Exploitation of Sewage Sludge as a Nutrient-Dense Edaphic Enhancer for Sustainable Agronomy: Assessing Ecological Consequences and Repercussions

Sewage sludge (SS) is valuable for agricultural purposes after undergoing physical, chemical, and biological treatments. Intensive agricultural methodologies necessitate substantial inputs of organic matter and nutrients to maintain soil fertility and optimize crop yields. The treatment of municipal and industrial wastewater yields nutrient-dense biosolids, which can be utilized as valuable organic fertilizers after treatment to mitigate contaminants, including xenobiotics, pathogens, and toxic substances. The presence of both macronutrients and micronutrients, along with the organic matter content, makes biosolids exceptional soil amendments for diverse crop cultivation. Historically regarded as waste due to their impurity profiles, the production of wastewater and biosolids has escalated markedly in response to demographic expansion, urbanization, and industrial growth. This trend is particularly pronounced in arid and semi-arid regions, where the application of biosolids in agricultural practices is increasing, driven by the rising costs of mineral fertilizers. Although the nutrient cycling and waste management advantages associated with biosolid application can be sustainable, economically viable, and efficient, it is imperative to meticulously assess the potential hazards posed by harmful materials, such as pathogenic microorganisms and heavy metals.