Effects of Toxic Organic Compounds on Tenebrio molitor and Its Parasite Gregarina steini

Environmental pollution by toxic compounds affects various species of living organisms, their life cycles, and symbiotic relationships. This study investigated the host-parasite relationship between <i>Tenebrio molitor</i> Linnaeus, 1758 (Coleoptera, Tenebrionidae) and <i>Gregarina steini</i> Berthold, 1827 (Eugregarinorida, Gregarinida) under exposure to aniline, formaldehyde, and o-xylene at different concentrations. For laboratory studies, 480 larvae of <i>T. molitor</i> and five concentrations of the studied organic compounds were used. Groups of <i>T. molitor</i>, each consisting of ten individuals, were subjected to the tested compounds for 10 days following the initial weight measurement. We measured the body weight and survival rate of <i>T. molitor</i> and the number of <i>G. steini</i> in them to assess the impact of the tested organic compounds on the host-parasite relationship. For all the compounds studied, a decrease in body weight and high mortality were observed in <i>T. molitor</i> at high concentrations. The lethality of the studied organic compounds was concentration-dependent. o-Xylene showed low toxicity at lower concentrations (10.4 and 26.0 mg/kg of feed), with a survival rate of 93.3% and 86.7%, respectively. At a concentration of 10.4 mg/kg, no lethal cases in <i>T. molitor</i> were observed. At higher concentrations (78 and 104 mg/kg feed), <i>T. molitor</i> mortality significantly increased to 33.3% and 53.3%, respectively.