Fumes, silica

Additional physico-chemical information

Administrative data

Endpoint:

other: acute and chronic aquatic effects

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Performing ecotoxicity tests on poorly water soluble substances, and in particular metals and metalloids, can be problematic. Therefore, the Transformation/Dissolution (T/D) protocol is recommended as a first tier for assessing testing requirements (OECD 2001).

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: OECD SERIES ON TESTING AND ASSESSMENT Number 29 GUIDANCE DOCUMENT ON TRANSFORMATION/DISSOLUTION OF METALS AND METAL COMPOUNDS IN AQUEOUS MEDIA

Principles of method if other than guideline:

The principle of the T/D protocol is to determine the concentration of metal elements that are released from poorly water soluble substances. These data are then compared with data that are already available for each of the elements to determine if the concentration released is above the concentration expected to cause an effect in the environment.

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Fumes, silica

EC Number:

273-761-1

EC Name:

Fumes, silica

Cas Number:

69012-64-2

Molecular formula:

SiO2

IUPAC Name:

silanedione

Constituent 2

Reference substance name:

silica fume

IUPAC Name:

silica fume

Details on test material:

Name of test material (as cited in study report high grade and low grade silicon (LGSi)
- Analytical purity: HG Silica Fume: SiO2 > 96 % (w/w) and LG Silica Fume: SiO2 > 96% (w/w)

Results and discussion

Results:

The data from the 7 day T/D test and from the 28 day T/D test have been compared with the limits recommended in the EU Risk Assessment Reports (RAR). Silica fume (high grade)
appears not to contain any impurities at concentrations that may be expected to cause acute or chronic toxicity to aquatic organisms and therefore they do not require any further ecotoxicity tests for classification purposes. According to the REACH guidance document (section R7.1.7.6), the outcomes of the transformation/dissolution tests are to be used for aquatic classification and labelling purposes and can also be used for the integration of fate parameters into the Predicted Environmental Concentration (PEC) calculations. Silica fume low grade would require further ecotox testing which are ongoing.

Applicant's summary and conclusion

Conclusions:

According to the results of the T/D protocol 7 days (acute) and 28 days (chronic) the conclusion is that silica fume high grade is not classified for the environment compartment.

Executive summary:

The Transformation/Dissolution T/D protocol applicable for poorly water soluble substances, and in particular metals and metalloids, has been performed on Silica Fume for a period of 7 and 28 days representing potential acute and chronic effects respectively. Silica fume (high grade) appears not to contain any impurities at concentrations that may be expected to cause acute or chronic toxicity to aquatic organisms and therefore they do not require any further ecotoxicity tests for classification purposes.