Dose metrics assessment for differently shaped and sized metal-based nanoparticles

Area of Science:

• Environmental toxicology
• Nanomaterial science
• Risk assessment

Background:

• Mean primary diameter is the standard metric for spherical nanoparticle toxicity.
• This metric is inadequate for nonspherical nanoparticles.
• A new metric is needed for accurate nanoparticle dose assessment.

Purpose of the Study:

• To determine the optimal dose metric for nanoparticle toxicity.
• To compare nanoparticle volume, surface area, and number as dose metrics.
• To evaluate dose metrics for various nanoparticle shapes and compositions.

Main Methods:

• Utilized mean surface area to volume ratio for spherical and nonspherical nanoparticles.
• Assessed toxicity in vivo (9 organisms) and in vitro (6 cell lines).
• Analyzed nanoparticle number versus effect concentration curves.

Main Results:

• Nanoparticle volume was the most appropriate dose metric for most organisms.
• Nanoparticle surface area was the best metric for silver nanoparticles in 3 organisms.
• The optimal dose metric varied based on organism and nanoparticle properties.

Conclusions:

• The choice of dose metric is critical for accurate nanoparticle risk assessment.
• Nanoparticle volume is often the most suitable metric, but exceptions exist.
• Future research should consider organism-specific and material-specific factors in dose metric selection.