The article presents a method to investigate the soil using an addition of spin labels, i.e. molecules with nitroxyl radicals, into the soil, and then, measurement of their mutual electro- paramagnetic resonance (EPR) signal. The peculiarity of spin-label molecules used in the method is defined by a critical functional group (e.g. aromatic amine) that wildly interacts with soil fragments, sends labeled molecules to a specified spatial localization in a complex soil system, and can play a role to bind them covalently to soil compounds. The aim of the method is to investigate the molecular mechanisms of interaction and binding of xenobiotics of organic origin to soil.The method includes the ascertainment of a critical functionality of xenobiotics, then synthesis of labeled molecule with a functionality as well as addition of the synthesized molecules to soil probe, and finally, registration of their mutual EPR spectra.