Orthoperiodic acid

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:

08 June 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

ISO 13320 (Particle size analysis - Laser diffraction methods)

Version / remarks:

2009

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

Laser scattering/diffraction

Mass median aerodynamic diameter:

3 291 µm

Geometric standard deviation:

0.011

Key result

Percentile:

D10

Mean:

1 080 µm

St. dev.:

30.1

Key result

Percentile:

D50

Mean:

1 790 µm

St. dev.:

10.5

Key result

Percentile:

D90

Mean:

2 760 µm

St. dev.:

10.5

OPTICAL MICROSCOPE ANALYSIS

- Standard visual observation: Sample observed to be a coarse, gritty, free flowing, non-dusting off-white powder.

- Observation using 3.2 objective lens: The particles appeared to be irregular shaped crystals. The smallest individual particle size was approximately 752 μm and the largest individual size was approximately 1888 μm.

- Observation using 40 objective lens: The sample was observed to be made up of single crystalline particles.

  

PRELIMINARY SOLUBILITY TEST

The sample was well dispersed in silicone oil. For the full solubility and dispersability test silicone oil was selected.

 

SOLUBILITY AND DISPERSABILITY TEST

The test material sample was well dispersed in the silicon oil at 10 seconds and 30, 60, 90 and 120 minutes.

The sample proved to be insoluble and well dispersed in silicone oil. Silicone oil was therefore used as the dispersant.

 

LASER DIFFRACTION PARTICLE SIZE ANALYSIS

Table 1: Full Test Results

	Run 1	Run 2	Run 3	Run 4	Run 5	Average **
Volume weighted mean	1840	1850	1860	1860	1890	1860
Median	1780	1780	1790	1790	1820	1790
Mode	1890	1890	1900	1900	1910	1900
MMAD*	3259	3266	3293	3289	3348	3291
d10 (10 % of material is <)	1060	1060	1090	1080	1130	1080
d50 (50 % of material is <)	1780	1780	1790	1790	1820	1790
d90 (90 % of material is <)	2750	2750	2760	2760	2780	2760

All results are in μm

* Mass median aerodynamic diameter

** Average result is calculated from the entirety of data captured in each run and is not a simple arithmetic mean.

0.0  

 

Table 2: Standard Deviation results 

	Run 1	Run 2	Run 3	Run 4	Run 5	STDVP	% STDVP
d10 (10 % of material is <)	1060	1060	1090	1080	1130	30.1	2.78
d50 (50 % of material is <)	1780	1780	1790	1790	1820	19.2	1.07
d90 (90 % of material is <)	2750	2750	2760	2760	2780	10.5	0.380
GSD	1.429	1.427	1.417	1.418	1.397	0.011	0.8
MMAD	3259	3266	3293	3289	3348	31.460	1.0

GSD = Geometric standard deviation of the lognormal particle size distribution (calculated from d50/d15.78)

STDVP = standard deviation of the population

% STDVP = percentage standard deviation of the population

 

- 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.

Conclusions:

Under the conditions of this study, the MMAD (mass median aerodynamic diameter) of the test material was 3291 µm, the d10, d50 and d90 values were 1080, 1790 and 2760 µm, respectively. 0.00 % of the test material sample was < 10.00 µm.

Executive summary:

The particle size distribution of the test material was investigated in accordance with the standardised guideline ISO 13320, under GLP conditions.

Following optical microscope analysis and solubility and dispersability tests the laser diffraction analysis was conducted using the small volume (wet) module (SVM) with silicone oil as the dispersant.

Under the conditions of this study, the MMAD (mass median aerodynamic diameter) of the test material was 3291 µm, the d10, d50 and d90 values were 1080, 1790 and 2760 µm, respectively. 0.00 % of the test material sample was < 10.00 µm.

Description of key information

Livingston (2018)

Under the conditions of this study, the MMAD (mass median aerodynamic diameter) of the test material was 3291 µm, the d10, d50 and d90 values were 1080, 1790 and 2760 µm, respectively. 0.00 % of the test material sample was < 10.00 µm.

Additional information

Livingston (2018)

The particle size distribution of the test material was investigated in accordance with the standardised guideline ISO 13320, under GLP conditions. The study was awarded a reliability score of 1 in accordance with the criteria set forth by Klimisch et al. (1997).

Following optical microscope analysis and solubility and dispersability tests the laser diffraction analysis was conducted using the small volume (wet) module (SVM) with silicone oil as the dispersant.

Under the conditions of this study, the MMAD (mass median aerodynamic diameter) of the test material was 3291 µm, the d10, d50 and d90 values were 1080, 1790 and 2760 µm, respectively. 0.00 % of the test material sample was < 10.00 µm.

Read-across to Sodium Periodate

The particle size distribution of the read across substance, sodium periodate, was evaluated in accordance with OECD Guideline 110 under GLP conditions. The study was assigned a reliability score of 1 in accordance with the principles for assessing data quality as outlined by Klimisch et al (1997), however, since the data is available on a read across substance an overall reliability score of 2 is considered appropriate. Sodium periodate is considered to be a suitable substance for read across since it is the sodium salt of periodic acid.

During the study the proportion of a sample that was able to pass through a 100 µm sieve was measured; the proportion of test material having an inhalable particle size of less than 100 µm was determined to be 2.9 %.

Therefore, the test material was considered to be essentially non-inhalable.