Dimethyl adipate

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

supporting study

Study period:

1990-09-27 to 1990-10-02

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

(1984)

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

yes

Details on test solutions:

In order to facilitate the dispersion of the test item a vehicle (acetone R.P., lot 88161) was used at a final concentration of 0.1 mL/kg in the final assay, except for the solutions above 100 mg/L.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnid, water flea
- Strain: IRCHA
- Source: Laboratoire Ecotoxicologie du G.I.D.
- Length at study initiation: the test animals paased a mesh size of 800 µm but were detained in 560 µm mesh size
- Feeding during test: no

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

24 h

Test temperature:

20.0 to 20.2 °C

pH:

8.3 to 8.6 (see Table 1)

Dissolved oxygen:

95 to 100% (see Table 1)

Nominal and measured concentrations:

Nominal: 0, 39, 90, 120, 140, 200, 290, 440, 680 mg/L, reported as ppm (w/w)

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type: open
- Material, size, headspace, fill volume: 250 mL Pyrex glass beakers, fill volume 100 mL
- Aeration: No
- No. of organisms per vessel: 20
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- No. of vessels per vehicle control (replicates): 1


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water:
bidistilled water conductivity µS/cm
CaCl2 * 2 H2O: 0.297 g/L
MgCl2 * 6 H2O: 0.167 g/L
NaHCO3: 0.200 g/L
K2SO4: 0.026 g/L
(pH at 21 °C immediately before use: 8)
pH and dissolved oxygen were measured after the incuvbation period of 24 h


OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: incubation in the dark

EFFECT PARAMETERS MEASURED: immobility after 24 h

TEST CONCENTRATIONS
- Range finding study
- Test concentrations: 0.012, 0.035, 0.10, 0.31, 0.99, 3.6, 10, 31, 100, 390 mg/L
- Results used to determine the conditions for the definitive study: 24-h LC50 = 160 mg/L (ppm)

Reference substance (positive control):

yes

Remarks:

Potassium dichromate, CAS 7778-50-9, analytical grade

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

180 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: converted from ppm (w/w)

Duration:

24 h

Dose descriptor:

LOEC

Effect conc.:

140 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks:

- 10% immobility

Remarks on result:

other: converted from ppm (w/w)

Duration:

24 h

Dose descriptor:

NOEC

Effect conc.:

120 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: converted from ppm (w/w)

Results with reference substance (positive control):

The test animals were sensible and a LD50 to potassium dichromate of 1.4 mg/L was obtained (details are reported in the annexof study report D 79).

Reported statistics and error estimates:

The LC50 was determined graphically on logarithm paper

Table 1: Physical/chemical parameters and Immobilization

Concentrations [mg/L]	Immobilized animals		Oxygen saturation [%]	pH
	Number	%
Control	0	0	97	8.6
Solvent control	0	0	97	8.6
39	0	0	97	8.6
90	0	0	97	8.6
120	0	0	97	8.6
140	2	10	99	8.5
200	14	70	100	8.5
290	20	100	99	8.4
440	20	100	97	8.4
680	20	100	95	8.3

 Remark: Except in the 39 mg/L concentration the daphnids were swimming at the surface

Validity criteria fulfilled:

yes

Conclusions:

The acute toxicity to daphnids after 24 h was above the cut off limit of 100 mg/L.

Executive summary:

Daphnids (Daphnia magna) were exposed to Dibasic esters (DBE) in a dose response study according to the E.U. standards published on 19^th September 1994. The study was thus conducted similar to EU C.2 but compared to recent standards a shortened observation period is a relevant deviation. The study is however considered valid and conclusive for the derivation of a 24 -h LC₅₀.

The test animals were exposed to nominal concentrations of 0, 39, 90, 120, 140, 200, 290, 440, and 680 mg/L of the test item, reported as ppm (w/w). No analytical measurements of the tested concentrations was performed but due to the high solubility of the substance and in addition the use of a solvent, the stability of the substance is expected.

