Dibutyl 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:

other information

Study period:

1988

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: Only secondary literature. Original report not available.

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Test type:

static

Water media type:

freshwater

Total exposure duration:

72 h

Nominal and measured concentrations:

not stated

Reference substance (positive control):

not specified

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

2.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Reference 2

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02 Feb - 05 Feb 1993

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Comparable to guideline study with acceptable restrictions: No analytical monitoring of the test substance was performed. The vehicle concentration was set at 100 mg/L.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

yes

Remarks:

analytical monitoring was not performed.

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Controls: blank control and vehicle control
- Chemical name of vehicle: DMSO
- Concentration of vehicle in test medium (stock solution and final test solution): 100 mg/L

Test organisms (species):

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

Details on test organisms:

TEST ORGANISM
- Common name: Algae
- Strain: ATCC22662
- Source (laboratory, culture collection): Incorporated Administrative Agency, National Institute for Environmental Studies, Tsukuba, Japan

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test temperature:

23 ± 0.5 °C

pH:

7.3 - 10.1

Nominal and measured concentrations:

Nominal: 1, 2, 3, 4 and 5 mg/L

Details on test conditions:

OTHER TEST CONDITIONS
- Photoperiod: continuously light
- Light intensity and quality: 4000 lux

EFFECT PARAMETERS MEASURED: Algal growth after 72 h test duration.
- Determination of cell concentrations: Spectrophotometer

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 1.0
- Range finding study was performed
- Test concentrations: 0.1, 1, 10 and 100 mg/L
- Results used to determine the conditions for the definitive study: At 10 and 100 mg/L, cell proliferation was inhibited compared to control groups. At 0.1 and 1 mg/L, cell proliferation was as similar as for control groups.

Reference substance (positive control):

no

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

5.16 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

2.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Details on results:

- Exponential growth in the control: Yes

Reported statistics and error estimates:

Probit test

Table 1. Inhibition rate

Measured concentration [mg/L]	Inhibition rate [%] Growth rate	Inhibition rate [%] Biomass
Control	-	-
Solvent Control	- 5.3	- 14.6
1.0	- 10.9	-54.2
2.0	- 13.4	18.1
3.0	8.3	63.2
4.0	27.1	79.2
5.0	47.1	92.4

Description of key information

EC50 (72h) = 5.16 mg/L (nominal) for Pseudokirchnerella subcapitata (OECD 201)

NOEC (72h) = 3 mg/L (nominal) for Pseudokirchnerella subcapitata (OECD 201)

Key value for chemical safety assessment

EC50 for freshwater algae:

5.16 mg/L

EC10 or NOEC for freshwater algae:

3 mg/L

Additional information

One study investigating the toxicity to freshwater algae of Dibutyl adipate (CAS 105-99-7) is available. The study was conducted by a Japanese authority according to OECD guideline 201 using Pseudokirchnerella subcapitata as test organism (MOE, 1993). Test concentrations between 1 and 5 mg/L were applied. The test concentrations were prepared using DMSO as vehicle in a concentration of 100 mg/L. However, the high vehicle concentration is not considered to influence the outcome of the study as (i) the vehicle did not indicate to have any adverse effects on the test organisms and (ii) the substance has a water solubility higher than the tested concentrations (water solubility: 13 mg/L). The 72 h-EC50 was determined to be 5.16 mg/L and the 72 h-NOEC 3 mg/L based on nominal test concentrations.