Butanedioic acid, 2-hydroxy-, 1,4-bis[5,7,7-trimethyl-2-(1,3,3-trimethylbutyl)octyl] ester

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2015-08-06 to 2015-10-21

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP and appropriate guidelines

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.1010 (Aquatic Invertebrate Acute Toxicity Test, Freshwater Daphnids)

Deviations:

no

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: JMAFF (12-Nousan-No.8147,2-7-2-1,24 November, 2000)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

1,4-bis[2-(4,4-dimethylpentan-2-yl)-5,7,7-trimethyloctyl] 2-hydroxybutanedioate

EC Number:

807-422-1

Cas Number:

66918-01-2

Molecular formula:

C40H78O5

IUPAC Name:

1,4-bis[2-(4,4-dimethylpentan-2-yl)-5,7,7-trimethyloctyl] 2-hydroxybutanedioate

Sampling and analysis

Analytical monitoring:

not specified

Test solutions

Vehicle:

yes

Details on test solutions:

Reconstituted water (ISO medium, according to OECD 202) was used as dilution water for both the range-finding and definitive tests. The same composition of reconstituted water was used for the tests and for breeding the test animals.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

Breeding The Daphnia are bred in Ecotoxicological TEST Laboratory.
The health of the stock animals is continuously monitored by visual daily checking. Abnormal behavior or significant decrease of population is recorded.
Justification of strain: Daphnia magna is the standard species of the acute immobilisation test.
Number of animals: There were 20 animals in test group and control group respectively, divided into 4 replicates (5 animals / replicate)
Age of the animals: They were less than 24 h old at the beginning of the test
Acclimatization: There was no acclimatization because the water used was similar to the culture water.

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Post exposure observation period:

The immobility or mortality of the Daphnia was determined by visual observation 24 and 48 hours after the start of the test. Those animals not able to swim within 15 seconds after gentle agitation of the test beaker are considered to be immobile.
The number of immobilised animals and the percentage of immobility were determined at 24 and 48 hours.
The water temperature, oxygen concentrations and pH of the control and the test solution were measured at the beginning and at the end of the renewal periods.

Test conditions

Hardness:

The reconstituted water (ISO medium) had a total hardness of 246 mg/L (as CaCO3).

Test temperature:

Start of test, renewal period and end of test: 20.2 – 20.6°C.
The additionally measured temperature in the climate chamber was between 19.7 and 20.7°C.

pH:

The pH of the test solution was not adjusted and not varied by more than 1.5 units in any one test.
Start of test, renewal period and end of test: 7.32 – 7.89.

Dissolved oxygen:

Start of test, renewal period and end of test: 8.2 – 8.4 mg/L.

Salinity:

no further details

Nominal and measured concentrations:

Because the test item is very poorly soluble in water, a test solution was prepared according to OECD method No. 23.
Nominal concentration: 100 mg/L and non-dissolved test material was removed to obtained a 100% saturated solution.

Details on test conditions:

According to guidelines

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 other: % saturated solution

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks:

and percentage of immobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 other: % saturation

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks:

and percentage of immobility

Effect concentrations 3

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

100 other: % saturated solution

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks:

and percentage of immobility

Effect concentrations 4

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

> 100 other: % saturated solution

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks:

and percentage of immobility

Effect concentrations 5

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

> 100 other: % saturated solution

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks:

and percentage of immobility

Reported statistics and error estimates:

No statistical analysis was performed because of the lack of toxic effects. The EC50, NOEC, LOEC and EC100 values were determined directly from the raw data.

Any other information on results incl. tables

Number and percentage of immobilised animals

		Number of immobilised animals
Test group	Number of treated animals	24 hours		48 hours
		number	percent	number	percent
Control	20	0	0	0	0
100% saturated solution	20	0	0	0	0

In addition to immobility, no abnormal behavior or appearance of test animals was detected.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Acute toxicity of Bis[2-(4,4-dimethylpentan-2-yl)-5,7,7-trimethyloctyl] malate was assessed with Acute immobilisation test on Daphnia magna, over an exposure period of 48 hours in a semi-static system.
All validity criteria were met during this study.

Under the conditions of this Daphnia magna acute immobilisation study the observed endpoints for the effect of Bis[2-(4,4-dimethylpentan-2-yl)-5,7,7-trimethyloctyl] malate were the followings:

The 24h and 48h EC50 value: > 100 % saturated solution (nominal)
The 48h (NOEC): 100 % saturated solution (nominal)
The 48h (LOEC): > 100 % saturated solution (nominal)
The 48h EC100 value: > 100 % saturated solution (nominal)
Based on the results of this study, the Bis[2-(4,4-dimethylpentan-2-yl)-5,7,7-trimethyloctyl] malate had no toxic effect at saturation; the EC50 results and the LOEC are higher than the solubility level of the test item in the test medium.

Executive summary:

Acute toxicity of Bis[2-(4,4-dimethylpentan-2-yl)-5,7,7-trimethyloctyl] malate on Daphnia magna was assessed in an Acute immobilisation test, over an exposure period of 48 hours in a semi-static test system. Toxic effects were not observed during the preliminary concentration range-finding test therefore a limit test was performed in the main experiment using only one test concentration at the limit of solubility of the test item in the test medium (100 % saturated solution) and one control group.

The experiment was carried out without analytical support based on agreement with the Sponsor.

Twenty animals, divided into four groups (glass beaker) of five animals each were used at the test concentration and for the control.

No statistical analysis was performed because of the lack of toxic effects. The EC₅₀, NOEC, LOEC and EC₁₀₀values were determined directly from the raw data. All validity criteria were met during this study.

Under the conditions of this Daphnia magna acute immobilisation study the observed endpoints for the effect of Bis[2-(4,4-dimethylpentan-2-yl)-5,7,7-trimethyloctyl] malate were the followings:

The 24h and 48h EC₅₀value:    >100 % saturated solution (nominal)

The 48h NOEC:                            100 % saturated solution (nominal)

The 48h LOEC:                          >100 % saturated solution (nominal)

The 48h EC₁₀₀value:                 >100 % saturated solution (nominal)

Based on the results of this study, the test item Bis[2-(4,4-dimethylpentan-2-yl)-5,7,7-trimethyloctyl] malate had no toxic effect at saturation; the EC₅₀ results and the LOEC are higher than the solubility level of the test item in the test medium.