No mortality was observed in the control. The temperature, pH and the oxygen in the medium were maintained in the range recommended by the guidance document. The test item, DBE, exhibited low acute toxicity to daphnids during a 24 -hour exposure. The 24 -hour LC₅₀ is estimated to be greater than the cut of limit of 100 mg/L. An LC₅₀ of 180 mg/L was derived by graphical means. The NOEC was 120 mg/L and the LOEC 140 mg/L.

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: Office of Toxic Substances. U.S. Environmental Protection Agency Office of Pesticide Programs. Guideline for Testing of Chemicals. Guideline EG-1. Daphnid Acute Toxicity Test, August, 1982

Deviations:

no

Principles of method if other than guideline:

not applicable

GLP compliance:

yes

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
not applicable

Analytical monitoring:

yes

Details on sampling:

- Concentrations: dilution water control, 7.5, 15, 30, 60, and 120 mg/L (Nominal concentrations of Dimethyl adipate)
- Sampling method: One sample plus a back-up sample of each test solution was received from each test concentration including the control on day 0 of the test before the test solutions were poured into the replicate test chambers. One sample plus a back-up sample was also received from 2 of the 4 replicate chambers (C and D) at all test concentrations including the controls at test end (day 2).
- Sample storage conditions before analysis: measured on the day of receipt

Vehicle:

no

Details on test solutions:

The solubility of Dimethyl adipate (DMA) in a solution prepared in Haskell Laboratory well water (HLWW) at 20ºC was verified at 214 mg/L. The solubility of DMA in a solution prepared in HLWW at 10ºC was verified at 215 mg/L.

The stability of DMA in HLWW was demonstrated for 96 hours at approximately 20ºC and 4ºC.

Test substance solutions were prepared by dilution from a stock solution of DMA in Haskell Laboratory well water (HLWW). Nominal concentrations of test substance solutions were not adjusted for purity. The stock solution of 120 mg/L was prepared by weighing out the appropriate amount of test material and adding it to 1000 mL HLWW in a 2L Erlenmeyer flask. The final volume was brought to 2L with HLWW and stirred for approximately 2 hours. Test solutions were prepared by adding the appropriate volume of the stock solution to a 1L beaker, bringing it to a final volume of 1L with HLWW and stirring for approximately 23 minutes. The stock solution was clear and colorless with no insoluble material present. Test substance solutions were clear and colorless with no insoluble material present.

Dilution water originated from the Haskell Laboratory well about 378-feet deep and cased and sealed to bedrock. The hardness of the HLWW was adjusted to approximately 100-140 mg/L as CaCO3 by the flow-proportioned addition of CaCl2. The HLWW was then aerated, passed through a green sand filter to remove iron, and filtered through 50-, 10-, and 5-μm filters to remove particulates. The water was heated or chilled as appropriate and distributed through aged polyvinyl chloride piping. The dilution water was analyzed twice yearly for major anions and cations, metals, total organochlorine and organophosphate pesticides, and polychlorinated biphenyls and met the OECD and ASTM specifications.

Test organisms (species):

Daphnia magna

Details on test organisms:

Daphnia magna were reared at Haskell Laboratory in 1000-mL Pyrex beakers (10 per beaker) which contained 1000 mL of aerated, filtered HLWW held at 20.5°C. Daphnids were fed on a daily basis with a yeast, cereal leaves and trout chow (YCT) mixture (standardized to 1700- 2100 mg/L total solids) and the green alga, Selenastrum capricornutum, at a rate of 62,500 cells/mL of culture media. The combination of YCT and alga is equivalent to 0.1-0.2 mg total organic carbon per daphnid/day. Neonates used in this test were less than 24 hours old and were collected from the 7th and 10th brood of 20- and 28-day old parent daphnids, respectively. Sickness, injury, and abnormalities were not seen and ephippia were not being produced by the parent daphnids. No adult immobility was seen in the cultures used for testing during the 48-hour pretest period. Daphnia magna were identified by labels on the culture beakers and test chambers.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

not applicable

Hardness:

