N-tert-butylbenzothiazole-2-sulphenamide

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

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)

Principles of method if other than guideline:

In consideration of the relevance of granulometry study on toxicological assessment, only the size distributions of the sieved fraction < 100 µm were studied in detail.

GLP compliance:

no

Type of method:

sieving

Remarks:

scanning electron microscopy

Type of distribution:

counted distribution

Specific details on test material used for the study:

- Lot no.: 9090415
- Source of sample: Flexsys SA/NV

Key result

Percentile:

D50

Mean:

91 µm

Remarks on result:

other: Migrated from fields under 'Mass median diameter' as D50 percentile. No source field for Standard deviation.

The sample was first sieved by a 100 µm sieve.

weighted sample:              3.5992 g

weight fraction < 100 µm:   0.0527 g

mass fraction < 100 µm:       1.46 %

The mass fraction < 100 µm was 1.46 %, and was investigated by scanning electron microscopy. The median aspect ratio was 1.56 with 0.45 as standard deviation.

The median diameter of the particle size is given for the fraction < 100µm. The value 91 µm was calculated for cubical and spherical paritcles.

	spherical volume	cubical volume
particle size	mass fraction	mass fraction
< 4 µm	0.12 %	0.10 %
4 - 10 µm	1.56 %	1.13 %
10 - 100 µm	67.51 %	70.38 %
> 100 µm*	30.81 %	28.39 %
median diameter	91 µm	91 µm

*Particles with diameter greater than 100 µm are due to their aspect ratios bigger than 1.75.

The particles whose aspect ratios were bigger than 1.75, passed the 100 µm sieve but were cosidered as particles with mean diameter higher than 100 µm.

Conclusions:

According to OECD guideline 110, the particle size distribution of N-tert-butyl-2-benzothiazolesulfenamide was determined by scanning electron microscopy method for the sieved fraction (< 100 µm, 1.46 % of total sample) and presented on the basis of calculated mass fractions. The median diameter was 91 µm with the main fraction of 70 % distributing in the range of 10 to 100 µm; and hence the tested N-tert-butyl-2-benzothiazolesulfenamide particles with sieved size smaller than 100 µm are mainly dominated by inhalable fraction as defined in EN 481.

Executive summary:

According to OECD guideline 110, the particle size distribution of N-tert-butyl-2-benzothiazolesulfenamide was determined by scanning electron microscopy method for the sieved fraction (< 100 µm, 1.46 % of total sample) and presented on the basis of calculated mass fractions. The median diameter was 91 µm with the main fraction of 70 % distributing in the range of 10 to 100 µm; and hence the tested N-tert-butyl-2-benzothiazolesulfenamide particles with sieved size smaller than 100 µm are mainly dominated by inhalable fraction as defined in EN 481.

Description of key information

According to OECD guideline 110, the particle size distribution of TBBS was determined by scanning electron microscopy method for the sieved fraction (< 100 µm, 1.46 % of total sample) and presented on the basis of calculated mass fractions. The median diameter was 91 µm with the main fraction of 70 % distributing in the range of 10 to 100 µm; and hence the tested TBBS particles with sieved size smaller than 100 µm are mainly dominated by inhalable fraction as defined in EN 481.

Additional information

The sample has been chosen as a worst case based on the grades which are available from the manufactures in EU.