What are nanomaterials?
Nanomaterial means a natural, incidental or manufactured material containing particles, in an unbound state or as an aggregate or as an agglomerate and where, for 50 % or more of the particles, one or more external dimensions is in the size range 1 nm-100 nm. Nanomaterials also include fullerenes, graphene flakes and single wall carbon nanotubes with one or more external dimensions below 1 nm.
Properties and applications
Nanomaterials are increasingly used in medical devices. The small size of nanoparticles causes the properties of nanomaterials to differ from those of a larger particle size material of the same chemical composition. Nanomaterials are used to improve the mechanical, biological and chemical properties of devices, for example. However, no comprehensive scientific evidence on the risks and benefits of nanomaterials is yet available.
There is a wide range of different nanomaterials, and new materials are being actively developed. Examples of the use of nanomaterials in medical devices include the use of carbon nanotubes in bone cement, nano-polymeric materials in dental fillings, the use of nanosilver as an antibacterial agent in wound dressings, and various nanocoatings used in the sensing elements of in vitro diagnostic devices.
Regulation of the use of nanomaterials
The increasing use of nanomaterials has also increased the regulation of their use. The EU regulation on medical devices (2017/745) contains specific requirements for medical devices containing nanomaterials. The Regulation requires to reduce the risks linked to the size and the properties of particles which are or can be released into the user's body. In the design and manufacture of devices, manufacturers must take special care when using nanoparticles. Such devices must be subject to the most stringent conformity assessment procedures. According to the new classification rules (MDR, Annex XIII, Rule 19), all devices incorporating or consisting of nanomaterial are classified as class III if they present a high or medium potential for internal exposure; class IIb if they present a low potential for internal exposure; and class IIa if they present a negligible potential for internal exposure.