In this paper, a method based on NMR measurements for studying the ability of ligands to interact with DNA is proposed. Via R1(SE) and R1(NS) spin-lattice relaxation rate analysis and temperature dependence, it is possible to investigate the DNA-ligand complexing. This approach appears very appropriate for testing the affinity of pollutants and others chemicals in the environment towards nucleic acid. As a standard method for large-scale screening of molecules resulting from human activity, it could be very useful for identifying potential mutagens and toxic compounds.