Human activities have led to environmental pollution also industrial growth and the gradual transition to urbanization are the main causes of the growth of different types of environmental pollutants. The continuation of studies on air quality biomonitoring in the context of “green revolution” have renew the way to use "green tools" using higher plants with specific capabilities-as biomonitors. In the experiments carried out in several locations, with different degrees of pollution, the aim was to assess the responses of plants, aspect and biochemical composition of the biomonitors exposed to various pollutants compared to the unexposed ones, the activity, the methodology and the results obtained being the subject of this paper. These secondary air pollutants are dangerous for living organisms because of their high oxidative potential. In this paper, studies were performed based on the analysis of antioxidant compounds that represent a structural class of chemicals (enzymes) with a wide range of biological functions, with the role of inhibiting free radicals. The experience gained in the study of plant biomonitoring is the basis for the development of new methods of use and study with applicability in research projects due to the immediate, multiple and distinct benefits and as well as the development of efficient and accessible methods.