Potassium benzoate

Toxicity to terrestrial arthropods

Administrative data

Endpoint:

toxicity to terrestrial arthropods: short-term

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because direct and indirect exposure of the soil compartment is unlikely

other:

Justification for type of information:

The substance dissociates in water and the organic fraction will rapidly biodegrade.
Potassium is an essential element found in all plant cells and is abundant in soils.
Benzoates and benzoic acid are found in higher plant cells as building blocks for a with range of chemicals including hormones, cofactors, defence compounds and attractants for pollinators and seed dispersers, including many substances humans view as flavours and fragrances.
In view of the important of benzoates and their integrity for plant biochemistry, they are conisdered of low direct toxicity to higher plants. Plant eating organisms will be exposed to benzoates in normal diet.
Ref "A Familiar Ring to It: Biosynthesis of Plant Benzoic Acids", Joshua R. Widhalm, Natalia Dudareva, Molecular Plant, Volume 8, Issue 1, p83–97, 5 January 2015

Cross-reference

Reason / purpose for cross-reference:

data waiving: supporting information

Reference

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

weight of evidence

Study period:

28 day Ready Biodegradation

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

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

Justification for type of information:

Benzoate salts – justification for read-across. As with all salts, the significance for toxicity or environmental assessment is the presence of specific ions that will form when in solution or when in biological systems. In the case of metal salts of organic acids, the cation is generally critical to determine the solubility in biological or environmental media and if the key physico-chemical properties are equivalent, the potential for hazard and environmental fate will be equivalent; this is especially so for potassium and sodium salts that share similar solubility and dissociation characteristics.The cation is only critical in determining hazard if this is itself hazardous, but if the metal cations are present in the diet or are ‘essential’ elements for health, then there should be little to differentiated long-term hazards.
It is considered that potassium and sodium salts will behave in the same way under environmental conditions.

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method C.4-D (Determination of the "Ready" Biodegradability - Manometric Respirometry Test)

Version / remarks:

The aim of this ring-test programme was to examine the reliability of a method of assessing the biodegradability of chemical substances based on a UK adaptation of the Japanese MITI test so that it may be included in Annex V of the Directive 79/831/CEE.

Principles of method if other than guideline:

Test performed at 12 different laboratories as part of a method validation exercise. Sodium benzoate is usd as a reference substance for biodegradation testing

GLP compliance:

not specified

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, non-adapted

Details on inoculum:

Inoculum sludge grown on sewage

Duration of test (contact time):

28 d

Based on:

not specified

Remarks:

Range used

Parameter followed for biodegradation estimation:

O2 consumption

Reference substance:

not required

Remarks:

The research was to confirm sodium benzoate as a reference substance

Key result

Parameter:

% degradation (DOC removal)

Value:

64 - 97

Sampling time:

10 d

Parameter:

% degradation (DOC removal)

Value:

75 - 100

Sampling time:

28 d

Details on results:

As expected, sodium benzoate was readily degraded and values of biodegradation from all laboratories exceeded 60% after 14 days, t + 10 days

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

As expected, sodium benzoate was readily degraded and values of biodegradation from all laboratories exceeded 60% after 14 days, t + 10 days

Executive summary:

Test performed at 12 different laboratories as part of a method validation exercise. Sodium benzoate is used as a reference substance for biodegradation testing

A good level of biodegradation is noted with both benzoic acid and the sodium salt. 

Sodium benzoate is used as a reference substance for biodegradation testing and it is considered that potassium benzoate will behave in the same way.

Potassium and sodium benzoate dissociate under environmental conditions and the organic components will behave the same irrespective of the mono-valent metal ion associated with it.

Benzoate is rapidly biodegradable under aerobic conditions