Androst-4-ene-3,17-dione

Particle size distribution (Granulometry)

Link to relevant study record(s)

Reference

Endpoint:

particle size distribution (granulometry)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02 to 11 Aug 2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

other: ISO 13320:2009

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: CIPAC MT 187

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Principles of method if other than guideline:

- Initially observation to determine whether sieving of the material is required
- Malvern Mastersizer 2000 laser Diffraction Analyser

GLP compliance:

yes (incl. QA statement)

Type of method:

Laser scattering/diffraction

Type of distribution:

volumetric distribution

Mass median aerodynamic diameter:

74.414 µm

Geometric standard deviation:

1.35

Key result

Percentile:

D50

Mean:

78.074 µm

Remarks on result:

other: 10 % of the material is < 28.092 µm, 50 % of the material is < 68.504 µm and 90 % of material the is < 144.720 µm

Mean:

78.074 µm

Remarks on result:

other: Volume weighted mean (mean value of 5 runs)

Mean:

68.504 µm

Remarks on result:

other: Median (d.50) (mean value of 5 runs)

Mean:

72.524 µm

Remarks on result:

other: Mode (mean value of 5 runs)

Mean:

74.414 µm

Remarks on result:

other: MMAD (Mass Median Aerodynamic Diameter) (mean value of 5 runs)

Coefficient of variation for d50 is less than 3%; d10 and d90 are less than 5%. Thus repeatability of the characteristic particles in the size distribution are within the acceptable limits as per the ISO 13320-1 test standard.

 

Validity criteria for the measurement of the granulometry:

Target condition according to guideline:	Actual condition according to the study:	Validity criteria met:
Method B: The length and diameter distributions of fibres, if required, should be measured at least twice - using separate samplings and preparations - with at least 70 fibres per histogram. No two values in a given histogram interval should differ by more than 50 % or 3 fibres, whichever is larger.	Sample length measured at least twice.	Yes
Method B: Full length (1) and diameter (d) data are needed on fibres of dimensions d ≥ 0.1 µm and 1 ≥ 5 µm. Two histogram distributions, based on examination of at least 50 fibres each, should be prepared. For diameters, the ranges should be 0.1 - 0.5, 0.5 - 1.0, 1 - 2, 2 - 3, 3 – 5 µm and over 5 µm. For lengths they should be 0 - 5, 5 - 10, 10 - 15, 15 - 20, (etc.) µm.	All values are measured.	Yes
Method B: Number of particles per field and total number of fibres measured should be stated.	Number is stated.	Yes.

Conclusions:

The MMAD (Mass Median Aerodynamic Diameter < 100 ¿m) has a mean value of 74.41 ¿m for Androst-4-ene-3,17-dione.

Executive summary:

As the sample is believed to be toxic, the analysis was carried out using the `wet¿, small volume dispersion system. Several solvents were tried, in order to determine a suitable medium that provided maximum dispersability, but with minimum solubility. Silicone oil was finally selected as the most suitable dispersant. The particle size distribution was analysed over the range 0.02 µm to 2000 µm by the laser diffraction test. The median diameter (volume weighted mean) was 78.074µm. 3.89 % by volume of sample was seen to be < 10.00 µm. The MMAD (Mass Median Aerodynamic Diameter < 100 µm) has a mean value of 74.41 µm for Androst-4-ene-3,17-dione.

Description of key information

The MMAD (Mass Median Aerodynamic Diameter < 100 µm) has a mean value of 74.41 µm for Androst-4-ene-3,17-dione.

Additional information

Coefficient of variation for d50 is less than 3%; d10 and d90 are less than 5%. Thus, repeatability of the characteristic particles in the size distribution are within the acceptable limits as per the ISO 13320-1 test standard.