Risk Assessment of Manufactured Nanomaterials - Environmental and Human Health Impacts of Nanotechnology - page 409

substance

fibres granulates powders

Light microscope
examination or 100 µ m sieve

Light microscope examination

Are particles <100 µ m?

N Y

Virtually no
particles <100

Particles <100 µ m

µ m

SEM
TEM

Image analysis

Determine relative
density and water
solubility

Stop testing

N Y

Are particles soluble?

Water insoluble Water soluble

Investigate particles using
microscopy, sedimentation,
electrical sensing, and laser
doppler velocimetry

Investigate particles using
microscopy, sedimentation,
and laser doppler

Is
inhalation risk study
required?

N

Stop testing

Y

Can mass
median aerodynamic diameter
demonstrate no inhalation
risk?

Y

N

Oral route for
toxicity testing

Inhalation route
for toxicity testing

Methods: Cascade, Laser,
Rotating drum and
Continuous drop method

Figure 10.A.2 Determination of particle size distribution and morphology under REACH.