o:8481 In silico assessment of the ecotoxicological characteristics of terbuthylazine as a pollutant in surface waters en Terbuthylazine (TBA), a triazine herbicide is commonly applied in agricultural activities to eliminate weed species and optimize crop yields. Following application, the accumulated TBA can persist in the environment and contaminate water sources via surface runoff and leaching. Consequently, human exposure to TBA through food chain may lead to a range of adverse health outcomes [1]. In our research, we applied various in silico methodologies to predict the biomimetic properties of TBA and evaluate its ecotoxicological impact on living organisms [2]. Preliminary studies (ADMETlab 3) indicate a significant toxicological profile such as cancerogenity and respiratore toxicity. Activity on liver enzymes (CYP2D6), passage through the blood-brain barrier and consequent neurotoxicity and endocrine toxicity can be expected as well (ProTox 3). The predicted bioconcentration factor (assesses the potential for secondary poisoning and the risk to human health via the food chain) is 0.946. The aquatic ecotoxicity is considered through values of LC50FM=5.30 (96-hour fathead minnow 50 % lethal concentration), and LC50DM=4.22 (48-hour daphnia magna 50 % lethal concentration). The predicted oral toxicity, LD50 for TBA is 750 mg/kg (Class 4). We assessed the impact on the human body of consuming one liter of water for measured 8.2 μg/l of TBA (OPERA). Predictions show that TBA will be mostly accumulated in the liver (7.8 μg/ml) and intestines (5.3 μg/ml) which can cause liver damage. Pharmacokinetic predictions indicate a high degree of human intestinal absorption (HIA=0.894), which further increases the toxic effect of its increased concentration in the intestines. In the case of a pregnant woman, it can be expected to cross the placenta and cause liver damage (36.38 μg/ml) and kidney damage (28.25 μg/ml). There is also accumulation in the thyroid gland (13.91 μg/ml) which may lead to delayed fetal development. The obtained data indicate an important ecotoxicological risk of TBA and the possibility of toxic effects including pregnant women. 2025-11-19T11:33:27.442Z 44 no 46 Tatjana Mitrović Institute of Physics Belgrade, University of Belgrade, Belgrade, Serbia 0000-0002-5991-1445 Darija Obradović Institute of Physics Belgrade, University of Belgrade, Belgrade, Serbia person Saša Lazović Institute of Physics Belgrade, University of Belgrade, Belgrade, Serbia person Marija Perović Jaroslav Černi Water Institute, Belgrade, Serbia person 0000-0003-2045-001X application/pdf 1251355 https://unilib.phaidrabg.rs/o:8481 no yes 1 70 92000004 71A04 II Natural Hazards and Climate Change, International Conference for identifying and tackling challenges together, Szeged, 21-23 May 2025 86 Department of Physical and Environmental Geography University of Szeged, Hungary 2025