[1R-(1α,4β,4aα,6β,8aα)]-octahydro-4,8a,9,9-tetramethyl-1,6-methano-1(2H)-naphthol

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:

14 November 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

equivalent or similar to guideline

Guideline:

other: European Commission 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:

sieving

Type of particle tested:

primary particle

Type of distribution:

mass based distribution

Specific details on test material used for the study:

Appearance test material: white crystalline powder

Remarks on result:

other: no MMAD and geometric standard deviation in the report

No.:

#1

Size:

100 µm

Distribution:

< 6.23 %

Remarks on result:

other: weight percentage

Table: Sieve results

Measurement	Result
Mass of test item transferred to sieve (W1)	16.46 g
Mass of test item passed through sieve (W3– W2)	0.51 g
Percentage of test item less than 100 µm	3.10%

Among the test item remaining on the sieve after testing were several large pieces (conglomerates) of test item. These pieces where not friable and clearly would not pass through the sieve or cause an inhalation hazard. Therefore, these pieces were removed, weighed together and the mass subtracted from the mass of test item used. The percentage of test item less than 100 µm was recalculated so to be based on the powdery portion of the test item sample giving a worst case scenario. The mass of the large pieces was 8.27 g. Therefore the percentage of test item passing through the 100 µm sieve based on 8.19 g of powdery test item was 6.23%. This value will be used as a limit value to represent a worst case scenario.

Conclusions:

The percentage of test item having a particle size of less than 100 µm was determined to be ≤ 6.23% w/w.

Executive summary:

The proportion of test item particles with sizes < 100 µm was determined to be 3.1% using a sieve method (GLP-compliant study). Among the test item remaining on the 100 µm sieve after testing were several large pieces (conglomerates). These pieces where not friable. After correction for this part of the test item, the percentage of test item having a particle size < 100 µm was determined to be ≤ 6.23% w/w. The test item has been considered to be essentially non-inhalable.

Description of key information

The percentage of test item having a particle size of less than 100 µm was determined to be ≤ 6.23% w/w in a GLP study using a sieve method. 

The test item has been considered to be essentially non-inhalable.

Additional information

The proportion of test item particles with sizes < 100 µm was determined to be 3.1% using a sieve method. Among the test item remaining on the 100 µm sieve after testing were several large pieces (conglomerates). These pieces where not friable. After correction for this part of the test item, the percentage of test item having a particle size < 100 µm was determined to be ≤ 6.23% w/w.