120-124 mg/L CaCO3

Test temperature:

Mean temperature was 20.0°C with a range of 19.9 to 20.2°C.

pH:

pH ranged from 7.5 to 8.0

Dissolved oxygen:

Dissolved oxygen concentrations ranged from 8.3 to 9.0 mg/L

Salinity:

not applicable

Nominal and measured concentrations:

nominal concentrations - dilution water control, 7.5, 15, 30, 60, and 120 mg/L
mean measured concentrations - not detected, 6.9, 14, 29, 58, and 120 mg/L

Details on test conditions:

Five nominal concentrations and a dilution water control were used in this study. Nominal concentrations of DMA (not adjusted for 98.8% purity) of 7.5, 15, 30, 60, and 120 mg/L were chosen for the definitive test based on the results of a preliminary range finding study. The dilution water control contained no solvent.

Pyrex beakers (250-mL) containing 200 mL of test solution (6.8-cm test solution depth) were used as test chambers. Four replicate test chambers were used per test concentration with 5 daphnids in each chamber (20 daphnids per concentration). The test chambers were covered with a glass plate during the test. Random numbers were used to assign test concentrations to the test chambers and position of test concentrations in the water bath.

Daphnia magna neonates, less than 24 hours old, were used in this study. Daphnids were assigned to the test chambers using random numbers. Addition of daphnids to test solutions was initiated about 57 minutes after mixing of the test solutions was completed. Observations of test organisms were made daily. The criterion for the effect (immobility) was a lack of reaction to application of a gentle stimulus. Daphnids were not fed during the test.

A recirculating water bath was used to maintain mean temperature in the test chambers during the 48-hour test at approximately 20.0°C with a range of 19.9 to 20.2 °C. In addition, a continuously-recording thermometer was used to check for temperature variation in the water bath. A photoperiod of 16 hours light (approximately 346 - 674 lux) and 8 hours darkness was employed which included 30 minutes of transitional light (18 - 57 lux) preceding and following the 16-hour light interval.

Dissolved oxygen concentration, pH, and temperature were measured in all replicates of the control and test substance concentrations. These measurements were taken before daphnids were added at test start, and at test end or at total immobility in a concentration. Total alkalinity, EDTA hardness, and conductivity of the dilution water controls and highest test substance concentration were measured before daphnids were added at the beginning of the test. Test solutions were not aerated during the test and were disposed of in an appropriate manner at test end.

Reference substance (positive control):

not required

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

72 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CL - 61-88 mg/l

Details on results:

Exposure of daphnids to mean, measured Dimethyl adipate concentrations of 6.9, 14, 29, 58, and 120 mg/L resulted in 0, 0, 0, 10, and 100% immobility, respectively, at the end of the 48 hours. No immobility or sublethal effects were observed in the dilution water control or the mean, measured concentration of 6.9 mg/L. Floating daphnids (2 out of 20) were observed in the 14 mg/L mean, measured test concentration at the end of the study. In the 29 mg/L mean, measured test concentration lethargic daphnids (2 out of 20) were observed at the end of the study. In the 58 mg/L mean, measured test concentration, lethargic daphnids (15 out of 18) and lethargic and pale daphnids (2 out of 18) were observed at the end of the study.

The 24-hour EC50, based on mean, measured concentrations of Dimethyl adiapte , was 119 mg/L with 95% fiducial limits of 103 to 148 mg/L. The 48-hour EC50, based on mean, measured concentration of Dimethyl adipate, was 72 mg/L with 95% confidence limits of 61 to 88 mg/L. The highest mean, measured concentration causing no immobility at test end was 29 mg/L. The lowest mean, measured concentration causing 100% immobility at test end was 120 mg/L.

