<p>One of the biggest environmental challenges of contemporary times is the increasing pollution of air, soil, and water by pesticides and hazardous metals. These contaminants persist in nature, accumulating through food chains, and endangering both ecosystems and human health. Large-scale environmental monitoring is restricted by the high cost, complex operation, and lack of portability of traditional analytical techniques, which are still the gold standard for accurate detection. In recent years, electrochemical sensors have emerged as a viable and powerful alternative. They combine sensitivity, selectivity and affordability with quick and on-site measurements. This review explores the main advances in electrochemical strategies for detecting pesticides and toxic metals, along with potentiometric, amperometric, voltammetric, and impedimetric approaches, as well as new hybrid systems that integrate optical and electrochemical detection. The impact of new materials, such as nanocarbons, metal and metal-oxide nanostructures, conducting polymers, and biofunctional interfaces are specifically highlighted. Combined, these innovations have enabled the creation of devices with ultra-low detection limits, high reproducibility, and the potential for real-time environmental monitoring. The review concludes by emphasizing how these technologies are advancing from laboratory research toward real-world applications, enabling faster, easier, and more sustainable pollutant detection for environmental preservation.</p>