Chloroacetic acid

Explosiveness

Link to relevant study record(s)

Reference

Endpoint:

explosiveness, other

Study period:

11 May 2009 - 4 November 2009

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because there are no chemical groups present in the molecule which are associated with explosive properties

Qualifier:

according to guideline

Guideline:

EU Method A.14 (Explosive properties)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

The tendency of a compound to undergo violent or explosive decomposition is an important safety consideration. In general, the oxygen balance and various structural parameters (bond groupings) are factors associated with explosive properties.

 

The molecular structure of the test substance does not contain any chemically instable or highly energetic groups that might lead to an explosion. The impurities, present for < 0.3% in the test substance, were not taken into account but it is not to be expected that these have any influence.

 

The oxygen balance of a compound is the difference between the oxygen content of the compound and that required to fully oxidize the carbon, hydrogen and other oxidisable elements to carbon dioxide, water, etc. Nitrogen is not considered oxidisable and is usually liberated as the gaseous element during explosive decomposition.

 

The oxygen balance is calculated for the chemical reaction:

CcHhOo + [c + (h/4) – (o/2)] O₂→c CO₂+ (h/2) H₂O

where c, h and o are the amounts of carbon, hydrogen and oxygen atoms respectively.

Oxygen balance (%) = -1600 x [2 x c + (h/2) – o] / molecular weight

 

If there is a deficiency of oxygen, the balance is negative, while an excess of oxygen gives a positive balance. Compounds with a positive balance can act as oxidants and are often explosive in nature. However, there are known explosives with an oxygen balance of - 64%. Compounds with an oxygen balance which is more negative than -200% are not considered to pose an explosive risk.

 

Using C₂H₃O₂Cl as molecular formula and 94.497 g/mol as molecular weight, the oxygen balance for the test substance was calculated to be –59 %. This is > -200% and therefore within the region where there may be a potential for explodability. However, there are no plosophores (bond groupings known to give explosive properties) or auxoploses (explosive enhancing groups) present in the structure. The relatively high oxygen balance is considered to be due to the size of the molecule in combination with the presence of a chlorine atom and a carboxylic acid group in the molecule. Overall consideration of the properties does not suggest a risk of explodability.

Interpretation of results:

Division 1.4 (substances, mixtures and articles which present no significant hazard) based on GHS criteria

Remarks:

Migrated information

Conclusions:

In conclusion, Monochloroacetic acid (MCAA) is not explosive.

Description of key information

Based on structure, Monochloroacetic acid (MCAA) is not explosive.

Key value for chemical safety assessment

Explosiveness:

non explosive