citric acid, esters with dodecan-1-ol

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:

experimental study

Adequacy of study:

key study

Study period:

1999-01-25 to 1999-01-27

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP guideline study, read-across

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

yes

Remarks:

Age of test organisms: The test was started 25.5 hours after discarding of the young Daphnia from the breeding. Therefore it might be possible that some of hte test animals were slightly older than 24 hours. Presumed effect on the study: none

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
PHYSICO-CHEMICAL PROPERTIES
- Melting point: -29°C (freezing point: -35.5°C)
- Boiling point: test substance showed decomposition above 260°C
- Vapour pressure: 8.5 x 10E-3 p at 25°C
- Water solubility (under test conditions): < 1 mg/L
- Solubility in organic solvents: soluble
- log Pow: > 6
- pKa: not applicable
- Base or acid catalysis of test material: no data
- UV absorption: no data
- Stability of test material at room temperature: stable
- pH dependance on stability: no data


OTHER PROPERTIES (if relevant for this endpoint)
- Adsorption characteristics: no data

Analytical monitoring:

no

Details on sampling:

In a pre-experiment (without GLP) the dissolved organic carbon contents (DOC) of the test substance solution (same preparation as in the test) was determined. In the solution the same amount of DOC was determined as in the blank control. Thus, no dissolved test substance could be verified in test water. Therefore, no analytical dose verification in the test media of the acute toxicity test with Daphnia could be done.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: A supersaturated stock suspension of the test substance with a nominal concentration of 100 mg/L was prepared by weighing 503 mg of the test substance into 5 L test water, following ultrasonic treatment for 10 minutes and intense stirring. The supersaturated stock suspension was stirred on a magnetic stirrer at room temperauter in the dark over 3 days . Thereafter the suspension was filtered through a cellulose-nitrate filter with a defined pore size of 0.2 µm just before the start of the test.
- Controls: test water
- Evidence of undissolved material (e.g. precipitate, surface film, etc): no, suspension was filtered

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Strain: Daphnia magna (Straus), clone 5
- Source: Umweltbundesamt, Institut for Wasser-, Boden- und Lufthygiene, Berlin, Germany
- Age at study initiation (mean and range, SD): 7 - 25.5 hours
- Method of breeding: under similar temperature and light conditions as in the test, and in reconstituted water of a similat quality regarding pH, components of the mian ions and total hardness as the test water used in the test, the test organisms were not first brood progeny
- Feeding during test: none


ACCLIMATION
- Acclimation period: 7 hours
- Acclimation conditions: same as test
- Type and amount of food: not fed
- Health during acclimation (any mortality observed): not mentioned

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

2.5 mmol/L (= 250.0 mg/L) as CaCO3

Test temperature:

21 °C

pH:

7.6 - 7.8

Dissolved oxygen:

7.6 - 8.9 mg/L

Salinity:

In deionized water (conductivity < 5 µS/cm) analytical grade salts were added to following nominal concentrations:
2.0 mmol/L (= 294 mg/L) CaCl2 x 2 H2O
0.5 mmol/L (= 123 mg/L) MgSO4 x 7 H2O
0.75 mmol/L (= 65.0 mg/L= NaHCO3
0.075 mmol/L =(= 5.8 mg/L) KCl

Nominal and measured concentrations:

WAF, no analytical determination of test substance concentration

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass beakers of 100 mL volume with 50 mL test medium
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: reconstituted water
- Ca/mg ratio: 4:1 (based on molarity)
- Culture medium different from test medium: no
- Intervals of water quality measurement: not mentioned


OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 h light
- Light intensity: 1178 lux


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Immobility or mortalitiy of the Daphnia was determined by visual controls after 24 and 48 hours. Measurement of pH, dissolved oxygen and water temperature at test start and end of test. The behaviour of the test substance in test water was determined at the start of the test, after 24 and 48 hours.

Reference substance (positive control):

yes

Remarks:

potassium dichromate, tested at least twice a year

Key result

Duration:

48 h

Dose descriptor:

EC50

Nominal / measured:

nominal

Conc. based on:

test mat. (total fraction)

Basis for effect:

mobility

Remarks on result:

not determinable

Remarks:

The 48-hour EC50 was clearly higher than the solubility limit of the test substance

Details on results:

After 24 and 48 hours in the control and in the undiluted filtrate of the supersaturated stock suspension no mortality or immobilization of the test animals was observed.
No remarkable observations were made concerning the behaviour of the test substance in the filtrate.

Results with reference substance (positive control):

not mentioned

Reported statistics and error estimates:

The EC50 and EYC 100 could not be quantified due to the absence of toxicity of the test substance up to the water solubility

Table: Influence of test substance on the mobility of Daphnia magna

Treatment	No. of Daphnia tested	No. of immobilized Daphnia after		% of immobilized Daphnia after
		24 h	48 h	24 h	48 h
control	20	0	0	0	0
filtrate of test substance	20	0	0	0	0

Validity criteria fulfilled:

yes

Remarks:

Mortality of Daphnia magni in the control did not exceed 10 % and no Daphnia were trapped at the water surface.