Results with reference substance (positive control):

not applicable

Reported statistics and error estimates:

The 24-hour EC50 value was calculated by probit analysis based on mean, measured Dimethyl adipate concentrations. The 48-hour EC50 value was calculated by the moving average-angle method based on mean, measured Dimethyl adipate concentrations.

None

Validity criteria fulfilled:

yes

Conclusions:

DMA was assessed for acute toxicity to unfed Daphnia magna neonates, less than 24 hours old, in an unaerated, static, 48-hour test. The 48-hour EC50, based on mean, measured concentrations of DMA and immobility, was 72 mg/L with 95% confidence limits of 61 to 88 mg/L.

Executive summary:

The acute toxicity of Dimethyl Adipate (DMA) to unfed Daphnia magna neonates, less than 24 hours old at test start, was determined in an unaerated, 48-hour, static test. The test was conducted in accordance with the Organisation for Economic Co-Operation and Development (OECD) Guideline for Testing Chemicals: 202; the European Economic Community 92/69 Annex V - Method C.2; and the United States Environmental Protection Agency, Office of Toxic Substances. The study was conducted with 5 concentrations of DMA and a dilution water control at a mean temperature of 20.0°C (range of 19.9-20.2°C). Four replicates with 5 daphnids per replicate were used per test substance concentration and control. Exposure of daphnids to mean, measured DMA concentrations of 6.9, 14, 29, 58, and 120 mg/L resulted in 0, 0, 0, 10, and 100% immobility, respectively, at the end of 48 hours. Mean, measured concentrations ranged from 92 to 100% of the nominal concentrations adjusted for 98.8% purity by analysis. No immobility or sublethal effects were observed in the dilution water control daphnids. The highest mean, measured concentration causing no immobility at test end was 29 mg/L. The lowest mean, measured concentration causing 100% immobility at test end was 120 mg/L. Mean, measured DMA concentrations were used for calculation of EC50 values. The 48-hour EC50, based on mean, measured concentrations of DMA and immobility, was 72 mg/L with 95% confidence limits of 61 to 88 mg/L.

Reference 3

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

supporting study

Study period:

1982-04-21 to 1982-04-23

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Qualifier:

equivalent or similar to guideline

Guideline:

EPA OTS 797.1300 (Aquatic Invertebrate Acute Toxicity Test, Freshwater Daphnids)

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

The test material, in original form and prepared as a stock solution, was diluted with laboratory-aged well water to yield the desired exposure concentrations. After mixing, 200 mL volumes of each concentration were introduced into each of two separate 250 mL glass exposure vessels. Two identical jars, containing only laboratory-aged well water, were designated as controls.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnid, water flea
- Age at study initiation: 24 h
- Feeding during test: no

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

EDTA Hardness: 142 mg/L as CaCO3 at 0 h

Test temperature:

20 °C

pH:

0 h 7.7, control 7.6
24 h 7.6
48 h 7.2 to 7.4, control 7.5
Total Alkalinity: 136 mg/L as CaCO3 at 0 h

Dissolved oxygen:

0 h 9.2 to 9.4 mg/L
24 h 8.8 mg/L
48 h 7.0 to 7.5 mg/L, control 8.6 mg/L

Salinity:

Conductivity: 225 umhos (= micro ohms per cm or decisiemens per m [dS/m])

Nominal and measured concentrations:

nominal 0, 20, 27, 36, 47, 63, 84, 112, 150, 200 ppm(v/v)

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: 250 mL glass vessels, 200 mL fill volume
- Aeration: no
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2

TEST MEDIUM / WATER PARAMETERS
Dissolved oxygen and pH were measured in the control, low and medium test concentrations at the beginning and end of exposure. Dissolved oxygen and pH were measured in the high test concentration at the beginning of the test and at 24 hours after the exposure was initiated. The total alkalinity, hardness (EDTA) and conductivity of the control were measured at the beginning of the exposure in the control.

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: maintained at 16 hour light : 8 hours dark

EFFECT PARAMETERS MEASURED:
Mortality counts and observations were made at 24 and 48 hours after the exposure was initiated.

