Selected issues in the assessment of phytotoxicity of energy industry ash – an outline of the topic in a didactic context

Abstract

Ash from the energy industry belongs to the group of combustion by-products whose physicochemical properties determine both their potential environmental hazards and the possibilities for their secondary use. The aim of this article is to provide a synthetic analysis of selected research results concerning the phytotoxicity of energy ash and to assess the usefulness of plant-based tests in evaluating environmental risks associated with introducing ash into the environment. A review of the literature indicates that the impact of ash on plants is varied and depends on the origin of the ash, their chemical composition, dosage, the properties of the soil into which the ash is introduced, and, most importantly, the species of the test plant. Low doses of ash may stimulate plant growth, whereas higher doses lead to toxic effects related to high pH, chloride and sulfate content, as well as accumulation of heavy metals. The use of standardized phytotoxicity tests enables rapid and reproducible assessment of the influence of ash on plant life processes, and thus indirectly on the soil environment, supporting their potential safe use in accordance with the principles of sustainable development.