Dibutyl adipate

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

22 Feb - 26 Feb 1982

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Comparable to guideline study with acceptable restrictions: Samples were not taken at 0 hours, nor were nominal concentrations reported. It was not stated if GLC analysis were performed by either direct aqueous injection or solvent extraction and subsequent analysis.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

two replicates tested with 20 fish each

GLP compliance:

not specified

Analytical monitoring:

yes

Details on sampling:

- Concentrations: Samples were taken in all test concentrations.
- Sampling method: Samples were taken after 24 h and 72 h in replicate 1 and after 48 h and 96 h in replicate 2 of each test concentration.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Lake Superior water plus the test substance were added to the vessels and stirred vigorously.

Test organisms (species):

Pimephales promelas

Details on test organisms:

TEST ORGANISM
- Common name: fathead minnow
- Source: US-EPA Environmental Research Laboratory-Duluth
- Age at study initiation: 33 days
- Weight at study initiation: 0.32 g
- Method of breeding: Adults were held at 25 °C in flowing water with a 16 h light controlled photoperiod and fed frozen adult brine shrimp (Artemis spec.). Asbestos pipe was used as spawning substrate. Eggs were spawned and fertilized on the underside of these substrates. Substrates with embryos attached were removed to another 25 °C bath where hatching occurred.
- Feeding during test: Test fish were not fed 24 h before or during test.

ACCLIMATION
- Acclimation period: Fry of similar age (within 24 h) were transferred to flow-through rearing tanks at 25 °C with a 16h light photoperiod.
- Acclimation conditions: same as test
- Type and amount of food: Larvae were fed 40-48 h old brine shrimp nauplii
- Feeding frequency: two times daily (once on weekend days)
- Health during acclimation: Only groups of fish having healthy appearance were used for the test.

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

47 mg/L as CaCO3

Test temperature:

24.5 ± 0.46 °C

pH:

7.51 ± 0.09

Dissolved oxygen:

8.0 mg/L

Nominal and measured concentrations:

Nominal: not stated
Measured (arith. mean): 0.91, 1.43, 2.38, 4.70 and 9.09 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: fish tank
- Fill volume: 7.3 L
- Type of flow-through: cycling proportional diluter
- Renewal rate of test solution: 19.7 chamber volumes were added per day
- No. of organisms per vessel: 20
- No. of vessels per concentration: 2
- No. of vessels per control: 2
- Biomass loading rate: 0.044 g/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Lake Superior water which was filtered through sand and a FRAM filter.
- Metals: Zinc: 1.0 - 2.7 µg/L; Nickel: > 0.5 µg/L; Manganese: 0.2 - 11.5 µg/L; Lead: 7-20 µg/L; Iron: 2-83 µg/L; Cobalt: < 0.5 µg/L; Chromium: 2-20 µg/L; Cadmium: < 0.1 µg/L; Aluminium: 1-26 µg/L; Potassium: 0.48 - 0.59 mg/L; Magnesium: 2.9-3.6 mg/L; Calcium: 13.0-14.7 mg/L; Sodium: 1.1-1.2 mg/L
- Chlorine: 1.2 - 1.3 mg/L
- Alkalinity: 43.3 mg/L as CaCO3
- Ca/mg ratio: 3.6 - 5.0
- Conductivity: 78 - 86 µmhos/cm
- Intervals of water quality measurement: Temperature, dissolved oxygen, pH, total hardness and alkalinity were measured routinely. Temperature was monitored with a recording thermometer from which daily averages were calculated and recorded for a single tank. Dissolved oxygen was measured in low, medium, high concentration and control vessels at least once during the test. Total hardness and alkalinity were measured once during the test in the control and at low, medium and high test concentrations. The EDTA method (APHA, 1980) was used to determine hardness, while alkalinity was determined by potentiometric titration (APHA, 1980). The pH-value was measured once in high, medium, low and control treatments. Measurements were made with a meter, calibrated prior to each test.

OTHER TEST CONDITIONS
- Photoperiod: 16 h/8 h light/dark
- Light intensity: Illumination, provided by a fluorscent source, produced 28-48 lumens at the water surface.

EFFECT PARAMETERS MEASURED: Mortality and behavioral abnormalities were recorded after 24, 48 and 96 h test duration. Additionally, upon test termination, subsamples of control fish were weighed en masse.

Reference substance (positive control):

yes

Remarks:

Numerous substances were tested using the same test design with same substances showing high toxicity

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

3.64 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 3.39 - 3.90 mg/L

Details on results:

- Behavioural abnormalities: Affected fish swam near the bottom and lost equilibrium prior to death.

Results with reference substance (positive control):

Several substances showed to be very toxic to fish, such as Hexachloro-1,3-butadiene with LC50 = 0.09 mg/L or Chloromethyl Styrene with LC50 = 0.31 mg/L.

