Miristalkonium chloride

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:

December 19, 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 110 (Particle Size Distribution / Fibre Length and Diameter Distributions - Method A: Particle Size Distribution (effective hydrodynamic radius)

Deviations:

not specified

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7520 (Particle Size, Fiber Length, and Diameter Distribution)

Deviations:

not specified

Qualifier:

according to guideline

Guideline:

ISO 13320 (Particle size analysis - Laser diffraction methods)

Deviations:

not specified

GLP compliance:

yes (incl. QA statement)

Type of method:

other: Laser scattering/diffraction and sieving

Type of particle tested:

primary particle

Type of distribution:

volumetric distribution

Mass median aerodynamic diameter:

ca. 35.6 µm

Geometric standard deviation:

ca. 0.11

Remarks on result:

other: median particle size of the fine fraction

Key result

Percentile:

D10

Mean:

ca. 10.8 µm

St. dev.:

0.5

Key result

Percentile:

D50

Mean:

ca. 35.6 µm

St. dev.:

0.11

Key result

Percentile:

D90

Mean:

ca. 106.5 µm

St. dev.:

0.1

No.:

#1

Size:

< 250 µm

Distribution:

ca. 35.1 %

No.:

#2

Size:

< 200 µm

Distribution:

ca. 34.9 %

No.:

#3

Size:

< 100 µm

Distribution:

ca. 31 %

No.:

#4

Size:

< 50 µm

Distribution:

ca. 22.4 %

No.:

#5

Size:

< 10 µm

Distribution:

ca. 2.9 %

Results

 

Particle Size Distribution

Two test series of 3 measurements each were performed with the fine fraction of the test substance.

 

Test series 1:

D₁₀: 11.2 µm

D₅₀: 36.6 µm (Median diameter)

D₉₀: 106.4 µm

 

Test series 2:

D₁₀: 10.3 µm

D₅₀: 34.5 µm (Median diameter)

D₉₀: 106.5 µm

 

Average

D₁₀: 10.8 µm

D₅₀: 35.6 µm (Median diameter)

D₉₀: 106.5 µm

 

Final Results

The test substance has a coarse fraction with a particle size of >2000 µm of 64.9 % and a fine fraction with a particle size <2000 µm of 35.1 %. The fine fraction has a median particle size D₅₀ = 36 µm, which was determined by laser diffraction measurement. According to the results of the laser diffraction measurement and the sieving, the test substance contains particles with a size of <250 µm of 35.1 %, with a size of <200 µm of 34.9 %, with a size of <100 µm of 31.0 %, with a size of <50 µm of 22.4 % with a size of <10 µm of 2.9 %.

Conclusions:

Under the study conditions, the particle size distribution of the test substance was found to be: 65% > 2000 µm and 35% < 2000 µm (35%<250 µm; 35% of <200 µm; 31% <100 µm; 22.4% <50 µm), 2.9% < 10 µm. The median particle size (D50) of the fine particles were determined to be 36 µm.

Executive summary:

A study was conducted to determine the particle size distribution of the test substance, C14 ADBAC, using laser scattering/diffraction method, according to the OECD Guideline 110, EPA OPPTS 830.7520 and ISO 13320, in compliance with GLP. Before the measurements, the test substance was sieved through a 2000 um sieve and the coarse fraction (with a particle size of >2000 µm) was found to be 64.9% and a fine fraction (with a particle size <2000 µm) was found to be 35.1%. The fine fraction was determined to have a median particle size D50 = 36 µm, which was determined by laser diffraction measurement. The mean D10, D50 and D90 (distribution type: volume) diameters applying the Fraunhofer particle model were determined to be 10.8, 35.6 and 106.5 µm respectively. According to the results of the laser diffraction measurement and the sieving, the test substance contains particles with a size of <250 µm of 35.1%, with a size of <200 µm of 34.9%, with a size of <100 µm of 31.0%, with a size of <50 µm of 22.4% with a size of <10 µm of 2.9%. Under the study conditions, the particle size distribution of the test substance was found to be: 65% > 2000 µm and 35% <2000 µm (35% <250 µm; 35% of <200 µm; 31% <100 µm; 22.4% <50 µm), 2.9% <10 µm. The median particle size (D50) was determined to be 36 µm (Moller, 2018).

According to R.7c Guidance, in humans, particles with aerodynamic diameters below 100 μm have the potential to be inhaled. Particles with aerodynamic diameters below 50 μm may reach the thoracic region and those below 15 μm the alveolar region of the respiratory tract. Therefore, based on the results of the study, about 90% of the substance, have a particle size >100 µm, hence are not available as inhalable fraction. Only around 8%, with a particle size <50 µm (median diameter of 36 µm), may reach the thoracic region and around 3%, may reach the alveolar region of the respiratory tract.

Description of key information

Particle size distribution of the test substance was determined using laser scattering/diffraction and sieving methods, according to the OECD Guideline 110, (Moller, 2018).

Additional information

Particle size distribution: 65% > 2000 µm and 35% < 2000 µm (35% <250 µm; 35% of <200 µm; 31% <100 µm; 22.4% <50 µm), 2.9% < 10 µm; median particle size (D50) of fine fraction: 36 µm