic material of the plants named above, lead and cadmium affects the chromosomes number or the chromosome structure or both of them. Hence, the aneugenic and the clastogenic effects, the nuclear fragmentations, the micronuclei formation as well as mitotic indexes modification.