2,2-dimethylpropane-1,3-diyl dibenzoate

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study without restriction

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

no

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

SAMPLING SCHEDULE:
- Control: at 0 h (2014-09-01, 2014-09-02, 2014-09-03, 2014-09-04) and 24 h (2014-09-02, 2014-09-03, 2014-09-04 and 2014-09-05) according to the semi-static conditions
- Test concentrations : 100 mg/L in the freshly prepared media (on 2014-09-01, 2014-09-02, 2014-09-03 and 2014-09-04) and in the media after 24 h of exposure (on 2014-09-02, 2014-09-03, 2014-09-04 and 2014-09-05) according to the semi-static conditions

Vehicle:

no

Details on test solutions:

Pre-TREATMENT OF TEST ITEM AND PREPARATION OF TEST ITEM CONCENTRATIONS:
- Direct weighings were prepared daily to produce the test item concentration.
- To achieve this 500 mg of the test item were added daily to 5 litres of dilution water, treated for 1 h in an ultrasonic bath and stirred for 3 h on a magnetic stirrer.
- Undissolved particles of the test item were removed by filtration using a folded filter with a pore size of 7-12 μm.
- The pH was adjusted to pH 7.0 to reduce hydrolytic processes.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST SPECIES:
- Name: Zebra fish (Danio rerio)
- Source: West Aquarium GmbH (Germany)
- Date supplied: 2014-06-12
- Acclimatisation: Stock held since 2014-06-12 and acclimatised to the test conditions since then

MAINTANANCE:
- Temperature: 20-24°C
- Dissolved oxygen: > 5 mg/L
- Feeding : Commercial fish food, daily; feeding discontinued 24 h prior to test start
- Holding water: dechlorinated tap water: hardness 15° dH, acidity: 0.1 +/- 0.02 mmol/l; Ca/Mg: 4:1; pH: 6.3-6.8; oxygen: >= 90 % of saturation
- Mortalities during acclimatisation period: < 5 %
- Medication: none
- Mean standard length (n = 14): 3.58 cm (S.D. = 0.22 cm)

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

14.0 °dH (250 mg/L CaCO3)

Test temperature:

21.5 to 22.1 °C

pH:

adjusted to pH 7 after day 1, 2 and 3

Dissolved oxygen:

7.8 - 9.1 (mg/L)

Salinity:

n.a.

Nominal and measured concentrations:

Effective concentrations ranged from 0.33 % to 0.74 % of nominal values in the freshly medium and from 0.08 % to 0.36 % of nominal values in the medium after 24 hours of exposure.

Details on test conditions:

EXPOSURE CONDITIONS:
- Test vessels: glass aquaria holding 5 L of test media covered by glass plates
- Experimental design: 1 test concentration plus 1 control; 7 fish per test concentration; no feeding during the exposure period
- Method of initiation: fish were placed in prepared media
- Loading: 0.95 g body weight (wet weight) per litre
- Photoperiod: 16 h light: 8 h dark
- Aeration: gentle aeration via narrow glass tubes
- Test item concentration/s: 100 mg/L
- Method of administration: direct weighing
- Medium renewal: daily
- Criteria of effects: The criterion of death was the absence of response to physical stimulation. In addition to observations on mortality at 2, 24, 48, 72 and 96 hours, type and incidence of sub-lethal effects compared with control fish were observed.

Reference substance (positive control):

not required

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 0.28 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

> 0.158 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

All results are expressed in terms of geometric mean measured concentrations.

Validity criteria fulfilled:

yes

Remarks:

(mortality in the controls < 10% by the end of the test; dissolved oxygen concentration above 60% of the air-saturation value throughout the exposure period; pH did not vary by more than 1 unit)

Conclusions:

The toxicity of 2,2-dimethylpropane-1,3-diyl dibenzoate to fish was determined at LC50 of higher than 0.28 mg/L after 96 hours. No toxic effects against fish were observed at the limit of water solubility under exposure conditions. All results are expressed in terms of geometric mean measured concentrations. Effective concentrations ranged from 0.33 % to 0.74 % of nominal values in the freshly medium and from 0.08% to 0.36 % of nominal values in the medium after 24 hours of exposure.

Executive summary:

A study was performed to assess the acute toxicity of 2,2-dimethylpropan-1,3-diyl dibenzoate to Danio rerio under semi-static conditions.

The study was conducted in accordance with Council Regulation (EC) No 440/2008, Method C.1 'Acute toxicity for Fish' (2008) which is in most parts equivalent to the OECD Guideline for Testing of Chemicals No. 203 'Fish, Acute Toxicity Test' (1992).

A group of seven fish of the recommended size was exposed to a limit test concentration of nominally 100 mg/L of 2,2-dimethylpropan-1,3-diyl dibenzoate dissolved in dilution water. Auxiliaries used to prepare the test media were an ultrasonic bath, a magnetic stirrer and folded filters. Observations were made on the number of dead fish and the incidence of sub-lethal effects after 2, 24, 48, 72 and 96 hours of exposure.

No toxic effects of 2,2-dimethylpropane-1,3-diyl dibenzoate against fish were observed at the limit of water solubility under exposure conditions. This toxicity study is classified as acceptable and satisfies the guideline requirements for the acute Fish study.

Description of key information

The toxicity of 2,2-dimethylpropane-1,3-diyl dibenzoate to fish was determined at LC50 of higher than 0.28 mg/L after 96 hours. No toxic effects against fish were observed at the limit of water solubility under exposure conditions. All results are expressed in terms of geometric mean measured concentrations. Effective concentrations ranged from 0.33 % to 0.74 % of nominal values in the freshly medium and from 0.08% to 0.36 % of nominal values in the medium after 24 hours of exposure.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

0.28 mg/L

Additional information

Should read: ">0.28 mg/L"