Tris(2-ethylhexyl) benzene-1,2,4-tricarboxylate

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:

1998

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 0, 17.1, 30.9, 55.6, 100 and 180 mg/L
- Sampling method: No data
- Sample storage conditions before analysis: No data

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Tris(2-ethylhexyl)benzene-1,2,4-tricarboxylate was diluted to 1800mg/L (with solubilizer HCO-40 1000mg/L) with diluting water (Elendt M4) before use
- Eluate: dilution water
- Differential loading: No data
- Controls: yes - dilution water and test medium with dispersant
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): solubilizer HCO-40 1000mg/L
- Concentration of vehicle in test medium (stock solution and final test solution): 100 mg/L
- Evidence of undissolved material (e.g. precipitate, surface film, etc): Tris(2-ethylhexyl)benzene-1,2,4-tricarboxylate became cloudy in high concentration, but no precipitation was seen

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Source:NIES Japan
- Age at study initiation (mean and range, SD): within 24h old
- Feeding during test: No

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48

Post exposure observation period:

No

Hardness:

228 mg/l as CaCO3

Test temperature:

19.9-20.2 °C (mean temperature 20°C).

pH:

7.3-7.8

Dissolved oxygen:

8.0-8.6 mg/l

Salinity:

N/A fresh water

Nominal and measured concentrations:

Nominal Concentrations: 0, 17.1, 30.9, 55.6, 100 and 180 mg/L
Mean measured concentrations: 0, 15.8, 28.9, 52.5, 97.3, 177.5 (See Results table below)

Details on test conditions:

TEST SYSTEM
- Test vessel: glass beaker
- Material, size, headspace, fill volume: 100 ml
- Aeration:
- Type of flow-through (e.g. peristaltic or proportional diluter):
- Renewal rate of test solution (frequency/flow rate): N/A static
- No. of organisms per vessel: 20
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- No. of vessels per vehicle control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Elendt M4(OECD guideline No.211 Annex 2)
- Intervals of water quality measurement: 48h

OTHER TEST CONDITIONS
- Adjustment of pH: No
- Photoperiod: 16h light / 8h dark
- Light intensity: room light

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : mortality

TEST CONCENTRATIONS
- Spacing factor for test concentrations: ca 1.8
- Justification for using less concentrations than requested by guideline: N/A
- Range finding study
- Test concentrations: up to at least 1000 mg/l in immobilisation test
- Results used to determine the conditions for the definitive study:48h-EC50 for parent Daphnia (Acute immobilization test) was >1000mg/L. Dispersant control was also tested

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 180 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 180 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

180 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

> 180 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: No abnormal responses observed during test period
- Other biological observations: No
- Mortality of control: No mortality observed during test period
- Other adverse effects control: No
- Abnormal responses: No abnormal responses observed during test period
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: The Tris(2-ethylhexyl)benzene-1,2,4-tricarboxylate containing media became cloudy in high concentration, but no precipitation was seen
- Effect concentrations exceeding solubility of substance in test medium: No

Results with reference substance (positive control):

- Results with reference substance valid? yes
- EC50/LC50: 0.87 mg/L (48h)

Reported statistics and error estimates:

Not applied for EC50 - No concentration related effects observed
Method of calculating mean measured concentrations: Geometric mean

Measured Concentrations of test chemicals during a 48h exposure period

Nominal Concentration      Measured concentration (mg/L)   Percent of nominal concentration (mg/L)

                                             0hr       48hr      Mean                    0hr      48hr

           Control                               < 1.0      < 1.0           -                       -            -

   Disp.Cont.                          < 1.0      < 1.0           -                       -            -

   17.1                                      16.3       15.4        15.8                   95.3      90.1

    30.9                                      29.4       28.5        28.9                   95.1      92.2

    55.6                                      53.0       52.1        52.5                   95.3      93.7

   100.0                                     98.4       96.3        97.3                   98.4      96.3

   180.0                                   179.2    175.8      177.5                    99.6      97.7

                   Mortality or immobility of Daphnia magna exposed to the test chemicals

                       Nominal concentration (mg/L)     Cumulative number of dead or immobilized Daphnia

                                                                                      (Percent Mortality or Immobility)

                                                                                      24 hour                 48 hour

                                    Control                                       0(0)                        0(0)

                          Dispersant Control                              0(0)                         1(5)

                                       17.1                                          0(0)                         1(5)

                                       30.9                                          0(0)                         0(0)

                                       55.6                                          0(0)                         0(0)

                                     100.0                                          0(0)                         0(0)

                                     180.0                                          0(0)                         0(0)

 

·               

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of this test the EC50 (48h) > 180mg/L and NOEC (48h) > 180mg/L for Daphnia magna Tris(2-ethylhexyl)benzene-1,2,4-tricarboxylateor

Executive summary:

Acute immobilisation in Daphnia has been investigated in a 48 hour test according to OECD test methods. Dissolution/dispersion agents were used to increase concentration of the substance in the test medium. The EC50 (48h) was determined to be >180 mg/L and the NOEC was 180 mg/L, the highest concentration investigated.

Description of key information

Short-term toxicity to Daphnia: EC50 - >180 mg/L; NOEC - 180 mg/L

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

LC50

Effect concentration:

180 mg/L

Additional information

Acute immobilisation in Daphnia has been investigated in a 48 hour test according to OECD test methods. Dissolution/dispersion agents were used to increase concentration of the substance in the test medium. The EC50 (48h) was determined to be >180 mg/L and the NOEC was 180 mg/L, the highest concentration investigated.