Silver or silver nanoparticles: a hazardous threat to the environment and human health?

Nanotechnology is a rapidly growing science of producing and utilizing nano-sized particles that measure in nanometers. These nanomaterials are already having an impact on health care. Now-a-days we are using nanoproducts in various fields. Of these, silver nanoparticles are playing a major role in the field of nanotechnology and nanomedicine. Their unique size-dependent properties make these materials superior and indispensable as they show unusual physical, chemical and biological properties. Silver nanoparticles have potential antimicrobial activity towards many pathogenic microbes. Along with this antimicrobial activity, silver nanoparticles are showing unacceptable toxic effects on human health and the environment. The chronic exposure to silver causes adverse effects such as permanent bluish-grey discoloration of the skin (argyria) and eyes (argyrosis). Besides argyria and argyrosis, exposure to soluble silver compounds may produce other toxic effects like liver and kidney damage, irritation of the eyes, skin, respiratory and intestinal tract and changes to blood cells. This review summarizes the hazardous effects of silver nanoparticles in the environment and theirs toxic effects on human health.