Organic waste (OW) generated by human activity is continuously increasing worldwide. Agriculture generates large amounts of OW derived mostly from livestock farming and agroindustries. Substantial amounts of OW are produced in areas with limited land availability, e.g. due to the concentration of animal production systems. Furthermore, OW flows are increasing as a result of urban development-wastewater, sludge and municipal waste may be treated to different degrees in industrialized and developing countries. These wastes are often applied on cultivated lands on the outskirts of cities. OW are sources of organic matter that may increase soil fertility and reduce the need for chemical fertilizers, thus enhancing sustainable agricultural production. They may also carry pollutants and repeated application on the same fields may lead to an accumulation of mineral or metallic pollutants, thus degrading the soil quality and possibly boosting the risk of pollutant transfer to the harvested plants.