Glyphosate is the most widely used active ingredient of Glyphosate Based Herbicides (GBHs), and which has environmental mobility towards water by its physicochemical characteristics. These properties determine its low availability in living organisms (log K_ow < 0), which is increased by the presence of co-adjuvant activators in GBHs and its biodegradation (metabolites). Eco-toxicological studies have determined that glyphosate affects to several aquatic trophic-levels (freshwater/marine environments), being more toxics GBHs. Therefore, its potential environmental risk has promoted the development of conventional (biological and physicochemical) and non-conventional (Advanced-Oxidation-Processes or AOPs, combined processes) treatment strategies. Biological processes will generate incomplete degradation (metabolites generation), and variable removal efficiencies (25–99%). Physicochemical processes will be efficient (approx. 90%) but transferring the glyphosate from water to the adsorbent material (dangerous waste generation). Currently, AOPs will arise as a rapid (minutes) and effective alternative for glyphosate removal (>90%), depending on operational conditions, and without generation of intermediate metabolites. Moreover, new strategies (electrochemical) will avoid the hazardous waste production. Other combined processes (biological + physicochemical) will also reach glyphosate efficiencies removal above 90% but needing large spaces. However, their physical characteristics would make them feasible to be applied in agricultural areas.

Emerging contaminants (ECs) are causing negative effects on the environment and even on people, so their removal has become a priority worldwide. Adsorption and the associated technologies where this process occurs (filtration/biofiltration) have gained great interest, due to its low cost, easy operation, and effectiveness mainly in the removal (up to 100%) of lipophilic ECs (log K_ow > 4). Activated carbon continues to be the most efficient material in the removal of ECs (>850 mg/g). However, other conventional materials (activated carbon, clays, zeolites) and non-conventional materials (agro-industrial/forestry/industrial residues, nanomaterials, among others) have shown efficiencies greater than 90%. Adsorption depends on the physicochemical properties of the materials and ECs. Thus, physical/chemical/thermal modifications and nanomaterial synthesis are the most used procedures to improve adsorption capacity. A material with good adsorptive properties could be used efficiently in filtration/biofiltration technologies. Agro-industrial residues are promising alternatives to be used in these technologies, due to their high availability, low toxicity, and adsorption capacities (up to 350 mg/g). In filtration/biofiltration technologies, the material, in addition to acting as adsorbent, plays a fundamental role in operation and hydraulics. Therefore, selecting the appropriate material improves the efficiency/useful life of the filter/biofilter.

Chile is an agricultural power, but also one of the most vulnerable countries to climate change and water shortage. About 50% of the irrigated agriculture land in Chile is in the central zone, thanks to its agricultural-climatic characteristics that provide an adequate water supply (100–4000 m³/s). However, the vulnerability scenario in this zone is high due to the seasonal availability of water resources. Therefore, opportunities to use non-conventional alternative sources (e.g., wastewater) become an appealing and feasible option due to the high population and animal density (>76%) in this part of the country. Moreover, the physicochemical characteristics of the municipal and livestock wastewater suggest that there are potential opportunities to recycle nutrients for agricultural production. In Chile, wastewater reuse opportunities are noted by the wide coverage of wastewater treatment programs, with municipal and intensified livestock production taking up most of the percentage (>99%). Nevertheless, more than 70% of wastewater treatment systems reach biological secondary treatment, which suggests reuse possibilities only for non-food crops. Therefore, this paper is focused on a preliminary analysis of the potential of reusing and recycling municipal and livestock wastewater for Chilean agriculture. There is some reuse work occurring in Chile, specifically in the use of municipal and livestock wastewater for cereal crops (animal feed), forests, and grasslands. However, aspects related to the long-term effects of these practices have not yet been evaluated. Therefore, municipal and livestock wastewater in Chile could be re-valued in agriculture, but the current quality and condition of treated wastewater do not ensure its safe use in food crops. In addition, state policies are needed to provide sustainability (circular and ethic economy) to water reusing/recycling in agriculture.