Chromate(2-), [2,4-dihydro-4-[(2-hydroxy-4-nitrophenyl)azo]-5-methyl-2-phenyl-3H-pyrazol-3-onato(2-)][3-[(4,5-dihydro-3-methyl-5-oxo-1-phenyl-1H-pyrazol-4-yl)azo]-2-hydroxy-5-nitrobenzenesulfonato(3-)]-, disodium

Explosiveness

Link to relevant study record(s)

Reference

Endpoint:

explosiveness, other

Type of information:

other: Expert statement

Adequacy of study:

key study

Study period:

2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Qualifier:

according to guideline

Guideline:

other: CLP, Annex I, Part 2, paragraphs 2.1.4.2 and 2.1.4.3

Qualifier:

according to guideline

Guideline:

other: Appendix 6 of the UN Recommendations on the Transport of Dangerous Goods, Manual of Tests and Criteria

Qualifier:

according to guideline

Guideline:

other: Technical Guidance Document on the Information Requirements for REACH, Part 2 EWG 1-7, REACH Implementation Project (RIP) 3.3 Phase 2, chapter 7.1.11.3

GLP compliance:

no

Key result

Parameter:

other: The calculated chemical oxygen balance is above the trigger value of -200 and the determination of the exothermic decomposition energy demonstrated an energy release above the critical value of 500 J/g while the onset of energy release is below 500 °C.

Remarks on result:

other: Expert assessment

Remarks:

A screening evaluation was performed

Screening evaluation:

Analysis of the molecular structure of Acid Red 315 revealed, that two nitro-groups are present in the molecule representing alert structures regarding explosive properties.

Calculation of the oxygen balance according to the above mentioned formula is -126.82 and therefore higher than the trigger value of -200.

Determination of the exothermic decomposition energy:

The curve displayed one exothermic peak between 220 and >350 °C with an energy release of 548.22 J/g. This peak is considered to represent substance decomposition energy. As a result, energy release is above a critical trigger level of 500 J/g but the onset of energy release is below 500 °C.

Data availability for related sales products:

For one of the related sales products containing approximately 75 % of the crude dye (Lanacron Red S-G) additional data are available. For this product the following tests have been conducted:

-       Combustibility test according to VDI 2263, SAV: 006a

-       Decomposition test (Lütolf dynamic) according to VDI 2263, SAV: 010

-       Spontaneous decomposition (deflagration) according to VDI 2263, SAV: 029

-       Decomposition Gas according to VDI 2263, SAV: 010

-       Decomposition test dynamic (Grewer air) according to VDI 2263, SAV: 008

-       Self-Ignition-Temperature (Wire Basket isoperibolic) according to VDI 2263, SAV: 024

-       Dust explosibility in a modified Hartmann apparatus according to VDI 2263, SAV: 013

-       Minimum ignition energy (MIE) MIKE 3 according to EN 13821, ASTM E2019-03, SAV: 001

-       DSC-Test dynamic according to ASTM E537-02, DIN 51005, SAV: 421

As a result of these tests the product is considered to be positive for spontaneous decomposition (GKD class 1) and positive regarding dust explosibility. The test on composition gas was evaluated negative. The test on combustibility either at room temperature or at 100 °C resulted in a combustibility index of 4(Persistent glowing without the emission of sparks or slow decomposition without a flame). A DSC curve recorded up to 400 °C demonstrated an energy release of dH = -846 J/g between 153 °C and 397 °C (peak: 306 °C).

Interpretation of results:

other: further data required

Conclusions:

No conclusion on the explosive properties of the substance could be reached without further data, therefore it is proposed to further investigate the substance in a Koenen-Test according to EU Method A.14.

Executive summary:

Analysis of the chemical structure reveals two nitro groups present in the molecule representing alert structures for explosive properties. The calculated chemical oxygen balance is above the trigger value of -200 and the determination of the exothermic decomposition energy demonstrated an energy release above the critical value of 500 J/g while the onset of energy release is below 500 °C. Additional data generated for a product containing about 75 % of the pure dye demonstrated to be positive in a test on spontaneous decomposition with a gas quantitiy of 60 L/kg at 350 °C while the released gases are not observed to be flammable. As a conclusion, the explosive properties of the substance cannot be fully evaluated without further data, therefore it is proposed to further investigate the substance in a Koenen-Testaccording to EU Method A.14.

Description of key information

An analysis of the chemical structure reveals two nitro groups present in the molecule representing alert structures for explosive properties. The calculated chemical oxygen balance is above the trigger value of -200 and the determination of the exothermic decomposition energy demonstrated an energy release above the critical value of 500 J/g while the onset of energy release is below 500 °C. Additional data generated for a product containing about 75 % of the pure dye demonstrated to be positive in a test on spontaneous decomposition with a gas quantity of 60 L/kg at 350 °C while the released gases are not observed to be flammable. As a conclusion, the explosive properties of the substance cannot be finally evaluated without further data, therefore it is proposed to further investigate the substance in a Koenen-Test according to EU Method A.14.

Key value for chemical safety assessment

Explosiveness:

non explosive