Waste brick dust as a prospective eco-friendly alternative component of artificial soils for ecotoxicological studies

Current artificial soils for ecotoxicological studies contain non-renewable materials that must be mined, and their production and processing consume a lot of energy and generate a significant amount of carbon dioxide (CO₂). In this paper, waste brick dust is proposed as an alternative to calcium carbonate (CaCO₃), which is used for pH adjustment of the Organization for Economic Co-operation and Development (OECD) soils. The artificial soils containing brick dust are contaminated with boric acid as a reference substance in the concentration range of 100-500 mg/kg and studied in the tests with enchytraeids (E. crypticus), springtails (F. candida), and plants (L. sativa and B. napus). Experimental results shows the suitability of replacing calcium carbonate with waste brick dust, as neither toxicity nor ability of model organisms to inhabit the analyzed soil is found. A comparison with the standard OECD soil does not reveal any substantial differences between the parameters (survival, reproduction, and root elongation) of the applied ecotoxicological tests. The brick dust as waste material is found to have a lower carbon footprint than CaCO₃, while a similar amount of water is necessary for the adjustment of tests with both kinds of artificial soil. The waste brick dust can be considered as a suitable eco-friendly alternative to CaCO₃ in artificial soils for ecotoxicological studies.