8 Challenges of the treatment technologies 
The influence of wastewater treatment on biophysical ecosystems and living creatures poses considerable issues. Regulations controlling waste management are not the only elements influencing these difficulties; socioeconomic and regional considerations also play a role. It is challenging to find a universal technique that will remove every contaminant from wastewater. Many biological, physical and chemical treatments have been developed and published in the last three years (Barakat, 2011; Rathoure, 2015). Although wastewater treatment technologies are crucial for reducing pollution, they face several serious obstacles. The intricate and varied makeup of wastewater is a significant problem that can reduce the efficacy of treatment processes (Köhler et al., 2018). Emerging contaminants which include drugs, personal care items, and microplastics are difficult for conventional methods to remove and require sophisticated treatment methods that are frequently expensive and energy-intensive (Drewes et al., 2016). Managing the residuals and byproducts produced during treatment presents another difficulty. For example, advanced oxidation processes (AOPs) and membrane technologies can generate hazardous byproducts or concentrated waste streams that need additional handling or disposal, increasing operational complexity (Parsons & Jefferson, 2006). Membrane fouling is a recurring issue in membrane-based technologies, necessitating frequent maintenance and replacement, which raises operational costs (Li et al., 2017). Similarly, the high energy requirements of procedures like electrocoagulation and reverse osmosis raise concerns regarding the sustainability and carbon footprint of wastewater treatment (Shannon et al., 2008). Furthermore, there are budgetary and logistical difficulties in integrating new technologies into existing treatment facilities. Modernizing infrastructure to support novel treatments frequently necessitates a large financial outlay, and maintaining these cutting-edge systems calls for qualified staff (Chen et al., 2015). Further research and regulation are necessary to ensure the safe application of emerging treatment technologies, as their potential impacts on human health and the environment, such as the use of nanomaterials, are not yet fully understood (Qu, Alvarez, & Li, 2013).
9. Future Directions
Emerging contaminants (ECs) present a significant challenge for water treatment systems due to their presence in trace quantities. Although physical, chemical, biological, and hybrid treatment processes have proven effective for many ECs, complete removal remains elusive. Consequently, several promising research directions are suggested to address this issue, including: