Pollution of aquatic systems and habitats by heavy metals is a significant concern to the ecosystem and health of humans
as it arises from different sources, including industrial discharges, agricultural activities, mining activities, and disposal of
toxic substances. Heavy metals introduced in water bodies may also come through leachates from contaminated soils and
sediments. Subsequent bioaccumulation in marine organisms and spheres of life around lakes, rivers, and oceans is inevitable
upon their introduction. Recently, some studies have shed light on nano-waste biomass (NWB), which can be deliberately
used to remove heavy metal ions from polluted waters. It is produced from eco-friendly agro-industrial and is treated on
the nanometer scale, which enhances adsorption because its size has increased, increasing its surface area and active sites
for binding. This novel technology deals with heavy metal pollution and waste management, as it helps recycle unwanted
materials into useful adsorbents, thereby minimizing incinerators and reducing tree cuts. Metal ions from water can be
removed through adsorption, where NWB is bonded to metal ions. NWB has been acknowledged as an economically viable
and environmentally benign means of decontamination. Advanced analytical methods, such as X-ray diffusion, field emission
scanning electron microscopy, high-resolution transmission electron microscopy, and others, were used for the extensive
characterization of NWB. The lemon peel nanoparticles exhibited a particle size range of 40 nm–65 nm. Additionally, a
few experiments about contact time and pH were performed to improve NWB adsorption and increase NWB efficiency in
eradicating heavy metal ions from polluted water sources.