European Commission Seeks Input On Safety Of Nanomaterials Used In Medical Devices

By Nick Otto

The European Commission’s Scientific Committee on Emerging Newly Identified Health Risks (SCENIHR) has opened public consultation on the use of nanomaterials in medical devices.

The Guidance on the Determination of Potential Health Effects of Nanomaterials Used in Medical Devices seeks to provide information for risk assessments that need to be considered when evaluating the safety of devices using nanomaterials.

“The use of nanomaterials in medical devices poses a challenge for the safety evaluation and risk assessment of these medical devices as the specific character of the nanomaterial used should be taken into consideration,” the guidance notes.

According to the guidance, there is a “need for special considerations in relation to the safety evaluation of nanomaterials, in view of the possible distinct properties, interactions, and/or effects that may differ from conventional forms of the same materials.”

SCENIHR is recommending a phased approach “based on potential release and characteristics of the nanomaterials.”

In the first phase, an evaluation is recommended to gauge the potential of a device to release nanoparticles either directly or due to wear and tear of the device during use. The guidance adds that if the nanomaterial is fully embedded in the device, then evaluating the wear potential of the device would be sufficient.

Exposure routes for patients include inhalation, oral, dermal and mucosal, the guidance adds. 

The second phase of evaluation is aimed at determining the effect of distribution of any particles released. This testing would include determining a nanoparticle’s “persistence potential” — or how long a particle can remain in a particular tissue — and the amount of toxicity testing required for the given particle and length of exposure.

If it is concluded that it is unlikely that the particles could enter the systemic circulation even under realistic worst-case conditions, then a very limited toxicity testing protocol is needed, with a general limit to the effects at the contact site.

For invasive devices, a more detailed study of the potential of the particles to access and remain in specific tissues is required by toxicokinetic studies.

In the third phase, hazard would be assessed by selecting toxicity tests that are relevant based on the nature of the observed exposure and potential persistence in specific organs.

The committee hopes that as knowledge of nanoparticles improves, prediction of the nature, distribution, tissue levels, and potential persistence of particles will become clearer.

Comments on this guidance are due Oct. 3.