3-hydroxy-2-methyl-4-pyrone

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:

from 29 November 2017 to 30 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

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

ISO 13320 (Particle size analysis - Laser diffraction methods)

Version / remarks:

2009

Qualifier:

according to guideline

Guideline:

other: CIPAC MT 187 (Particle size analysis by laser diffraction)

Version / remarks:

Handbook K, 2007

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. QA statement)

Type of method:

Laser scattering/diffraction

Type of particle tested:

primary particle

Type of distribution:

volumetric distribution

Mass median aerodynamic diameter:

352.5 µm

Geometric standard deviation:

>= 1.729 - <= 1.741

Remarks on result:

other: MMAD is the mean (n= 5) value. 'St.dev.' in table below is the population standard deviation [µm].

Key result

Percentile:

D10

Mean:

144.727 µm

St. dev.:

0.395

Key result

Percentile:

D50

Mean:

293.779 µm

St. dev.:

1.633

Key result

Percentile:

D90

Mean:

555.873 µm

St. dev.:

5.27

No.:

#1

Size:

< 10 µm

Distribution:

0 other: vol%

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.

 

VISUAL OBSERVATION

The substance was observed to be a coarse and medium white powder. Using a 3.2 objective lens, the particles appeared to be irregular shaped crystals. The smallest individual particle size was approximately 32 μm and the largest individual size was approximately 736 μm. Using a 402 objective lens, the sample was observed to be made up of single crystalline particles.

Conclusions:

Particle size distribution of the substance: D10= 145 µm, D50= 294 µm and D90= 556 µm. 0% by volume was determined to be smaller than 10 µm. The MMAD was determined to be 352.5 µm.

Executive summary:

The particle size distribution of the substance was determined using laser diffraction analysis (dry powder module) in a GLP study according to ISO 13320 and CIPAC MT 187. Each result is the average of five runs. D10= 145 µm, D50= 294 µm and D90= 556 µm. 0% by volume was determined to be smaller than 10 µm. The MMAD was determined to be 352.5 µm.

Description of key information

The particle size distribution of the substance was determined using laser diffraction analysis (dry powder module) in a GLP study according to ISO 13320 and CIPAC MT 187. Each result is the average of five runs. D10= 145 µm, D50= 294 µm and D90= 556 µm. 0% by volume was determined to be smaller than 10 µm. The MMAD was determined to be 352.5 µm.