<p>Nanoparticles (NPs) especially silver nanoparticles (AgNPs) are important probe in environmental sensing because of their properties such as large surface area, size and improved chemical activity. This review focuses on the abilities of AgNPs for the detection of a number of environmental pollutants including heavy metals, dyes, emerging water contaminants, drugs, inorganic ions, and air pollutants. The physical, chemical and green synthesis of AgNPs is explained in detail where each has its unique benefits with regard to control, efficiency as well as environmentally friendly approaches. This is evident that sensors based on AgNPs presented high sensitivity and selectivity, making it possible to monitor trace levels of contaminants in different environmental compartments. The pathways through which AgNPs may come into contact with pollutants and generate an analytically recognizable signal are described and elucidated, with special reference given to green synthesis approaches. This review also discusses current and future developments of the techniques such as multi-contaminant analysis, development of portable sensors and real time environmental monitoring. The difficulties of an optimization of the green synthesis process, stability of the sensor, potential environmental and health effects of nanoparticles are discussed in detail. The last section reviews the future scope of the work proposing the integration of new synthesis methods of the two techniques and the design of new more affordable and reproducible approaches to be applied at large in the field of pollutants monitoring.</p>