Registration Dossier

Administrative data

Endpoint:
nanomaterial aspect ratio/shape
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2019
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
test procedure in accordance with national standard methods with acceptable restrictions

Data source

Reference
Reference Type:
other: unpublished study report
Title:
Unnamed
Year:
2019
Report Date:
2019

Materials and methods

Principles of method if other than guideline:
Image analysis: image analysis according to REACH criteria (NanoDefine ParticleSizer)
Guidelines from NanoDefine are applied:
Method selection according to Gaillard et al., Nanoscale Adv., 2019, 1, 781
TEM image evaluation according to Verleysen et al., Materials 2019, 12, 2274; doi:10.3390/ma12142274
GLP compliance:
no
Type of method:
transmission electron microscopy
Details on methods and data evaluation:
Sample Preparation
Dispersion in butyl acetate; transfer to carbon-coated TEM-grids.

Test material

Reference
Name:
Unnamed
Test material form:
solid: nanoform

Data gathering

Instruments:
TEM: Zeiss Libra 120kV
Calibration:
no data
Reproducibility:
no data

Results and discussion

Shape description
Key result
Shape:
spherical
Remarks on result:
other: The material is assigned to the “spheroidal” shape category.
Aspect ratio
Key result
x Dimension:
2.3
St. dev.:
2.6
y Dimension:
1
Remarks on result:
other: median (D50)

Any other information on results incl. tables

Despite the median aspect ratio of 2.3:1 a significant fraction of elongated particles was found. The length distribution was therefore included in the report.

Applicant's summary and conclusion

Conclusions:
The particles have a median aspect ratio of 2,3:1.
The material is assigned to the “spheroidal” shape category. The shape is “spherical”.