C-M5

Particle size distribution (Granulometry)

Administrative data

Endpoint:

particle size distribution (granulometry)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

28 March 2007 to 24 April 2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted to GLP and in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do no effect the quality of the relevant results.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2007

Report date:

2007

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 110 (Particle Size Distribution / Fibre Length and Diameter Distributions)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of distribution:

volumetric distribution

Test material

Reference

Name:

Unnamed

Type:

Constituent

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Results and discussion

Particle size

Particle size 1

Percentile:

D50

Mean:

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

Remarks on result:

other: Migrated from fields under 'Mass median diameter' as D50 percentile. No source field for Standard deviation.

Particle size 2

Percentile:

other: Not applicable

Particle size distribution at different passages

Particle size distribution at different passages 1

No.:

#1

Size:

< 100 µm

Distribution:

74 %

Particle size distribution at different passages 2

No.:

#2

Size:

< 10 µm

Distribution:

2.1 %

Particle size distribution at different passages 3

No.:

#3

Size:

< 5.5 µm

Distribution:

0.327 %

Any other information on results incl. tables

Too few particles were of a size less than 10.0 µm to allow accurate assessment of mass median aerodynamic diameter.ative sampling was ensured by rolling the sample container for approximately 10 minutes and sampling from the top, middle and bottom prior to definitive testing.

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.

Measurement	Method	Result
Proportion of test material having an inhalable particle size less than 100 µm	Sieve	74.0%
Proportion of test material having a thoracic particle size less than 10.0 µm	Cascade Impactor	2.10%
Proportion of test material having a respirable particle size less than 5.5 µm	Cascade Impactor	0.327%

Applicant's summary and conclusion

Conclusions:

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

Executive summary:

The method used to evaluate particle size disrtibution is designed to comply with that given in ‘Particle Size Distribution, Fibre Length and Diameter Distribution’, June 1996 European Commission technical guidance document, which satisfies the requirements of OECD Guideline 110.

Test material (approximately 3g) was passed into the inlet port of a Marple Miller Cascade Impactor (MSP Corporation). The cascade impactor operates at a flow rate of 60 litres/minute and make-up atmospheric air was allowed to enter the impactor around the inlet port. The impactor consists of five stages with cut-point aerodynamic diameters of 10.0, 5.5, 2.4, 1.61 and 0.307 µm, and a final glass fibre filter. Particles not deposited in the artificial throat are deposited, according to size, onto the bottom of the collection cups.  The collection cups, artificial throat, and final filter were weighed before and after the run and the weight of test material collected at each stage calculated by difference.

Particle size data acquired for the test material are shown in the following table:

Measurement		Method		Result
Proportion of test material having an inhalable particle size less than 100 µm		Sieve		74.0%
Proportion of test material having a thoracic particle size less than 10.0 µm		Cascade Impactor		2.10%
Proportion of test material having a respirable particle size less than 5.5 µm		Cascade Impactor		0.327%