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:
10 March 2008
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Study conducted in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affcet the quality of relevant results.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2008

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 110 (Particle Size Distribution / Fibre Length and Diameter Distributions)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Remarks:
Date of inspection: 21/08/07 Date of signature: 15/10/07
Type of method:
sieving
Type of distribution:
other: not stated in report

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Details on test material:
Sponsor's identification : VCBK3810
Description : black powder
Lot number : N006746
Date received : 25 February 2008
Storage conditions : room temperature, in the dark

Results and discussion

Particle size
Percentile:
D50
Remarks on result:
other: Migrated from fields under 'Mass median diameter' as D50 percentile. No source field for Standard deviation.
Particle size distribution at different passagesopen allclose all
No.:
#1
Size:
< 100 µm
Distribution:
67.3 %
No.:
#2
Size:
< 10 µm
Distribution:
<= 3.75 %
No.:
#3
Size:
< 5.5 µm
Distribution:
<= 2.27 %

Any other information on results incl. tables

 Results:

Screening test (sieve method):

The results of the sieving procedure are shown in the following table:

Sieve aperture size (µm)

100

Mass of test material transferred to sieve (g)

11.40

Mass of test material passed through sieve (g)

7.67

Test material less than sieve aperture size (%)

67.3

 


 Definitive test (cascade impactor method):

Determination 1:

The results of the cascade impactor method are shown in the following table:

 Determination 1

Cup Number

ParticleCollected (µm)

Cup Masses (g)

Pre-sampling

Post-sampling

Difference

1

>10.0

86.0752

89.3044

3.2292

2

5.5 - 10.0

85.4457

85.4501

0.0042

3

2.4 - 5.5

85.8864

85.8880

0.0016

4

1.61 - 2.4

85.5895

85.5904

0.0009

5

0.307 - 1.61

85.7493

85.7501

0.0008

Filter

<0.307

0.1174

0.1178

0.0004

Amount of test material found in artificial throat: 0.0 g.
Total amount of test material recovered from impactor cups, filter and artificial throat: 3.2373 g.

The cumulative amounts found for the individual particle size cut-points (µm) are shown in the following table:

Determination 1:

Cup Number

Particle Size Cut-points (µm)

Cumulative Mass of Test Material (g)

Cumulative Amount of Test Material (%)

2

10.0

0.0081

0.250

3

5.5

0.0037

0.114

4

2.4

0.0021

6.5 x 10-2

5

1.61

0.0012

3.7 x 10-2

Filter

0.307

0.0004

1.2 x 10-2

Determination 2:

The results of the cascade impactor method are shown in the following table:

Determination 2:

Cup Number

ParticleCollected (µm)

Cup Masses (g)

Pre-sampling

Post-sampling

Difference

1

>10.0

86.0501

89.4252

3.3751

2

5.5 - 10.0

85.4263

85.4656

0.0393

3

2.4 - 5.5

85.8648

85.8833

0.0185

4

1.61 - 2.4

85.5690

85.5844

0.0154

5

0.307 - 1.61

85.7331

85.7442

0.0111

Filter

<0.307

0.1140

0.1164

0.0024

Amount of test material found in artificial throat: 0.1 g.
Total amount of test material recovered from impactor cups, filter and artificial throat: 3.5618 g.

The cumulative amounts found for the individual particle size cut-points (µm) are shown in the following table:

Determination 2

Cup Number

Particle Size Cut-points (µm)

Cumulative Mass of Test Material (g)

Cumulative Amount of Test Material (%)

2

10.0

0.0867

2.43

3

5.5

0.0474

1.33

4

2.4

0.0289

0.811

5

1.61

0.0135

0.379

Filter

0.307

0.0024

6.7 x 10-2

 


Determination 3:

The results of the cascade impactor method are shown in the following table:

Determination 3:

Cup Number

ParticleCollected (µm)

Cup Masses (g)

Pre-sampling

Post-sampling

Difference

1

>10.0

86.0416

89.3816

3.3400

2

5.5 - 10.0

85.4128

85.4656

0.0528

3

2.4 - 5.5

85.8554

85.8799

0.0245

4

1.61 - 2.4

85.5534

85.5803

0.0269

5

0.307 - 1.61

85.7140

85.7397

0.0257

Filter

<0.307

0.1144

0.1184

0.0040

Amount of test material found in artificial throat: 0.1 g.
Total amount of test material recovered from impactor cups, filter and artificial throat: 3.5739 g.

The cumulative amounts found for the individual particle size cut-points (µm) are shown in the following table:

Determination 3:

Cup Number

Particle Size Cut-points (µm)

Cumulative Mass of Test Material (g)

Cumulative Amount of Test Material (%)

2

10.0

0.1339

3.75

3

5.5

0.0811

2.27

4

2.4

0.0566

1.58

5

1.61

0.0297

0.831

Filter

0.307

0.0040

0.112

The overall cumulative amounts of test material with a particle size less than 10.0 µm (%) from Determinations 1 to 3 are shown in the following table:

Determination

Cumulative Amount of Test Material

Less Than 10.0 µm (%)

Mean Cumulative Amount of Test Material Less Than 10.0 µm (%)

1

0.250

<3.75

2

2.43

3

3.75

The overall cumulative amounts of test material with a particle size less than 5.5 µm (%) from Determinations 1 to 3 are shown in the following table:

Determination

Cumulative Amount of Test Material

Less Than 5.5 µm (%)

Mean Cumulative Amount of Test Material Less Than 5.5 µm (%)

1

0.114

<2.27

2

1.33

3

2.27

Discussion:

Too few particles were of a size less than 10.0 µm to allow accurate assessment of mass median aerodynamic diameter.

Representative sampling was ensured by rolling the sample container for approximately 10 minutes and sampling from the top, middle and bottom prior to definitive testing. However, as a gradient in the particle size distribution was observed for the three samples, limit values have been reported based on the bottom sampling position to represent a worst case scenario for risk assessment of the test material.

The inhalable fraction is defined as the mass fraction of particles which can be inhaled by nose or mouth, the thoracic fraction is defined as the mass fraction of particles that passes the larynx and the respirable fraction is defined as the mass fraction of particles that reaches the alveoli.


Applicant's summary and conclusion

Conclusions:
The substance contains particles (< 100µm) that may be inhalable by nose and mouth. The percenatge of particles having a particle size less than 10µm is not considered significant.
Executive summary:

Particle Size Distribution:

Particle size data have been acquired using a procedure designed to comply with the European Commission technical guidance document 'Particle Size Distribution, Fibre Length and Diameter Distribution' (June 1996), which satisfies the requirements of OECD Guideline 110. The results are as follows:

Measurement

Method

Result

Proportion of test material having an inhalable particle size less than 100 µm

Sieve

67.3%

Proportion of test material having a thoracic particle size less than 10.0 µm

Cascade Impactor

< 3.75%

Proportion of test material having a respirable particle size less than 5.5 µm

Cascade Impactor

< 2.27%

The substance contains particles (< 100µm) that may be inhalable by nose and mouth. The percenatge of particles having a particle size less than 10µm is not considered significant.