Registration Dossier

Physical & Chemical properties

Particle size distribution (Granulometry)

Administrative data

Endpoint:
particle size distribution (granulometry)
Type of information:
experimental study
Adequacy of study:
key study
Study period:
12 October 2017 - 22 November 2017
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
test procedure in accordance with generally accepted scientific standards and described in sufficient detail
Cross-reference
Reason / purpose:
reference to other study
Reference
Endpoint:
relative density
Type of information:
experimental study
Adequacy of study:
key study
Study period:
03 October 2017 - 13 October 2017
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to
Guideline:
OECD Guideline 109 (Density of Liquids and Solids)
Version / remarks:
2012
Deviations:
no
Qualifier:
according to
Guideline:
EU Method A.3 (Relative Density)
Version / remarks:
2008
Deviations:
no
Qualifier:
according to
Guideline:
EPA OPPTS 830.7300 (Density / Relative Density / Bulk Density)
Version / remarks:
2002
Deviations:
no
GLP compliance:
yes
Type of method:
air comparison pycnometer (for solids)
Specific details on test material used for the study:
TREATMENT OF TEST MATERIAL PRIOR TO TESTING
The test item was reduced by grinding using a mortar and dried in a desiccator under vacuum using silica gel as the drying agent at 19.2 ± 0.4°C and protected from light for 47 hours.
Dynamic viscosity of test material:
not applicable (substance is a solid)
Key result
Type:
relative density
Remarks:
d
Density:
1.39 other: dimensionless
Temp.:
20 °C
Remarks on result:
other: D (20°C/4°C)
Remarks:
D20/4
Key result
Type:
density
Density:
1.39 g/cm³
Temp.:
20 °C

Density of the Test Item

 

Test 1

Test 2

Mean

Density [g/cm3]

1.390

1.389

1.39

Conclusions:
The relative density D20/4 of the substance was determined to be 1.39.
Executive summary:

The relative density of the substance was determined at 20°C using a gas comparison pycnometer in a GLP study according to EC A.3, OECD 109 and OPPTS 830.7300. The relative density D20/4 was determined in duplicate, resulting in a mean value of 1.39.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2017
Report Date:
2017

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
ISO 13320 (Particle size analysis - Laser diffraction methods)
Version / remarks:
2009
Deviations:
no
Qualifier:
according to
Guideline:
other: CIPAC MT 187 (Particle size analysis by laser diffraction), Handbook K
Version / remarks:
2007
Deviations:
no
Principles of method if other than guideline:
According to REACH Article 13(3) tests on substances shall be conducted in accordance with the test methods laid down in a Commission Regulation or in accordance with other international test methods recognised by the Commission or the Agency as being appropriate. No particle size distribution test method is laid down in regulation (EC) No 440/2008. OECD 110 TG ‘Particle Size Distribution/FibreLength and Diameter Distributions’ dates from 1981 and describes two methods in detail; both methods have restrictions and are not applicable to the entire size range. ECHA’s Guidance on information requirements and Chemical Safety Assessment-Chapter R.7a stipulates that many methods are available for particle size measurements but none of them is applicable to the entire size range. The guidance mentions Laser scattering/diffraction as a method for particles of all kind and makes reference to ISO 13320:2009.
According to Guidance document EUR 20268 (2002), the laser diffraction technique is applicable to particles of respirable and inhalable size. The MMAD can be calculated.
GLP compliance:
yes (incl. certificate)
Remarks:
certificate issued: 13 January 2016 (by MHRA UK)
Type of method:
Laser scattering/diffraction
Type of particle tested:
primary particle
Type of distribution:
volumetric distribution

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder
Details on test material:
- Physical appearance: white powder with lumps
- Test item storage: at room temperature protected from light
Specific details on test material used for the study:
relative density: 1.39
The substance was tested as received.

Results and discussion

Mass median aerodynamic diameter:
16.659 µm
Remarks on result:
other: standard deviation of the population = 0.133 µm (0.8%)
Particle sizeopen allclose all
Key result
Percentile:
D10
Mean:
7.749 µm
St. dev.:
0.077
Remarks on result:
other: st.dev. of the population
Key result
Percentile:
D50
Mean:
14.13 µm
St. dev.:
0.113
Remarks on result:
other: st.dev. of the population
Key result
Percentile:
D90
Mean:
24.644 µm
St. dev.:
0.248
Remarks on result:
other: st.dev. of the population
Particle size distribution at different passages
No.:
#1
Size:
< 10 µm
Distribution:
22.92 other: vol%

Any other information on results incl. tables

VISUAL OBSERVATION

- The substance was observed (by eye) to be a a fine powder which formed into many clusters and lumps.

- At magnification under a microscope using 3.2 objective lens, the particles appeared to be irregular shapes crystals. The smallest individual particle size was approximately < 10 μm and the largest individual size was approximately 38 μm.

- At magnification under a microscope using 40 objective lens, the sample was observed to be made up of single crystalline particles.

DISPERSANT TRIALS

- water: substance not soluble but sample clumped together

- acetone: soluble

- methanol: soluble

- kerosene: substance not soluble and sample well dispersed (for at least 120 minutes; concentrations tested: 1.5 and 5.0 mg/30 mL)

LASER DIFFRACTION ANALYSIS

Coefficient of variation for D50 is < 3%; D10 and D90 are < 5%. These values are within the acceptable limits mentioned in the ISO 13320 standard.

volume weighted mean = 15.353 μm

mode = 14.531 μm

Applicant's summary and conclusion

Conclusions:
Particle size distribution of the substance: D10= 7.749 µm, D50= 14.13 µm and D90= 24.644 µm. 22.92% by volume was determined to be smaller than 10 µm.
The MMAD was determined to be 16.659 µm.
Executive summary:

The particle size distribution of the substance was determined using laser diffraction analysis (small volume wet module) in a GLP study according to ISO 13320 and CIPAC MT 187.

Each result is the average of five runs:

D10= 7.749 µm, D50= 14.13 µm and D90= 24.644 µm.

22.92% by volume was determined to be smaller than 10 µm.

The MMAD was determined to be 16.659 µm.