Since wear particles are shown to result in a bioactive response when in the micron sized range, it is thought that nano-sized particles would be relatively inert.
However the effect of their increased surface area to volume ratio cannot be ignored. As a result of their larger surface area particles are more likely to release ions. The release of ions, if toxic can result in genotoxic and cytotoxic reactions. The release of ions has been found to not be limited to metallic debris but has also been reported for ceramic wear debris.