Sublethal observations / clinical signs:

Table 1: Measured concentration of the test substance

Test concentration	Measured tank concentrations [mg/L]
	0h	24h	48h	72h	96h	average	Corrected average
Control (Replicate 1/2)	-	< 0.5 / -	-. / < 0.5	< 0.5 / -	- / < 0.5	< 0.5	< 0.5
Test conc. 1 (Replicate 1/2)	-	1.11 / -	- / 0.71	0.90 / -	- / 0.91	0.91	0.91
Test conc. 2 (Replicate 1/2)	-	1.92 / -	- / 1.19	1.20 / -	- / 1.44	1.44	1.43
Test conc. 3 (Replicate 1/2)	-	2.94 / -	- / 1.88	2.50 / -	- / 2.27	2.40	2.38
Test conc. 4 (Replicate 1/2)	-	5.78 / -	- / 3.75	4.76 / -	- / 4.62	4.73	4.70
Test conc. 5 (Replicate 1/2)		10.7 / -	- / 7.83	9.32 / -	- / 8.72	9.14	9.09

Table 2: Mortalities

Test concentration	Mortalities (initial number of fishes: 20 per replicate)
	24h	48h	96h
Control (Replicate 1/2)	0 / 0	0 / 0	0 / 0
Test conc. 1 (Replicate 1/2)	0 / 0	0 / 0	0 / 0
Test conc. 2 (Replicate 1/2)	0 / 0	0 / 0	0 / 0
Test conc. 3 (Replicate 1/2)	0 / 0	0 / 0	0 / 0
Test conc. 4 (Replicate 1/2)	10 / 17	16 / 19	16 / 19
Test conc. 5 (Replicate 1/2)	20 / 20	20 / 20	20 / 20

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02 Aug - 06 Aug 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 for the pretest, but at 200 mg/L for the main test; no explanation was provided.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

No analytic was performed and vehicle concentration was 200 mg/L

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: mixture of DMSO and HC40 (DMSO : HC40 = 9:1)
- Concentration of vehicle in test medium (stock solution and final test solution): 100 mg/L for the pretest and 200 mg/L for the main test

Test organisms (species):

Oryzias latipes

Details on test organisms:

TEST ORGANISM
- Common name: Medaka
- Length at study initiation: 2.02 (1.8 - 2.4) cm
- Weight at study initiation (mean): 0.073 g

ACCLIMATION
- Type and amount of food: mixed food
- Feeding frequency: twice a day
- Health during acclimation: Mortality was mentioned to be low, but not further specified.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

64

Test temperature:

22 ± 0.5 °C

pH:

7.6 - 7.9

Dissolved oxygen:

5.4 - 8.4 mg/L

Nominal and measured concentrations:

Nominal concentration: 1, 1.8, 3.2, 5.6 and 10 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: not specified
- Size: 4 L
- Renewal rate of test solution: once a day
- No. of organisms per vessel: 10
- No. of vessels per concentration: 1
- No. of vessels per control: 1
- No. of vessels per vehicle control: 1

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: dechlorinated tap water
- Alkalinity: 26.5
- Ca/Mg ratio: 8.2

OTHER TEST CONDITIONS
- Photoperiod: 16 hours in the light, 8 hours in the dark
- Light intensity: 3500 lux

EFFECT PARAMETERS MEASURED: Mortality was recorded after 96h test duration.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 1.8
- Range finding study was performed
- Test concentrations: 0.1, 1, 10 and 100 mg/L (vehicle concentration was 100 mg/L)
- Results used to determine the conditions for the definitive study: 100% mortality was observed in 10 and 100 mg/L. In 1 mg/L group, mortality was 20%.

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

3.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 2.85 - 4.83 mg/L

Details on results:

- Mortality of control: 0% in blank control and vehicle control

Reported statistics and error estimates:

Probit test

Sublethal observations / clinical signs:

Table 1. Mortality

Nominal concentration [mg/L]	Vehicle concentration [mg/L]	Cumulative Number of Dead (Percent Mortality)
		24 h	48 h	72 h	96 h
Control	-	0 (0)	0 (0)	0 (0)	0 (0)
Solvent Control	200	0 (0)	0 (0)	0 (0)	0 (0)
1	200	0 (0)	0 (0)	0 (0)	0 (0)
1.8	200	0 (0)	1 (10)	1 (10)	1 (10)
3.2	200	0 (0)	0 (0)	2 (20)	2 (20)
5.6	200	7 (70)	9 (90)	9 (90)	9 (90)
10	200	10 (100)	10 (100)	10 (100)	10 (100)

Description of key information

LC50 (96h) = 3.64 mg/L (measured) for Pimephales promelas

LC50 (96h) = 3.7 mg/L (nominal) for Oryzias latipes

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

3.64 mg/L

Additional information

Two studies investigating the short-term toxicity to freshwater fish of Dibutyl adipate (CAS 105-99-7) are available. One semi-static study was conducted by a Japanese authority according to OECD guideline 203 using Oryzias latipes as test organism (MOE, 1993). Test concentrations between 1 and 10 mg/L were applied. The test concentrations were prepared using a very high vehicle concentration (200 mg/L); however, this is not considered to influence the outcome of the study as (i) the vehicle did not indicate any adverse effects on the test organisms and (ii) the test substance has a water solubility higher than the tested concentrations (water solubility: 35 mg/L). The 96 h-LC50 was determined to be 3.7 mg/L based on the nominal test concentration. This result is confirmed by a second study, which was conducted under flow-through conditions according to OECD guideline 203 using Pimephales promelas as test organism (Geiger et al., 1985). The applied test concentrations were measured to be between 0.91 and 9.09 mg/L using GLC analysis. The 96 h-LC50 was determined to be 3.64 mg/L based on the measured concentrations.