## 1 Introduction  
The emerging contaminants (ECs) are a wide range of chemical compounds, such as pharmaceuticals, personal care products (PCPs), industrial chemicals, and microplastics, that have been detected in diverse environments, especially in aquatic ecosystems [1]. In recent years, the scientific community has focused on these compounds due to a lack of regulation, a scarcity of data on their environmental presence, fate, and toxicological effects, and potential to cause adverse ecological impacts [2]. These contaminants reach the environment mainly through wastewater treatment plant effluents, agricultural runoff, and industrial discharges, and their removal in conventional treatment systems is often ineffective [3, 4], resulting in their persistence and possible bioaccumulation in the food chain. The presence of ECs in aquatic ecosystems can induce adverse effects in aquatic organisms, such as hormonal alterations, reproductive toxicity, and the development of antibiotic resistance, compromising biodiversity and ecological stability [5; 6]. In addition, human exposure to these contaminants through the consumption of contaminated drinking water and aquatic products poses potential health risks, including endocrine disruption and other toxic effects [7]. Global antibiotic consumption has experienced a sustained increase in recent decades, mainly due to its intensive use in human medicine, livestock farming, and aquaculture [8]. This consumption pattern has led to an increasingly frequent presence of antibiotics in aquatic environments, since many of them are not completely eliminated during conventional wastewater treatment [9]. Sulfamethoxazole (SMX, C\({}_{10}\)H\({}_{11}\)N\({}_{3}\)O\({}_{3}\)S), a broad-spectrum sulfonamide antibiotic, is among the most frequently detected pharmaceuticals in surface waters and represents a growing environmental concern. In a study conducted in Spain, SMX was found in 100% of surface water samples, with concentrations ranging from 4.1 to 119.3 ng/L [10], highlighting its widespread presence. This concern stems from the high environmental persistence of SMX, as it is resistant to degradation and can remain in surface water, groundwater, and even treated effluents, limiting the efficacy of conventional wastewater treatment processes. Its extensive application in both human and veterinary medicine, particularly in combination with trimethoprim as co-trimoxazole, further contributes to its continuous release into aquatic ecosystems via excretion and improper disposal. Even at low concentrations, SMX can induce ecotoxicological effects, such as oxidative stress, liver damage, and immune dysfunction in aquatic species like _Oreochromis niloticus_[11], and it can disrupt microbial communities essential for ecosystem functioning. Moreover, SMX poses a significant risk in promoting the development and spread of antibiotic-resistant bacteria and resistance genes, with aquatic environments serving as reservoirs for such resistance. Although SMX has a low bioaccumulation potential, its interaction with other pharmaceuticals may amplify its ecological impact. These findings underscore the urgent need to enhance wastewater treatment technologies and implement systematic monitoring of antibiotics in aquatic environments to mitigate their adverse effects on both environmental and human health [12; 13; 14]. To address the problem of emerging pollutants in aquatic environments, the search for more advanced and specific treatment technologies has been promoted [15; 16]. Advanced Oxidation Processes (AOPs) have been proposed as effective solutions due to their ability to generate highly reactive species, mainly hydroxyl radicals (HO\({}^{\bullet}\)), which can degrade a wide range of complex organic compounds until their complete mineralization [17; 18; 19]. These processes include diverse techniques such as Fenton oxidation, photocatalysis, ozonation, catalytic wet oxidation, and electrooxidation [20].