Aluminium sulphate

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:

09 March 2010- 04 June 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

This study has been performed according to OECD and EC guidelines and according to GLP principles. Test substance is adequately characterised. Therefore full validation applies.

Qualifier:

according to guideline

Guideline:

other: CIPAC MT 59: "Sieve Analysis"

Version / remarks:

Physico-chemical Methods for Technical and Formulated Pesticides; CIPAC Handbook Volume F, 1995.

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

sieving

Remarks:

dry sieve

Type of distribution:

mass based distribution

No.:

#1

Size:

< 100 µm

Distribution:

0.1 %

No.:

#2

Size:

>= 100 - < 180 µm

Distribution:

< 0.1 %

No.:

#3

Size:

>= 180 - < 250 µm

Distribution:

< 0.1 %

No.:

#4

Size:

>= 250 - < 500 µm

Distribution:

0.1 %

No.:

#5

Size:

>= 500 - < 2 000 µm

Distribution:

89 %

No.:

#6

Size:

>= 2 000 µm

Distribution:

10.9 %

Conclusions:

The sample tested has very low potential nor for inhalation, nor for dust explosion.

Executive summary:

The particle size distribution of aluminium sulphate basic hydrated was investigated according to CIPAC guideline, dry sieve method.

The fractions separated were weighted, and the mass percent distribution was calculated.

The sample tested contains mainly particles between 500 and 200 µm (89.0%), or above (10.9%).

Reference 2

Endpoint:

particle size distribution (granulometry)

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

The test substance is aluminium sulphate basic, of formula Al2 (OH)0.16 (SO4)2.92, and not pure aluminium sulphate Al2 (SO4)3; however, according to the notifier, limited basicity may occur in the technical substance. Therefore, the chemical similarity (only 0.8% OH) is considered sufficient for supporting data on the hydrated form, the reference substance for the REACh registration dossier being the anhydrous form.

Reason / purpose for cross-reference:

read-across source

No.:

#1

Size:

< 100 µm

Distribution:

0.1 %

Executive summary:

A sample of an analogue substance was found to have a very limited mass fraction of fine particles (0.1% < 100 µm).

Description of key information

Since the particle size is process-dependent, no key value can be given. The risk assessment was performed for both high and low dustiness option.

Additional information

No data is available on the reference substance (anhydrous form), but a reliable experimental study was conducted on analogue substance, showing a very limited mass fraction of fine particles (0.1% < 100 µm).

However, this study was only provided as an example to satisfy the endpoint requirement, because this physical property depends on the manufacturing process.

From the various processes of the individual registrants, particle size distribution can show different profiles, from very low amounts of inhalable particles (> 100 μm), to, on the contrary, mainly fine dust (< 25 μm).

Therefore the CSA was performed for both high and low dustiness parameter, and the individual data, considered as confidential as information on composition, are not deemed necessary.