Zirconium dioxide or zirconia is one of the most widely used ceramic oxides. Its applications range from use in abrasive products, dental bridges and crowns, additive in paints and lacquers, in fuel cell membranes and in joint implants. Zirconium dioxide is also utilised as white pigment for porcelain or in a mixture with vanadium oxide as yellow pigment. Most consumers associate the material with ceramic kitchen knives found in many households nowadays and their blades are made of zirconia.
Most products on the market are manufactured based on micro-crystalline zirconium dioxide powders, only niche markets have started to increasingly use powers of zirconium dioxide nanoparticles.
How can I come into contact with this material?
In general, there is very little chance to come into contact with zirconium dioxide particles since these are firmly embedded in plastics or other materials. Looking at medical applications the picture changes completely. Dental prosthesis and joint implants are made of zirconia ceramics and in addition, zirconium dioxide is added as contrast agent to bone cements for radiology purposes during surgical procedures.
Is there any risk from this material to humans and the environment?
Zirconium dioxide has been proven to have excellent compatibility with bones and the surrounding connective tissue. Likewise zirconium dioxide nanoparticles are non-toxic to other environmental organisms such as bacteria, algae and zebra fish.
There is little chance of coming into contact with free zirconium dioxide nanoparticles particles as only very few applications make use of this material in nanoscaled form. Zirconium dioxide ceramics were recognised a long time ago to be highly suitable for bone implants. Many studies have been performed and confirm an excellent compatibility of zirconium dioxide with human tissues.
By the way…
- Zirconia crystals (so-called cubic zirconia) are used as diamond imitations for jewellery since zirconium dioxide has, similar to real diamonds, a high refractive index.