Assessment of the Potential Toxic Effect of Organoclays as Sorbents on Various Biological Test Objects

Natural and modified clay minerals are widely used in environmental technologies to remove a wide range of toxic substances from aquatic and soil ecosystems. This study assessed the toxicity of synthesized organoclays compared to pure bentonite using microbiological, phytotoxic, and instrumental (biosensor) methods. Organoclay containing lauramine oxide (a non-ionic surfactant) was found to have an increased toxic effect on all test organisms analyzed. Based on the phytotesting parameters, radish was found to be the most sensitive test organism in these experiments, as it was significantly affected by toxic substances, demonstrating noticeable changes in its morphology and morphometry. Minimal toxicity was demonstrated for organoclay containing alkyl polyglucoside (a non-ionic surfactant), which was used in all tests. Furthermore, organoclay containing disodium cocoamphodiacetate (an amphoteric surfactant) also exhibited minimal toxicity in phytotesting, including germination assessment (radish) and evaluation of morphometric characteristics using a biosensor method. The study confirms that the type of organic modifier significantly impacts the biocompatibility of organoclays. Using fewer toxic surfactants can improve the environmental acceptability of these materials for use in cleaning up contaminated ecosystems.