Abstract

Several anthropogenic activities, chemical manufacturing, mining, nuclear waste, painting, metal processing, agricultural activities, cosmetic products and industrial activities are associated with heavy metal contamination in the wastewater. Heavy metals, such as arsenic, cadmium, chromium, lead mercury and nickel, are nonbiodegradable and highly toxic. They can directly or indirectly enter the food chain and cause several health issues, such as cancer, liver and kidney, asthma and mental retardation. Analytical methods such as inductively coupled plasma mass spectrometry (ICP-MS), atomic absorption spectroscopy (AAS), ultraviolet-visible spectroscopy and chromatography are widely used for heavy metal monitoring in heavy metal contaminations. These methods provide a sufficient level of sensitivity and selectivity, but these methods are costly, time-consuming and require sample preparation. Currently, biosensors are considered an alternative to conventional heavy metal monitoring methods due to high sensitivity, selectivity, inexpensiveness and simplicity. Herein, the authors report several biosensors and their application in monitoring heavy metal contaminations.