Nowadays, environmental pollution is one of the major worldwide problems. There are various types of pollutants (i.e., organic, inorganic, and biological materials), which can contaminant water resources, land, and air. Therefore, there is a high demand to develop and design new devices for the detection and determination of various contaminants in the environment. In this regard, the chemical and biological sensors are interesting tools for environmental applications. Recently, different types of chemical and biological sensors, such as electrochemical, fluorescence, and mass-based (bio)sensors, have been developed through the studies of researchers in the many fields of science by chemists, chemical engineers, physicists, etc. Among the developed sensors and biosensors, the electrochemical ones have many advantages, including low cost, easy to fabrication and use, ability to miniaturization, and application in the point-of-demand. Furthermore, the electrochemical biosensors have been classified as the electrochemical immunosensors, aptasensors, and genosensors, which have high selectivity and sensitivity toward the proposed targets, with an emphasis on opportunities for further improvement in contaminants diagnostics and monitoring. Considering these conditions, the main approach of this review is on the electrochemical immunosensors, aptasensors, and genosensors, which have been applied in the determination of various contaminants, including organophosphorus, toxic hydrocarbons and organic compounds, heavy metals, and toxic anions and cations. The figures of merits of some important studies and related data such as LOD, LDR, and electrochemical methods, which have been used to determination of contaminants as well as the (bio)sensor design, are presented in the tables to further comparison and information.
