The toxicological impact of nanoparticles

Even though nanotechnology is a fairly new field, nanomaterials are not. Au and Ag nanoparticles (NPs) were used in Persia in the 10^th century BC to fabricate ceramic glazes to provide a lustrous or iridescent effect. This technique was then brought to Spain, where it was improved by the Moors during the 14^th century, before finally spreading throughout much of Europe. In addition, over 5000 years ago, the Egyptians ingested Au NPs for mental and bodily purification. In all cases, the users did not know that they were NPs.