2-[[1-[[(2,3-dihydro-2-oxo-1H-benzimidazol-5-yl)amino]carbonyl]-2-oxopropyl]azo]benzoic acid

Nanomaterial dustiness

Administrative data

Endpoint:

nanomaterial dustiness

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods

Remarks:

according to DIN EN 17199-3

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2021

Report date:

2021

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: DIN EN 17199-3

Version / remarks:

measurement of dustiness of bulk materials that contain or release respirable NOAA or other respirable particles - Part 3: Continuous drop method

Deviations:

yes

Remarks:

1 meaurement performed

GLP compliance:

no

Type of method:

continuous drop

Sampling:

The test material was used without further treatment (e.g. drying). 34.8 g (141.5 cm3) test material are used for the measurement, dosing rate: 3.48 g/min

Test material

Test material information

Constituent 1

Reference substance name:

2-[[1-[[(2,3-dihydro-2-oxo-1H-benzimidazol-5-yl)amino]carbonyl]-2-oxopropyl]azo]benzoic acid

EC Number:

250-830-4

EC Name:

2-[[1-[[(2,3-dihydro-2-oxo-1H-benzimidazol-5-yl)amino]carbonyl]-2-oxopropyl]azo]benzoic acid

Cas Number:

31837-42-0

Molecular formula:

C18H15N5O5

IUPAC Name:

2-({2-oxo-1-[(2-oxo-2,3-dihydro-1H-benzimidazol-5-yl)carbamoyl]propyl}diazenyl)benzoic acid

Test material form:

solid: nanoform

Results and discussion

Dustiness index

Dustiness index 1

Key result

Mean:

26 691.2 other: 1/mg

Remarks on result:

other: dustiness index as number of airborne particles per mg in the nanoscale (10 nm - 100 nm)

Dustiness index 2

Mean:

1 752.6 other: N/cm3

Remarks on result:

other: number of airborne nanoparticles per cm3

Any other information on results incl. tables

measurement duration: 10 min

temperature: 25.6°C, rel. air humidity 25 %

The cleaned, almost particle-free air had a total particle count of 6 particles/cm³ in the range of 10 nm - 417 nm, the nanoscale fraction (10 - 100 nm) contained 3 particles/cm³.

table 1: summary SMPS (sanning mobility particle sizer)

Range [nm]	Mean [nm]	Concentration [N/cm^3]	ICD[1/mg]	ECD[1/mg x s]
10 - 100	41.1	1752.6	26691.2	44.5
100 - 417	178.4	438.9	6685.0	11.1
10 - 417	68.6	2191.5	33376.3	55.6

I_CD: dustiness index as number of airborne particles per mg

E_CD: emission rate as number of particles per mg per second

mean: average particle diameter in nm

N: number of airborne particles

table 2: summary OPS (optical particle sizer)

Range [µm]	Mean [µm]	Concentration [N/cm^3]	ICD[1/mg]	ECD[1/mg x s]
0.3 - 10	4.4	13.9	212.4	0.4

Applicant's summary and conclusion

Executive summary:

The dusting behaviour of the test material was investigated using DIN EN 17199 -3: 2019 -12 "workplace exposure - measurement of dustiness of bulk materials that contain or release respirable nano objects and their aggregates and agglomerates or other respirable particles- Part 3: Copntinuous drop method".

The dust released by the falling test material was measured by a scanning mobility particle sizer (SMPS, 10 - 417 nm) and an optical particle sizer (3 - 10 µm). The counterflow was provided by cleaned, almost particle-free air.

The SMPS counted 2191.5 particles per cm³ (in the nanoscale (10 - 100 m) 1752.6 particles per cm³) corresponding to a dustiness index of 33376.3 particles per mg (in the nanoscale (10 - 100 nm) 26691.2 particles per mg). The mean size of the nanoparticles was 41.1 nm, the mean size of particles in the range 10 - 417 nm was 68.6 nm.

The OPS (0.3 - 10 µm) counted 13.9 particles per cm³ corresponding to a dustiness index of 212.4 particles per mg. The mean size of the particles was 4.4 µm.