Tin difluoride

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

Study period:

2015/2016

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:

Heubach dust meter connected to a cascade impactor

Principles of method if other than guideline:

The Heubach dust meter is modified in a way that a seven stage cascade impactor is connected to the system. This involves an additional air fed of 20 L/min via the coarse dust separator needed to supply the cascade impactor with 40 L/min air current as specified in the manufacturer’s specificcations.

The calculation report: EBRC, T (2016)

The Multiple-Path Particle Dosimetry Model (MPPD, v2.11; ARA, 2009) was used to predict this fractional deposition behaviour for workers.
The model algorithms calculate the deposition (and clearance) of mono-disperse and polydisperse aerosols in the respiratory tract for particles ranging from ultra-fine (0.01 microns) to coarse (20 microns) sizes. Within each airway, deposition is calculated using theoretically derived efficiencies for deposition by diffusion, sedimentation and impaction within the airway or airway bifurcation. Filtration of aerosols by the head is determined using empirical efficiency functions.

GLP compliance:

no

Type of method:

other: Heubach dust meter connected to a cascade impactor

Type of distribution:

volumetric distribution

Mass median aerodynamic diameter:

17.84 µm

Geometric standard deviation:

7.86

Remarks on result:

not measured/tested

Dustiness (airborne fraction): total: 0.7 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 monomodal lognormal distribution to the data by non-linear regression procedure. As a result, the MMAD and GSD are calculable and reported (MMAD= 17.84 µm, GSD= 7.86).

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): 40.17 %

Tracheobronchial (TB): 1.58 %

Pulmonary (PU): 4.78 %

Conclusions:

Total dustiness (airborne fraction): 0.7 mg/g (experimental results, DMT Report).

Mass median aerodynamic diamater of airborne fraction: MMAD= 17.84 µm, GSD= 7.86

Fractional deposition in human respiratory tract (MPPD model, based on calculated MMAD):
Head (ET): 40.17 %
Tracheobronchial (TB): 1.58 %
Pulmonary (PU): 4.78 %

Reference 2

Endpoint:

particle size distribution (granulometry)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2015-10-09

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)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7520 (Particle Size, Fiber Length, and Diameter Distribution)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: ISO 13320 (2009): Particle size analysis – Laser diffraction methods

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

signed 2013-03-22

Type of method:

Laser scattering/diffraction

Type of distribution:

volumetric distribution

Remarks on result:

not measured/tested

Percentile:

D10

Mean:

36.9 µm

St. dev.:

1.98

Remarks on result:

other: Mean of 6 measurements/ St.dev. was calculated from two means of three measurements

Percentile:

D50

Mean:

82.2 µm

St. dev.:

0.28

Remarks on result:

other: Mean of 6 measurements/ St.dev. was calculated from two means of three measurements

Percentile:

D90

Mean:

144.4 µm

St. dev.:

0.14

Remarks on result:

other: Mean of 6 measurements/ St.dev. was calculated from two means of three measurements

Two test series of 3 measurements each were performed with the fine fraction of the test item.

Test series 1

D10: 38.3 µm

D50: 82.4 µm (Median diameter)

D90: 144.5 µm

Test series 2

D10: 35.5 µm

D50: 82.0 µm (Median diameter)

D90: 144.3 µm

Average

D10: 36.9 µm

D50: 82.2 µm(Median diameter)

D90: 144.4 µm

Conclusions:

The test item Zinn(II)-fluorid (Sn(II)F2) has a median particle size D50 = 82 µm, which was determined by laser diffraction measurement.

Description of key information

PSD:

D10: 36.9 µm, D50: 82.2 µm, D90: 144.4 µm

Dustiness:

Total: 0.7 mg/g; MMAD= 17.84 µm, GSD= 7.86

Fractional deposition in human respiratory tract: Head (ET): 40.17 %, Tracheobronchial (TB): 1.58 %, Pulmonary (PU): 4.78 %

Additional information

PSD (Smeykal, 2015):

The test item Zinn(II)-fluorid (Sn(II)F2) has a median particle size D50 = 82 µm, which was determined by laser diffraction measurement:

D10: 36.9 µm

D50: 82.2 µm

D90: 144.4 µm

Dustiness (Gogilan & EBRC, 2016)

Total dustiness (airborne fraction): 0.7 mg/g (experimental results, DMT Report).

Mass median aerodynamic diamater of airborne fraction: MMAD= 17.84 µm, GSD= 7.86

Fractional deposition in human respiratory tract (MPPD model, based on calculated MMAD):

Head (ET): 40.17 %

Tracheobronchial (TB): 1.58 %

Pulmonary (PU): 4.78 %