Fatty acids, C8-10, zinc salts

Particle size distribution (Granulometry)

Link to relevant study record(s)

Reference

Reference 1

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:

DIN 55992-1 (Determination of a parameter for the dust formation of pigments and extenders - Part 1: Rotation method)

Version / remarks:

2006

Deviations:

yes

Remarks:

A Heubach dust meter was connected to a seven stage cascade impactor.

GLP compliance:

no

Type of method:

rotating drum method

Remarks:

connected to a cascade impactor

Type of distribution:

volumetric distribution

Specific details on test material used for the study:

- Storage condition of test material: at room temperature in the original container

Mass median aerodynamic diameter:

21.66 µm

Geometric standard deviation:

1.96

Percentile:

D50

Remarks on result:

not measured/tested

Dustiness (airborne fraction): total: 412.10 mg/g.

In the original study report by DMT, a calculation of the mass median diameter was not conducted. Since the deposited fractions were provided for each of the cascade impactor stages, it was possible to fit a mono modal lognormal distribution to the databy standard non-linear regression procedure. As a result, the MMAD and GSD of total dustiness (airborne) fraction are calculable and reported (MMAD = 21.66 µm, GSD = 1.96). As the cascade impactor already takes aerodynamic characteristics of the particles into account, the reported mass median diameter can be interpreted as the mass median aerodynamic diameter.

This figure and the corresponding GSD were used as distribution parameters for the MPPD model enabling an estimation of deposited dust fractions in the human respiratory tract: These fractions were estimated as follows:

Head (ET): 59.1 %

Tracheobronchial (TB): 0.3 %

Pulmonary (PU): 0.3 %

Conclusions:

Total Dustiness (airborne fraction): 412.10 mg/g (experimental results, DMT Report).

Mass median aerodynamic diameter of total dustiness (airborne) fraction: MMAD = 21.66 µm (distribution fitted to cascade impactor data).
Geometric standard deviation of MMAD: GSD = 1.96

Fractional deposition in human respiratory tract (MPPD model, based on calculated MMAD):
Head (ET): 59.1 %
Tracheobronchial (TB): 0.3 %
Pulmonary (PU): 0.3 %

Reference 2

Endpoint:

particle size distribution (granulometry)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2009-02-03 to 2009-03-16

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

other: EUR 20268 EN (2002, Entwurf)

Deviations:

no

GLP compliance:

no

Type of method:

Laser scattering/diffraction

Type of distribution:

volumetric distribution

Remarks on result:

not measured/tested

Percentile:

D10

Mean:

4.51 µm

St. dev.:

0.29

Remarks on result:

other: Average of four measurements

Percentile:

D50

Mean:

18.75 µm

St. dev.:

1.32

Remarks on result:

other: Average of four measurements

Percentile:

D90

Mean:

37.85 µm

St. dev.:

2.18

Remarks on result:

other: Average of four measurements

	Measurement				Average
	No.1	No. 2	No. 3	No. 4
%- contingent of 0-2.6 µm	5.27 %	5.19 %	5.80 %	5.58 %	5.5 %
%- contingent of 0-5.00 µm	12.25 %	10.16 %	11.41 %	11.21 %	11.3 %
%- contingent of 0-10.50 µm	27.32 %	21.41 %	25.32 %	26.68 %	25.2 %
%- contingent of 0-30.00 µm	79.11 %	75.79 %	79.13 %	83.33 %	79.5 %
%- contingent of 0-103.00 µm	100.00 %	100.00 %	100.00 %	100.00 %	100.00 %
Median diameter
D 10%	4.23 µm	4.92 µm	4.39 µm	4.50 µm	4.5 µm
D 50%	18.02 µm	20.58 µm	18.78 µm	17.60 µm	18.7 µm
D 90%	38.93 µm	39.59 µm	38.18 µm	34.70 µm	37.9 µm

The density is independent from the particle size, that is why the procentual distribution of the volume and mass are identical.

Conclusions:

The D 10, D 50 and D 90 of the particle size distribution of fatty acids, C8-10, zinc salts are 4.5 µm, 18.7 µm and 37.9 µm, respectively.

Description of key information

The granulometry of a representative sample of Fatty acids, C8-10, zinc salts is:
Particle size distribution (Schenkenberg 2009)
D10: 4.5 µm
D50: 18.7 µm
D90: 37.9 µm

Dustiness (Parr, Grewe, 2012)
- Total Dustiness (airborne fraction): 412.10 mg/g .
- Mass median aerodynamic diamater of airborne fraction: MMAD = 21.66 µm (distribution fitted to cascade impactor data).
- Geometric standard deviation of MMAD: GSD = 1.96
- Fractional deposition in human respiratory tract (MPPD model, based on calculated MMAD):
Head (ET): 59.1 %
Tracheobronchial (TB): 0.3%
Pulmonary (PU): 0.3%

Additional information

The D10, D50 and D90 of the particle size distribution of a representative test material are 4.5 µm, 18.7 µm and 37.9 µm, respectively.

The total dustiness (airborne fraction) was determined according to method DIN 55992-1:2006 using a modified Heubach dust meter.

Total dustiness is 412.10 mg/g.

MMAD of the total dustiness fraction is 21.66 µm (GSD 1.96).

These were used as distribution parameters for the MPPD model enabling an estimation of deposited dust fractions in the human respiratory tract: These fractions were estimated as follows:

Head (ET): 59.1 %

Tracheobronchial (TB): 0.3%

Pulmonary (PU): 0.3%