In our work we were interested in the toxicity of fluorine on various parameters stress: chlorophyll, proteins, and antioxidant system lichen Xanthoria parietina (L.) Th. Fr., for this purpose, thalli treated by sodium fluoride (NaF) at concentrations 0, 0.5, 1.0, 5.0 10.0 mM, time scale 24, 48 96 h. The analysis results obtained revealed that all evaluated showed significant variations compare...