Due to the increasing pollution of the natural environment, the amount of impurities that can accumulate in herbs and plants used for therapeutic purposes as medicinal plants also increases. As many plant materials have medicinal properties and have been used as medicinal remedies,they must be subjected to rigorous assessments according to material quality standards.Presently, however, there is no guarantee that there has been no change in the amount and content of medicinal bioactive substances, compared to plants used years ago in traditional folk medicine. At present, there are great prospects in the use of medical plants, especially if the medicinal plants are free from pollution originating from the contaminated natural environment. The attention of researchers should focus not only on seeking new bioactive compounds and finding new drugs in plants, but also on ensuring high standards of quality regarding the evaluation of the chemical purity of plants growing in the environment exposed to contamination and pollution. The combination of both challenges can help patients suffering from increasing numbers of ailments and diseases of civilization. Researchers must also be actively involved in the process of detection any harmful substances penetrating from the environment into plants by applying various biomedical and chemical techniques to detect some novel, as yet unknown threats, in order not to expose patients to them.