Assessment of Emerging Contaminants in Treated Wastewater Through Plant-Based Biotests

Given the increasing concern about the presence of emerging contaminants in wastewater and their persistence in the environment, this study aimed to assess the effects of two anxiolytic pharmaceuticals commonly used in human therapy—Tranxilium (dipotassium clorazepate) and Zolpidem (zolpidem tartrate)—on plant development. Lettuce (Lactuca sativa L.) and wheat (Triticum aestivum) were selected as the biotest species. Phytotoxicity assays were also performed on Raphanus sativus. Greenhouse experiments were conducted using different concentrations of both pharmaceuticals, and several physiological and growth parameters were evaluated, including the germination rate, biomass accumulation, SPAD index, and spectrophotometrically measured contents of chlorophyll A, chlorophyll B, and carotenoids. The results indicated that both pharmaceuticals can affect plant growth, with stimulatory effects at intermediate concentrations and phytotoxic effects at higher levels. These findings highlight the importance of considering the impact of emerging contaminants on agricultural ecosystems and their potential risks to environmental and human health.