The occurrence of chemical contaminants with DNA-damaging capacity in the environment represents a threat to human health as well as to the health of the ecosystem. This mini-review describes studies that were aimed to monitor at field conditions, the presence of such environmental toxicants and their DNA-damaging effects in aquatic and terrestrial species, as well as in birds. It is obvious that these studies, in particular are abundantly performed in fish and aquatic invertebrates, have brought forward new information on the levels and genotoxic effects of these compounds which complements data coming from monitoring the abiotic fractions of the ecosystem, thereby demonstrating that the ecogenotoxicological approach is fruitful. However, in order to assess the genotoxic impact on the health of the ecosystem, a second generation type of field studies is required focusing on adverse effects on biodiversity and on survival potency. For this, the application of DNA microarray-based technologies provides new opportunities.