Toxicity tests of exposure to sildenafil, dicloxacillin, and ibuprofen of Eisenia fetida

Due to their extensive and ongoing use, inappropriate disposal, and partial removal in wastewater treatment facilities, pharmaceutical compounds have become major environmental contaminants. These compounds are commonly found in surface and wastewater, and pharmaceuticals can build up in the terrestrial environment when contaminated water is used again for soil replenishment or agricultural irrigation. The possible ecotoxicological effects on soil organisms, especially invertebrates, which are essential to preserving soil health and ecosystem functioning, are a cause for concern in light of this phenomenon. Three pharmaceutical substances: ibuprofen, dicloxacillin, and sildenafil, were chosen for this study due to their high rates of consumption, accessibility, and environmental significance. Ecotoxicity tests were performed following Economic Cooperation and Development Protocol 207, using Eisenia fetida as a study organism, to evaluate the impact of emerging contaminants from the pharmaceutical subgroup sildenafil, dicloxacillin, and ibuprofen. The study included both contact tests in Petri dishes and tests with artificial soil to assess the lethal concentration 50 (LC50) of these substances. The results indicated that ibuprofen exhibited the highest toxicity of the three tested pharmaceuticals, demonstrating significantly more lethal effects on Eisenia fetida in both types of tests than the other two substances evaluated. The LC50 values obtained in the study were 7.53 µg/cm2 and 65.24 mg/kg for ibuprofen, 27.34 µg/cm2 and 665.23 mg/kg for sildenafil, and 141.07 µg/cm2 and 699.44 mg/kg for dicloxacillin. These findings highlight the potential environmental risks posed by these substances and underscore the necessity for further research and regulation to mitigate their ecological impact. Ibuprofen exhibited acute toxicity at lower concentrations than sildenafil and dicloxacillin in both soil and contact tests. Contact tests showed greater sensitivity than artificial soil tests, revealing a more pronounced toxic response in the exposed organisms.