Cerium(3+) acetate

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:

03 July 2017 to 27 July 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

other: European Commission Technical Guidance Document EUR 20268 'Determination of Particle Size Distribution, Fibre Length and Diameter Distribution of Chemical Substances’

Version / remarks:

2002

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

cascade impaction

Type of particle tested:

primary particle

Type of distribution:

mass based distribution

No.:

#1

Size:

< 100 µm

Distribution:

41.1 %

No.:

#2

Size:

< 10 µm

Distribution:

0.884 %

No.:

#3

Size:

< 5.5 µm

Distribution:

0.191 %

Table 2: Table to show the results of the sieving procedure

Measurement	Result
Mass of test material transferred to sieve (W1)	18.67 g
Mass of test material passed through sieve (W3 – W2)	7.67 g
Percentage of test material less than 100 μm	41.1 %

 

Table 3: Table to show the cumulative amounts of test material collected in the three determinations for the individual particle size cut-points in the cascade impactor.

Particle Size Cut Points (µm)	Cumulative mass (g)			Cumulative Percentage (%)
	Determination 1	Determination 2	Determination 3	Determination 1	Determination 2	Determination 3
<10.0	0.0356	0.0199	0.0243	1.21	0.649	0.796
<5.5	0.0078	0.0039	0.0055	0.265	0.127	0.180
<2.4	0.0029	0.0014	0.0019	0.098	0.046	0.062
<1.61	0.0007	0.0001	0.0002	0.024	0.003	0.007
<0.307	0.0000	0.0001	0.0000	0.000	0.003	0.000

 

Table 4: Summary of Results

Measurement	Method	Result
Percentage of test material with an inhalable particle size <100 μm	Sieve	41.1 %
Percentage of test material with a thoracic particle size <10.0 μm	Cascade Impactor	0.884 %
Percentage of test material with a respirable particle size <5.5 μm	Cascade Impactor	0.191 %

- Sampling for the cascade impactor determinations was performed by rolling the test material container for approximately 10 minutes then sampled from the top, middle and bottom. The overall results from the cascade impactor were taken as limit values due to the variation between the sampling positions; this gives a worst case scenario. Too few particles were of a size less than 10.0 μm to allow accurate assessment of the mass median aerodynamic diameter

- 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.

Conclusions:

Under the conditions of the study the percentage of test material with an inhalable particle size <100 μm was 41.1 %, the percentage of test material with a thoracic particle size <10.0 μm was 0.884 % and the percentage of test material with a respirable particle size <5.5 μm was 0.191 %.

Executive summary:

The particle size distribution of the test material was determined in accordance with the European Commission Guidance Document EUR 20268 ‘Determination of Particle Size Distribution, Fibre Length and Diameter Distribution of Chemical Substances’ (2002), under GLP conditions using the sieving method and cascade impactor.

In the sieving screening test an aliquot (18.76 g) of test material was added to a 100 μm sieve fitted onto a receiver pan of known mass. The percentage of test material having an inhalable particle size of less than 100 μm was determined to be 41.1 % in the screening test.

Sampling for the cascade impactor determinations was performed by rolling the test material container for approximately 10 minutes then sampling it from the top, middle and bottom. The overall results from the cascade impactor were taken as limit values due to the variation between the sampling positions; this gives a worst case scenario. Too few particles were of a size less than 10.0 μm to allow accurate assessment of the mass median aerodynamic diameter. 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.

Under the conditions of the study the percentage of test material with an inhalable particle size <100 μm was 41.1 %, the percentage of test material with a thoracic particle size <10.0 μm was 0.884 % and the percentage of test material with a respirable particle size <5.5 μm was 0.191 %.

Description of key information

Fox (2017)

Under the conditions of the study the percentage of test material with an inhalable particle size <100 μm was 41.1 %, the percentage of test material with a thoracic particle size <10.0 μm was 0.884 % and the percentage of test material with a respirable particle size <5.5 μm was 0.191 %.

Additional information

Fox (2017)

The particle size distribution of the test material was determined in accordance with the European Commission Guidance Document EUR 20268 ‘Determination of Particle Size Distribution, Fibre Length and Diameter Distribution of Chemical Substances’ (2002), under GLP conditions using the sieving method and cascade impactor. The study was awarded a reliability score of 1 in accordance with the criteria set forth by Klimisch et al. (1997).

In the sieving screening test an aliquot (18.76 g) of test material was added to a 100 μm sieve fitted onto a receiver pan of known mass. The percentage of test material having an inhalable particle size of less than 100 μm was determined to be 41.1 % in the screening test.

Sampling for the cascade impactor determinations was performed by rolling the test material container for approximately 10 minutes then sampling it from the top, middle and bottom. The overall results from the cascade impactor were taken as limit values due to the variation between the sampling positions; this gives a worst case scenario. Too few particles were of a size less than 10.0 μm to allow accurate assessment of the mass median aerodynamic diameter. 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.

Under the conditions of the study the percentage of test material with an inhalable particle size <100 μm was 41.1 %, the percentage of test material with a thoracic particle size <10.0 μm was 0.884 % and the percentage of test material with a respirable particle size <5.5 μm was 0.191 %.