lambda4-cerium(4+) zirconium(4+) tetraoxidandiide

Flammability

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

substances / mixtures which in contact with water emit flammable gases

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the experience in production or handling shows that the substance does not react with water, e.g. the substance is manufactured with water or washed with water

other:

Reference 2

Endpoint:

flammable solids

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Reference 3

Endpoint:

flammable solids

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

10 June 2005 - 13 October 2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.10 (Flammability (Solids))

Version / remarks:

Cited as Directive 92/69/EEC, A.10

Deviations:

yes

Remarks:

Ignition source: use of a platinum wire heated by electrical power instead of a direct flame. This modification has no effect on the conclusion.

GLP compliance:

yes

Test procedure:

burning rate test: preliminary screening test

Remarks on result:

substance does not ignite and propagate combustion either by burning with flame or smouldering along 200 mm of the powder train within the 2 minutes test period

The test item did not burn. No further testing was required.

Interpretation of results:

GHS criteria not met

Conclusions:

Cerium dioxide is not highly flammable under the conditions of the test.

Executive summary:

The determination of the flammability of cerium dioxide was performed using a powder train about 250 mm long, according to EU Method A10.

The test item did not burn. No further testing was required. Cerium dioxide is not highly flammable under the conditions of the test.

Reference 4

Endpoint:

pyrophoric solids

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the substance is known to be stable in contact with air at room temperature for prolonged periods of time (days) and hence, the classification procedure does not need to be applied

other:

Reference 5

Endpoint:

self-heating substances / mixtures

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Reference 6

Endpoint:

flammable solids

Type of information:

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

Adequacy of study:

supporting study

Justification for type of information:

Read across from flammability data for the constituent cerium dioxide which are used as supporting information for the reaction mass of cerium dioxide and zirconium dioxide. The read across justification document is attached to IUCLID Section 13.

Reason / purpose for cross-reference:

read-across source

Test procedure:

burning rate test: preliminary screening test

Remarks on result:

substance does not ignite and propagate combustion either by burning with flame or smouldering along 200 mm of the powder train within the 2 minutes test period

Remarks:

The negative result of the flammability test on CeO2 supports the conclusion that the reaction mass of CeO2 and ZrO2 is not expected to be a flammable solid.

Description of key information

Based on the fact that both cerium and zirconium are present in their highest oxidation state (i.e. 4+), the absence of structural alerts, as well as experience in day-to-day handling and use, the reaction mass of cerium dioxide and zirconium dioxide can be concluded not to be flammable, self-heating, pyrophoric, or capable of releasing flammable gases in contact with water. Available data on the constituent cerium dioxide are used as supporting information in a read across analogue approach.

Key value for chemical safety assessment

Flammability:

not classified

Additional information

For cerium dioxide, one GLP-compliant experimental study (Cerutti, 2005), scored as Klimisch 1, is available and shows no flammable properties for this substance.

Justification for classification or non-classification

Pyrophoricity:

In the daily handling and use of the reaction mass of cerium dioxide and zirconium dioxide during which continuous exposure to air can occur, no spontaneous ignition is observed. The absence of structural alerts furthermore confirms that it is highly unlikely that the reaction mass of cerium dioxide and zirconium dioxide has pyrophoric properties. In addition, both main constituents of the reaction mass of cerium dioxide and zirconium dioxide are considered to have no pyrophoric properties.

Flammability in contact with water:

Under conditions where the reaction mass of cerium dioxide and zirconium dioxide is in contact with water no ignition and/or liberation of flammable gases is observed. The absence of structural alerts furthermore confirms that it is highly unlikely that the reaction mass of cerium dioxide and zirconium dioxide is flammable in contact with water. In addition, both main constituents of the reaction mass of cerium dioxide and zirconium dioxide are considered not to be flammable in contact with water.

Flammability:

The oxidation state of zirconium and cerium in the reaction mass of cerium dioxide and zirconium dioxide is in its highest possible state (4+). Therefore, the substance can be considered as non-flammable.

Self-heating:

The oxidation state of zirconium and cerium in the reaction mass of cerium dioxide and zirconium dioxide is in its highest possible state (4+). Therefore, the substance can be considered as non-flammable and not sensitive to self-heating.