Reaction mass of 2,2,4-trimethylhexane-1,6-diol and 2,4,4-trimethylhexane-1,6-diol

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2001-05-08 to 2001-05-18

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

(1984)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

(1992)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

Analysis at beginning and end of test

Details on test solutions:

- Concentration: 0.52 g/l stirred in synthetic fresh water (no NaHCO3) for 24 hours, no vehicle or solvent; analytical concentration 501 mg/l

Test organisms (species):

Daphnia magna

Details on test organisms:

- Strain: Daphnia magna Straus, clone 5
- Source/supplier: Infracor GmbH (inhouse)
- Breeding method: In 1 l beakers with M4 medium (Elendt, 1990), water renewal each 2-3 days, isolation of offspring for further breeding each ca. 4 weeks
- Age: < 24 hours
- Feeding: Scenedesmus subspicatus, daily as much as consumed
- Pretreatment: Separation from adults 24 h prior to testing

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

14 degree dH = 250 mg CaCO3/l (dilution water)

Test temperature:

20 +/- 1 degree C

pH:

7.8 - 8.6

Dissolved oxygen:

7.4 - 8.1 mg/l

Nominal and measured concentrations:

Nominal: 9.4, 16, 27, 52, 83, 135, 239, 416 mg/l
Measured: 9.9, 15.3, 26.1, 50.5, 83.4, 137, 239, 410 mg/l (0 hours); 9.6, 14.9, 25.3, 49.5, 81.6, 125, 253, 401 mg/l (48 hours)

Details on test conditions:

DILUTION WATER
- Source: Synthetic: CaCl2 x 2 H2O: 294 mg/l MgSO4 x 7 H2O: 114 mg/l NaHCO3: 65 mg/l KCl: 6 mg/l - Ca/Mg ratio: 4:1 - Na/K ratio: 10:1
- Aeration: none
- Exposure vessel type: Round-bottom test tubes with 10 ml
- Number of replicates, individuals per replicate: 4 replicates with 5 individuals each
- Adjustment of pH: no
- Photoperiod: dark
- Feeding during test: none
- Control group: 2 reference substance controls (1.0 and 2.0 mg/l), one blank


TEST PARAMETER: immobilisation

Reference substance (positive control):

yes

Remarks:

potassium dichromate, CAS RN 7778-50-9

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

27 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

80 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

416 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Results with reference substance (positive control):

Concentrations: 1.0 mg/l / 2.0 mg/l
- Results: 40 % immobile / 100 % immobile (24 hours)

- Effect data (Immobilisation): No. of immobile daphnia
  control:    0 (24 h) /   0 (48 h)
   9.4 mg/l:  0 (24 h) /   0 (48 h) 
  16   mg/l:  0 (24 h) /   0 (48 h)
  27   mg/l:  0 (24 h) /   0 (48 h) (21 individuals)
  52   mg/l:  3 (24 h) /   5 (48 h) (21 individuals)
  83   mg/l:  9 (24 h) /  10 (48 h) 
  135  mg/l: 16 (24 h) /  18 (48 h)
  239  mg/l: 16 (24 h) /  20 (48 h) (21 individuals)
  416  mg/l: 20 (24 h) /  20 (48 h)
  EC50 (24 h) = 101 mg/l
  EC50, 95 % confidence interval: 79 - 130 mg/l (24 h)
  EC50, 95 % confidence interval: 64 -  99 mg/l (48 h)

Validity criteria fulfilled:

yes

Conclusions:

The EC50 (48 h) was determined as 80 mg/L indicating that the test subsance may be harmful to aquatic invertebrates.

Executive summary:

The test substance was tested in an Acute Daphnia Toxicity Test according to the OECD Guideline for the Testing of Chemicals No. 202 (April 2004) using Daphnia magna (Straus) as test organism. The experiment was carried out as a static test, i.e. the test substance preparations were not exchanged for the whole exposure period of 48 hours. The test was performed with test substance preparations of nominal 9.4, 16, 27, 52, 83, 135, 239 and 416 mg/l test substance/L M4 medium. The EC₅₀value after 48 hours of exposure was 80 mg/L based on nominal concentrations.

Description of key information

The test substance was tested in an Acute Daphnia Toxicity Test according to the OECD Guideline for the Testing of Chemicals No. 202 (April 2004) using Daphnia magna(Straus) as test organism. The experiment was carried out as a static test, i.e. the test substance preparations were not exchanged for the whole exposure period of 48 hours. The test was performed with test substance preparations of nominal 9.4, 16, 27, 52, 83, 135, 239 and 416 mg/ltest substance/L M4 medium. The EC₅₀value after 48 hours of exposure was 80 mg/L based on nominal concentrations.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

80 mg/L