(4R)-2-oxo-1,3-oxazolidine-4-carboxylic acid

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:

other: European Commission Technical Guidance Document EUR 20268

Version / remarks:

Determination of Particle Size Distribution, Fibre Length and Diameter Distribution of Chemical Substances (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

Mass median aerodynamic diameter:

10.6 µm

Geometric standard deviation:

2.51

Remarks on result:

not measured/tested

Table 1: details on aerosol concentrations

Stage	Percentage of sample collected on each stage Trial number
	1	2	3	Mean
1	18.5	6.6	17.1	14.1
2	20.0	6.6	24.4	17.0
3	28.3	26.2	31.7	28.7
4	24.4	39.3	14.6	26.1
5	4.4	8.2	6.1	6.2
6	3.9	4.9	3.7	4.2
7	0.5	6.6	2.4	3.2
8	0.0	1.6	0.0	0.5
Filter	0.0	0.0	0.0	0.0
MMAD	12.6	7.1	12.8	10.6
Geometric standard deviation	2.12	2.42	2.49	2.51

 

Generation of aerosol concentrations of the test substance using the SAG generation device was variable, it was noted during generation that the belt speed was often variable due to the test item blocking the belt movement. This resulted in inconsistent achieved aerosol concentrations.

Conclusions:

The mean achieved mass median aerodynamic diameter of the substance, determined by casade impaction, was 10.6 μm and in the range of 7.1 μm to 12.8 μm, with a geometric standard deviation of 2.51.

Executive summary:

The particle size distribution of the substance was determined under GLP by cascade impaction in accordance with European Commission Technical Guidance Document EUR 20268, Determination of Particle Size Distribution, Fibre Length and Diameter Distribution of Chemical Substances (2002).

The particle size distribution of the test substance was determined by cascade impaction at a target aerosol concentration of 2.0 mg/L. The study was performed in a flow through snout-only chamber. A solid aerosol generator was used to generate the aerosols for the test. The SAG mechanism technique for the dispersion of dry dust and powders comprises two steps, the continuous supply of material to the disperser and the dispersal of the material as an aerosol. The method for metering powder to the disperser was to use a moving toothed belt. A regulated flow of compressed air conducted the aerosol to the inhalation chamber. The test system was housed in a ventilated cabinet. Aerosols were collected with glass microfibre filters, held in an open faced filter holder. The sample volume was measured by a wet-type gas meter. The sample analysis was done by gravimetry. The particle size distribution and mass median aerodynamic diameters (MMAD) were determined by cascade impaction. Stainless steel substrates and glass microfibre final stage filter were used. MMAD and geometric standard deviation were calculated by linear regression of the probit of the cumulative percentage, by mass, of particles smaller than the effect cut-off diameter (ECD) of each stage versus the logarithm of the ECD of each stage. Generation of aerosol concentrations of the test substance using the SAG generation device was variable, it was noted during generation that the belt speed was often variable due to the test item blocking the belt movement. This resulted in inconsistent achieved aerosol concentrations.

Description of key information

MMAD = 10.6 μm; geometric standard deviation = 2.51 (GLP, EUR 20268)