2,4-bis[N'-(4-methylphenyl)ureido]toluene

Particle size distribution (Granulometry)

Administrative data

Endpoint:

particle size distribution (granulometry)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

April 28, 2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

ISO 13320 (Particle size analysis - Laser diffraction methods)

Version / remarks:

1999

Principles of method if other than guideline:

According to REACH Article 13(3) tests on substances shall be conducted in accordance with the test methods laid down in a Commission Regulation or in accordance with other international test methods recognised by the Commission or the Agency as being appropriate. No particle size distribution test method is laid down in regulation (EC) No 440/2008. OECD 110 TG ‘Particle Size Distribution/FibreLength and Diameter Distributions’ dates from 1981 and describes two methods in detail; both methods have restrictions and are not applicable to the entire size range. ECHA’s Guidance on information requirements and Chemical Safety Assessment-Chapter R.7a stipulates that many methods are available for particle size measurements but none of them is applicable to the entire size range. The guidance mentions Laser scattering/diffraction as a method for particles of all kind and makes reference to ISO 13320. The MMAD can be calculated when density is known.

GLP compliance:

yes (incl. QA statement)

Type of method:

Laser scattering/diffraction

Type of particle tested:

primary particle

Type of distribution:

volumetric distribution

Test material

Test material information

Constituent 1

Reference substance name:

2,4-bis[N'-(4-methylphenyl)ureido]toluene

EC Number:

411-790-5

EC Name:

2,4-bis[N'-(4-methylphenyl)ureido]toluene

Cas Number:

54390-87-3

Molecular formula:

C23H24N4O2, C24H34N4O2

IUPAC Name:

3-(2-methyl-3-{[(4-methylphenyl)carbamoyl]amino}phenyl)-1-(4-methylphenyl)urea; 3-(2-methyl-5-{[(4-methylphenyl)carbamoyl]amino}phenyl)-1-(4-methylphenyl)urea; 3-{2-methyl-3-[(octylcarbamoyl)amino]phenyl}-1-(4-methylphenyl)urea

Test material form:

solid: particulate/powder

Details on test material:

- Name of test material (as cited in study report): KY-MA
- Batch No.: 4BT079M
- Expiration date of the batch: February 14, 2004
- Appearance: white to light pink powder
- Storage condition of test material: at room temperature in the dark

Specific details on test material used for the study:

Relative density: 1.22

Results and discussion

Mass median aerodynamic diameter:

468 µm

Particle size

Particle size 1

Key result

Percentile:

D10

Mean:

47.12 µm

St. dev.:

3.44

Particle size 2

Percentile:

D25

Mean:

187.8 µm

St. dev.:

3.44

Particle size 3

Key result

Percentile:

D50

Mean:

423.8 µm

St. dev.:

3.44

Particle size 4

Percentile:

D75

Mean:

643.6 µm

St. dev.:

3.44

Particle size 5

Percentile:

D90

Mean:

784.4 µm

St. dev.:

3.44

Particle size distribution at different passages

Size:

< 10 µm

Distribution:

3.09 %

Remarks on result:

other: average of 3 runs

Any other information on results incl. tables

Manual sieve analysis

Sieve Size (μm)	Weight (g)			By weight [%]
	Sieve	Sieve & Powder	Powder
>1000	369.0	395.1	26.1	26.1
850-1000	378.5	384.7	6.2	6.2
<850	242.0	309.7	67.7	67.7

Laser diffraction particle size analysis (sample tested: < 850 µm)

	RUN 1	RUN 2	RUN 3	Average
Volume %	100.0	100.0	100.0	100.0
Mean (µm)	284.8	285.7	254.4	274.5
Median (µm)	440.2	438.4	391.7	423.8
Mode (µm)	716.7	716.7	716.7	716.7
95% Conf. Limit (µm)	26-3120	26.2-3110	21.4-3030	24.4-3090
S.D.	3.39	3.38	3.54	3.44

Applicant's summary and conclusion

Conclusions:

Manual sieve analysis showed that 67.7% (w/w) of the substance had a particle size of < 850 μm. Laser diffraction results for the substance fraction < 850 µm:
D10 = 47.12 µm, D50 = 423.8 µm and D90= 784.4 µm. 3.09 % by volume was determined to be < 10.00 μm. The MMAD was calculated to be 468 µm.

Executive summary:

According to BS ISO 13320-1: 1999 and GLP principles the particle size distribution of the substance was determined using laser diffraction analysis

(dry powder module). Manual sieving was performed on 1000 and 850 µm sieves. 67.7% (w/w) of the substance had a particle size of < 850 μm. Laser diffraction results for the substance fraction < 850 µm:

D10 = 47.12 µm, D50 = 423.8 µm and D90= 784.4 µm. 3.09 % by volume was determined to be < 10.00 μm. The MMAD was calculated from D50 and density to be 468 µm.