<p>Waste valorization plays a critical role in the sustainable production of high-value materials. At the same time, the detection of environmental pollutants is essential for safeguarding both human health and ecosystems. Meeting this demand requires the development of easy to use, reliable, and highly sensitive probes for real-time environmental monitoring. Compared to chemically synthesized carbon dots (CDs), green CDs derived from renewable resources have attracted significant attention due to their unique advantages, including non-toxicity, enhanced water solubility, tunable luminescence, low cost, and excellent biocompatibility. Utilizing sustainable food waste materials and human-related biomass sources for the fabrication of CDs also contributes to the reduction of overall waste generation. This review highlights how food-waste-derived carbon dots (FW-CDs) address the growing need for cost-effective, user-friendly, and continuous environmental monitoring tools. It begins by discussing various synthesis routes, characterization techniques, and properties. The promising applications of FW-CDs in detecting contaminants such as heavy metals, pesticides, organic molecules, gases, and antibiotics are also explored. Finally, the review presents an outlook on the opportunities, potential challenges, and future prospects related to the effective utilization of renewable resources.</p> Graphical Abstract <p></p>