2,2-dimethylpropane-1,3-diyl 2-ethylhexanoate

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

other information

Study period:

05 - 09 June 1995

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: Original report not available and documentation insufficient for assessment

Qualifier:

according to guideline

Guideline:

other: Brixham Environmental Laboratory Standard Operating Procedure BA128, version 9

GLP compliance:

not specified

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM- Common name: rainbow trout

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Nominal and measured concentrations:

Nominal: 180 mg/L

Reference substance (positive control):

not specified

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 180 mg/L

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Sublethal observations / clinical signs:

The tested nominal concentration of 180 mg/L, which showed no effect in this acute toxicity study, strongly exceeds the limit of water solubility (< 1 mg/L).

Validity criteria fulfilled:

not specified

Conclusions:

The tested nominal concentration of 180 mg/L, which showed no effect in this acute toxicity study, strongly exceeds the limit of water solubility (< 1 mg/L).96 h LC50 (mortality) > 180 mg/L (Oncorhynchus mykiss)Not meeting the requirements to classify for aquatic acute toxicity under Regulation (EC) No 1272/2008

Executive summary:

A study was conducted to assess the potential acute aquatic toxicity of 3-[(2-ethylhexanoyl)oxy]-2,2-dimethylpropyl 2-ethylheptanoate CAS: 28510-23-8 on Oncorhynchus mykiss. The study was performed in accordance to Brixham Environmental Laboratory Standard Operating Procedure BA128, version 9.

The results of the experiment concluded that nominal concentration of 180 mg/L, which showed no effect in this acute toxicity study, strongly exceeds the limit of water solubility (< 1 mg/L).

96 h LC50 (mortality) > 180 mg/L (Oncorhynchus mykiss).

Not meeting the requirements to classify for aquatic acute toxicity under Regulation (EC) No 1272/2008

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

11 Oct - 09 Nov 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Study was in accordance with OECD, EU, ISO test guidelines and conducted in a accredited GLP laboratory

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Qualifier:

according to guideline

Guideline:

ISO 7346-1 (Determination of the Acute Lethal Toxicity of Substances to a Freshwater Fish [Brachydanio rerio Hamilton-Buchanan (Teleostei, Cyprinidae)] - Part 1: Static Method)

Qualifier:

according to guideline

Guideline:

other: OECD series on testing and assessment number 23, 2000

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

- Sampling method: 4.5 mL were sampled at 0, 24, and 72 hours- Sample storage conditions before analysis: Samples were stored in a freezer until analysis. Additionally, reserve samples of 4.5 ml were taken from all test solutions for possible analysis. If not already used, these samples were stored in a freezer for a maximum of three months after delivery of the draft report, pending on the decision of the sponsor for additional analysis.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)- Method: Preparation of test solutions started with a loading rate of 100 mg/L applying two days of magnetic stirring to reach the maximum solubility of the test substance in the test medium. The resulting aqueous mixture was left to stabilize for approximately 3 hours where after a hazy Water Soluble Fraction (WSF) was siphoned off and used as the highest test concentration. The lower test concentrations for the range-finding test were prepared by subsequent dilutions of the WSF in test medium. These lower test solutions were all clear and colourless.

Test organisms (species):

Cyprinus carpio

Details on test organisms:

TEST ORGANISM- Common name: carp- Strain: F1 from a single parent-pair bred in UV-treated water- Source: Zodiac, proefacc, "De Haar Vissen", Wageningen University and Research Centre, The Netherlands- Length at study initiation (mean from ten fish):Range-finding test: 2.9 ± 0.3 cm Final test: 2.4 ± 0.1 cm- Weight at study initiation (mean):Range-finding test: 0.81 ± 0.19 g Final test: 0.40 ± 0.05 g- Feeding during test: noneACCLIMATION- Acclimation period: At least 12 days after delivery- Acclimation conditions (same as test or not): yes- Type and amount of food: pelleted fish food (Cyprico Crumble Excellent (300-500 µm), Coppens International bv, Helmond, The Netherlands) - Feeding frequency: daily- Health during acclimation (any mortality observed): none

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

180 mg/L as CaCO3

Test temperature:

21.1 - 22.3 °C

pH:

7.3 - 8.0

Dissolved oxygen:

5.4 - 9.2 mg O2/L

Nominal and measured concentrations:

100 mg/L (nominal)10 mg/L (mean measured)

Details on test conditions:

TEST SYSTEM- Test vessel:- Material, size, headspace, fill volume: 10 litres, all-glass, containing 8 litres of test solution for the test concentration and 9 litres of test solution for the control- Aeration: none- No. of organisms per vessel: 7- No. of vessels per concentration (replicates): 1- No. of vessels per control (replicates): 1- Biomass loading rate: 0.31 g fish/litre for the control and 0.35 g fish/litre for the test concentrationTEST MEDIUM / WATER PARAMETERS- Source/preparation of dilution water:Adjusted ISO medium, formulated using RO-water (tap-water purified by reverse osmosis; GEON Waterbehandeling, Berkel-Enschot, The Netherlands) with the following composition:CaCl2 x 2 H2O: 211.5 mg/LMgSO4 x 7 H2O: 88.8 mg/LNaHCO3: 46.7 mg/LKCl: 4.2 mg/LOTHER TEST CONDITIONS- Photoperiod: 16 hours light, 8 hours darkEFFECT PARAMETERS MEASURED (with observation intervals if applicable): Mortality and other effects at 2.75, 24, 48, 72 and 96 hours following the start of exposure. In addition, every afternoon from Day 0 and every morning from Day 1 to observe for any dead or severely distressed fish.TEST CONCENTRATIONSRange finding study:- Test concentrations: 0.10, 1.0, 10 and 100% of the WSF prepared at a loading rate of 100 mg/L- Results used to determine the conditions for the definitive study: No mortality or clinical effects were observed at any of the test concentrations during the test period. Based on these results samples taken from the highest test concentration were analysed. The initial concentration was 13 mg/L. This concentration decreased to 6.4 mg/L (51% of initial) after 24 hours of exposure and further to 1.4 mg/L (11% of initial) at the end of the test. The expected LC50 was above an average concentration of 4.5 mg/L.

