Bis(2-ethylhexyl) adipate

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

24 - 27 Oct 1989

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

other: DIN 38412, part 9

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: A 500 mg/L stock solution was preparted using 200 mg/L Cremophor as dispersant. After stirring of 17h the test solution was still an emulsion. This emulsion was tested.
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): Cremophor
- Concentration of vehicle in test medium (stock solution and final test solution(s) including control(s)): 200 mg/L
- Evidence of undissolved material (e.g. precipitate, surface film, etc): Test solutions were emulsions.

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISMS
- Strain: SAG 86.81
- Method of cultivation: temperature: 20°C, stock culture 10000 cells/mL, cultivation in 250 ml Erlenmeyer flasks, test volume 100 mL

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test temperature:

20 °C

pH:

not specified

Nominal and measured concentrations:

Nominal: 7.812, 15.625, 31.25, 62.5, 125, 250 and 500 mg/L

Details on test conditions:

TEST SYSTEM
- Fill volume: 10 mL
- Initial cells density: 10000 cells/mL
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- No. of vessels per vehicle control (replicates): 4

GROWTH MEDIUM
- Standard medium used: yes (OECD medium)

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: not specified
- Culture medium different from test medium: no

EFFECT PARAMETERS MEASURED: Biomass was recorded after 0, 24, 48 and 72h exposure time.
- Determination of cell concentrations: fluorimeter

Reference substance (positive control):

no

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 500 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Duration:

72 h

Dose descriptor:

EC20

Effect conc.:

398.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Duration:

72 h

Dose descriptor:

EC100

Effect conc.:

> 500 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Details on results:

- Exponential growth in the control (for algal test): yes
- Observation of abnormalities (for algal test): no

Validity criteria fulfilled:

yes

Conclusions:

A 72h acute toxicity test with Scenedesmus subspicatus revealed that DEHA is not acutely harmful to freshwater algae up to the saturation limit in water.

Executive summary:

The study was performed according to DIN guideline 38412, part 9 using Scenedesmus subspicatus as test organism. A 500 mg/L stock solution was preparted using 200 mg/L Cremophor as dispersant. After stirring of 17h the test solution was still an emulsion. This emulsion was tested. Nominal test concentrations between 7.8 and 500 mg/L were tested. The 72h-EC50 value is determined to be > 500 mg/L. An 72h-EC20 value is determined to be 398.6 mg/L. Since the effect concentration is greater than the solubility of DEHA in the test medium, it can be concluded that DEHA is not harmful to freshwater algae up to the saturation limit in water.

Reference 2

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well documented peer-reviewed publication, which meets basic scientific principles

Qualifier:

according to guideline

Guideline:

other: EPA-600/9-78-018

GLP compliance:

no

Analytical monitoring:

not specified

Vehicle:

no

Test organisms (species):

Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

> 78 mg/L

Basis for effect:

growth rate

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

> 0.78 mg/L

Basis for effect:

growth rate

Validity criteria fulfilled:

not specified

Conclusions:

A 96h acute toxicity test with Selenastrum capricornutum revealed that DEHA is not acutely harmful to freshwater algae up to the saturation limit in water.

Reference 3

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: Guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

Version / remarks:

Cited as Directive 92/69/EEC, C.3

GLP compliance:

yes

Analytical monitoring:

yes

Vehicle:

no

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 1.4 mg/L

Nominal / measured:

not specified

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

> 1.4 mg/L

Nominal / measured:

not specified

Conc. based on:

test mat.

Basis for effect:

growth rate

Validity criteria fulfilled:

not specified

Conclusions:

The concentration of 1.4 mg/L is well above water solubility. It can be concluded that the test substance is not acutely harmful to algae within its water solubility.

Description of key information

No toxicity is observed within the limit of water solubility.

Additional information

Three studies investigating the toxicity of DEHA to feshwater algae are available. The key study was performed according to DIN guideline 38412, part 9 using Scenedesmus subspicatus as test organism (BASF 1989). A 500 mg/L stock solution was preparted using 200 mg/L Cremophor RH40 as dispersant. After stirring of 17h the test solution was still an emulsion. This emulsion was tested. Nominal test concentrations between 7.8 and 500 mg/L were tested. The 72h-EC50 value is determined to be > 500 mg/L. An 72h-EC20 value is determined to be 398.6 mg/L. Since the effect concentration is greater than the solubility of DEHA in the test medium, it can be concluded that DEHA is not harmful to freshwater algae up to the saturation limit in water.

Result and conclusion is confirmed by two supporting studies, which assessed the acute toxicity of DEHA to Selenastrum capricornutum (Felder et al. 1989) and Scenedesmus subspicatus (Hüls 1996), respectively.