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

Oxidising properties

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

oxidising solids

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

from 10 jun 2005 to 13 Oct 2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.17 (Oxidising Properties (Solids))

Version / remarks:

Cited as Directive 92/69/EEC, A.17

Deviations:

yes

Remarks:

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

GLP compliance:

yes

Contact with:

powdered cellulose

Sample tested:

other: test item / cellulose mixtures containing 10 to 90% test item in 10% increment weight

Parameter:

mean burning time

Remarks on result:

other: The test item did not burn.

Preliminary test:

Reference mixture (barium nitrate / cellulose - ratio 2/1) took 89 seconds to burn.

The combustion of the substance mixture (test item / cellulose - ratio 2/1) stopped immediately.

 

Main study:

Nominal proportion of test item (%)	Weight of cellulose (g)	Weight of Test item (g)	Burning time (s) / Remarks
10	13.547	1.511	Ignition by the hot wire, but no flame propagation
20	11.975	2.953	Ignition by the hot wire, but no flame propagation
30	10.524	4.465	Ignition by the hot wire, but no flame propagation
40	9.016	5.974	Ignition by the hot wire, but no flame propagation
50	7.479	7.558	Ignition by the hot wire, but no flame propagation
60	5.999	9.033	Ignition by the hot wire, but no flame propagation
70	4.485	10.487	Ignition by the hot wire, but no flame propagation
80	2.955	11.972	Ignition by the hot wire, but no flame propagation
90	1.488	13.509	Ignition by the hot wire, but no flame propagation

 

The test item did not burn.

CERIUM DIOXIDE has no oxidising properties under the conditions of the test.

Interpretation of results:

GHS criteria not met

Conclusions:

Cerium dioxide has no oxidising properties under the conditions of the test.

Executive summary:

The determination of the oxidising properties of cerium dioxide was performed according to EU Method A17 using a powder train about 250 mm long. The test item was mixed with a combustible substance, being powdered cellulose. The test item / cellulose mixtures contained 10-90% test item in 10% increment by weight. As a reference, a barium nitrate / cellulose mixture was prepared. A pile of each mixture was ignited with the hot wire, and the burning time was recorded. No flame propagation was observed with each mixture of test item and cellulose. So cerium dioxide has no oxidising potential.

Reference 2

Endpoint:

oxidising 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 incapable of reacting exothermically with combustible materials

Reason / purpose for cross-reference:

data waiving: supporting information

Reference 3

Endpoint:

oxidising 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 oxidising properties 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

Sample tested:

other: test item / cellulose mixtures containing 10 to 90% test item in 10% increment weight

Parameter:

mean burning time

Remarks on result:

other: The negative result of the oxidising properties test on CeO2 supports the conclusion that the reaction mass of CeO2 and ZrO2 is not expected to exhibit oxidising properties.

Remarks:

CeO2 did not burn during the oxidising properties test

Description of key information

The constituents of the reaction mass of cerium dioxide and zirconium dioxide do not exhibit oxidising properties. Therefore, the reaction mass itself can also be considered not to have oxidising properties. This is supported by experience in day-to-day handling and use, which does not show any oxidising potential.

Key value for chemical safety assessment

Oxidising properties:

non oxidising

Additional information

For cerium dioxide, one GLP-compliant experimental study, scored as Klimisch 2, is available (Cerutti, 2005) and shows the substance does not have oxidising properties.

This study on cerium dioxide is used as supporting information in a read across analogue approach.

Justification for classification or non-classification

The constituents of the reaction mass of cerium dioxide and zirconium dioxide do not exhibit oxidising properties. Therefore, the reaction mass itself can also be considered not to have oxidising properties. This is supported by experience in day-to-day handling and use, which does not show any oxidising potential.