Reference substance (positive control):

yes

Remarks:

pentachlorophenol

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 10 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

other: siphoned test solution

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

10 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

other: siphoned test solution

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities and mortality: No mortality or clinical effects were observed at both the control and the limit concentration during the test period.- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: From 24 hours onwards a floating layer was observed at the limit concentration, indicating that the actual test concentration was above the medium solubility.

Results with reference substance (positive control):

96h-LC50 = 0.25 mg/L (95% CL = 0.20 - 0.41 mg/L)

Sublethal observations / clinical signs:

Range-finding test:

No mortality or clinical effects were observed at any of the test concentrations during the test period. Based on these results samples taken from the highest test concentration were analysed. The initial concentration was 13 mg/L.This concentration decreased to 6.4 mg/L (51% of initial) after 24 hours of exposure and further to 1.4 mg/L (11% of initial) at the end of the test. The expected LC50 was above an average concentration of 4.5 mg/L.

Limit test:

Analysis of the sample taken from the limit concentration at the start of the test showed a measured concentration of 20 mg/L. This concentration decreased to 11 mg/L (56% of initial) after 24 hours of exposure and further to 7.0 mg/L (34% of initial) at the end of the test. Given this result, the effect parameters were based on the average exposure concentration that was calculated to be 10 mg/L.

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the study no mortality or clinical effects were observed at the control limit and the limit concentration. The following was determined: 96 h LC50 (mortality) > 10 mg/L 96 h NOEC (mortality) 10 mg/L

Executive summary:

96-Hour Acute Toxicity Study in Carp with 2,2-dimethylpropane-1,3-diyl 2-ethylhexanoate.

 

The study procedure described in this report was based on the OECD guideline No. 203, 1992. In addition, the procedures were designed to meet the test methods of the Commission Regulation (EC) No 440/2008, Part C.1, 2008, the ISO International Standard 7346-1: Static method, 1996 and the

OECD series on testing and assessment number 23, 2000.

 

The batch of 2,2-dimethylpropane-1,3-diyl 2-ethylhexanoate tested was a clear colourless liquid with a purity of >98% (based on GC-FID area-%) and not completely soluble in test medium at the loading rates initially prepared.

 

A limit test was performed based on the results of a preceding range-finding test. Preparation of the test solution started with a loading rate of 100 mg/l applying two days of magnetic stirring to reach the maximum solubility of the test substance in the test medium. The resulting aqueous mixture was left to stabilize for approximately 3 hours where after a hazy Water Soluble Fraction (WSF) was siphoned off and used for testing.

 

Analysis of the sample taken from the limit concentration at the start of the test showed a measured concentration of 20 mg/l. This concentration decreased to 11 mg/l (56% of initial) after 24 hours of exposure and further to 7.0 mg/l (34% of initial) at the end of the test. Given this result, the effect parameters were based on the average exposure concentration that was calculated to be 10 mg/l.

 

From 24 hours onwards a floating layer was observed at the limit concentration, indicating that the actual test concentration was above the medium solubility.

 

The study met the acceptability criteria prescribed by the protocol and was considered valid.

2,2-dimethylpropane-1,3-diyl 2-ethylhexanoate induced no visible effects in carp at an average exposure concentration of 10 mg/l (NOEC).

 

The 96h-LC50 was >10 mg/l.

Description of key information

No toxic effects up to the limit of water solubility (< 0.01 mg/L) for Danio rerio (OECD 203) 

Additional information

One study investigating the short-term toxicity of 2,2-dimethylpropane-1,3-diyl 2-ethylhexanoate (CAS No. 28510-23-8) to freshwater fish is available. The GLP study was conducted under static conditions according to OECD guideline 203 using Danio rerio as test organism (Bouwman, 2012a). A limit test was performed based on the results of a preceding range-finding test. Preparation of the test solution started with a loading rate of 100 mg/l applying two days of magnetic stirring to reach the maximum solubility of the test substance in the test medium. The resulting aqueous mixture was left to stabilize for approximately 3 hours whereupon a hazy water soluble fraction was siphoned off and used for testing. 

Analysis of the sample taken from the limit concentration at the start of the test showed a measured concentration of 20 mg/l. This concentration decreased to 11 mg/l (56% of initial) after 24 hours of exposure and further to 7.0 mg/l (34% of initial) at the end of the test. Given this result, the effect parameters were based on the average exposure concentration that was calculated to be 10 mg/l. From 24 hours onwards a floating layer was observed at the limit concentration, indicating that the actual test concentration was above the medium solubility. No mortality was observed in the treatment and the control throughout the test period of 96 h. Hence, a 96 h-LC50 is determined to be > 100 mg/L based on the nominal test concentration (> 10 mg/L, measured), which is well above the limit of water solubility (< 0.01 mg/L in aqua dest) for this substance.