Reference substance (positive control):

not specified

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 112 - < 150 other: ppm (v/v)

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: No no mass based concentrations or density is given in the study report

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

84 other: ppm (v/v)

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: No no mass based concentrations or density is given in the study report

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

112 other: ppm (v/v)

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks:

- 25% immobility

Remarks on result:

other: No no mass based concentrations or density is given in the study report

Details on results:

Percent mortalities for Daphnia magna exposed to the test item, DBE, are presented in Table I.

Table I: Mortality count (immobilisation)

Nominal concentration [mg/L]	Observed Mortality [%] in replicate exposure chambers A and B containing 10 daphnids each
	24 h		48 h
	A	B	A	B
200	100	100	100	100
150	70	80	100	90
112	0	0	20	30
84	0	0	0	0
63	0	0	0	0
47	0	0	0	0
36	0	0	0	0
27	0	0	0	0
20	0	0	0	0
Control	0	0	0	0

 

Validity criteria fulfilled:

yes

Remarks:

According to OECD guideline criteria

Conclusions:

The 48-hour LC50 of DBE is estimated to be greater than 112 ppm (v/v) but less than 150 ppm (v/v).

Executive summary:

Daphnids (Daphnia magna) were exposed to Dibasic esters (DBE) with the test medium. No mass based concentrations or density is given in the study report. No GLP statement is made. The protocol applied is comparable to EPA OTS 797.1300 (Fish Acute Toxicity Test). The study is however considered valid and conclusive since the density of the test item is considered not different from standard material.

The test animals were exposed to nominal concentrations of 0, 20, 27, 36, 47, 63, 84, 112, 150, and 200 ppm(v/v). No analytical measurements of the tested concentrations was performed but due to the high solubility of the substance it is expected to be stable during the test.

No mortality was observed in the control. The temperature and the oxygen in the medium were maintained in the range recommended by the guidance document. The test item, DBE, exhibited slight acute toxicity to daphnids (Daphnia magna) under static, unaeriated test conditions during a 48-hour exposure. The NOEC was at 84 ppm (v/v) and the LOEC at 112 ppm (v/v), where 25% mortality was observed. Thus the 48-hour LC₅₀is estimated to be greater than 112 ppm (v/v) but less than 150 ppm (v/v) in laboratory-aged well water.

Description of key information

The 48-hour LC50 for dimethyl adipate was determined to be 72 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

72 mg/L

Additional information

Justification for Read Across

Attached at section 13 is a category justification that explains the rationale for using data on a mixture of Dimethyl Esters (DBE), and Dimethyl Glutarate, to supplement the available data on Dimethyl Adipate.

In the key study (Dupont, 2003), exposure of daphnids to mean, measured Dimethyl adipate concentrations of 6.9, 14, 29, 58, and 120 mg/L resulted in 0, 0, 0, 10, and 100% immobility, respectively, at the end of the 48 hours. No immobility or sublethal effects were observed in the dilution water control or the mean, measured concentration of 6.9 mg/L. The 48-hour EC50, based on mean, measured concentrations of dimethyl adipate and immobility, was 72 mg/L with 95% confidence limits of 61 to 88 mg/L.

Two supporting studies are available for this endpoint. In one study ( Phillips FX, 1982) Daphnids (Daphnia magna) were exposed to Dibasic esters (DBE) with the test medium. The test item, DBE, exhibited slight acute toxicity to daphnids (Daphnia magna) under static, unaeriated test conditions during a 48-hour exposure. The NOEC was at 84 ppm (v/v) and the LOEC at 112 ppm (v/v), where 25% mortality was observed. Thus the 48-hour LC₅₀is estimated to be greater than 112 ppm (v/v) but less than 150 ppm (v/v) in laboratory-aged well water. The second supporting study (Gard A, 1990) was performed with only 24h of exposure, but showed a 24hEC50 above 100 mg/L.