Conclusions:

Due to low water solubility of the test substance a filtrate of a supersaturated stock suspension of nominal 100 mg/L was tested. Thus no concentrations above the solubility limit of the test substance in the used test water were tested. Due to the low water solubility limit no analytical dose verfication could be done in the present test. Therefore, the biological results could not be related to a specific concentration but to the solubility limit of Tri (hexyl, octyl, decyl) citrate in the test medium.
The 48-hour NOEC, respectively the 48-hour EC0 of the test substance to Daphnia magna were determined to be at least up to the solubility limit. The NOEC and the EC0 might even be higher, but concentrations in excess of the solubility limit had not been tested. The 48-hour EC50 was clearly higher than the solubility limit of the test substance in the used test water.

Executive summary:

The acute toxicity of the read-across substance Tri (hexyl, octyl, decyl) citrate to Daphnia magna was determined in a 48-hour static test according to OECD Guideline for Testing of Chemicals No. 202, Part I, adopted April 04, 1984. The test was performed in compliance with GLP.

Due to low water solubility of the test substance a filtrate of a supersaturated stock suspension of nominal 100 mg/L was tested. Thus no concentrations above the solubility limit of the test substance in the used test water were tested. Due to the low water solubility limit no analytical dose verfication could be done in the present test. Therefore, the biological results could not be related to a specific concentration but to the solubility limit of Tri (hexyl, octyl, decyl) citrate in the test medium.

The 48-hour NOEC, respectively the 48-hour EC0 of the test substance to Daphnia magna were determined to be at least up to the solubility limit. The NOEC and the EC0 might even be higher, but concentrations in excess of the solubility limit had not been tested. The 48-hour EC50 was clearly higher than the solubility limit of the test substance in the used test water.

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP guideline study, read-across

Justification for type of information:

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
This read across is based on the hypothesis that source and target substance have similar toxicological and ecotoxicological properties, because
- they are manufactured from similar/identical precursors under similar conditions
- they share structural similarities with common functional groups: ester bonds and fatty alcohol chains varying in length

Therefore, read across from the existing physical-chemical, toxicological and ecotoxicological studies on the source substance is considered as an appropriate adaptation to the standard information requirements of the REACH Regulation for the target substance , in accordance with the provisions of Annex XI, 1.5 of the REACH Regulation.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
The source substance 2-Hydroxypropan-1,2,3-tricarboxylic acid, tri (hexyl, octyl, decyl esters) is a UVCB substance manufactured from 2-Hydroxypropan-1,2,3-tricarboxylic acid and C6-10 fatty alcohols.
The target substance Reaction mass of didodecyl hydrogen citrate and tridodecyl 2-hydroxypropane-1,2,3-tricarboxylate is a multi constituent substance manufactured from 2-Hydroxypropan-1,2,3-tricarboxylic acid and 1-dodecyl alcohol.


3. ANALOGUE APPROACH JUSTIFICATION
The read-across hypothesis is based on structural similarity of the target and source substance. Based on available experimental data, including key physicochemical properties and a genotoxicity study, the read-across strategy is supported by a similar toxicological profile of the target and source substance.
The respective reliable data (RL 1 or 2) are summarized in the data matrix; robust study summaries are included in the Technical Dossier in the respective sections.
The read-across from the source substance is justified:
a) Based on the information given in section 1, it can be concluded that the substances are similar in structure, since they are manufactured from similar or identical precursors under similar conditions and all contain the same functional groups. Thus a common mode of action can be assumed.
c) The only difference within the two substances is a (minor) variation in the chain length of the alcohols used for manufacture, which is not expected to have a relevant impact on intrinsic toxic or ecotoxic activity and environmental fate.

4. DATA MATRIX
See document under "Attached justification".

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

yes

Remarks:

Age of test organisms: The test was started 25.5 hours after discarding of the young Daphnia from the breeding. Therefore it might be possible that some of hte test animals were slightly older than 24 hours. Presumed effect on the study: none

GLP compliance:

yes (incl. QA statement)

Details on sampling:

In a pre-experiment (without GLP) the dissolved organic carbon contents (DOC) of the test substance solution (same preparation as in the test) was determined. In the solution the same amount of DOC was determined as in the blank control. Thus, no dissolved test substance could be verified in test water. Therefore, no analytical dose verification in the test media of the acute toxicity test with Daphnia could be done.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Strain: Daphnia magna (Straus), clone 5
- Source: Umweltbundesamt, Institut for Wasser-, Boden- und Lufthygiene, Berlin, Germany
- Age at study initiation (mean and range, SD): 7 - 25.5 hours
- Method of breeding: under similar temperature and light conditions as in the test, and in reconstituted water of a similat quality regarding pH, components of the mian ions and total hardness as the test water used in the test, the test organisms were not first brood progeny
- Feeding during test: none


ACCLIMATION
- Acclimation period: 7 hours
- Acclimation conditions: same as test
- Type and amount of food: not fed
- Health during acclimation (any mortality observed): not mentioned

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Nominal and measured concentrations:

WAF, no analytical determination of test substance concentration

Key result

Duration:

48 h

Dose descriptor:

EC50

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

not determinable

Remarks:

The 48-hour EC50 was clearly higher than the solubility limit of the test substance

Details on results:

After 24 and 48 hours in the control and in the undiluted filtrate of the supersaturated stock suspension no mortality or immobilization of the test animals was observed.
No remarkable observations were made concerning the behaviour of the test substance in the filtrate.

Results with reference substance (positive control):

not mentioned

Reported statistics and error estimates:

The EC50 and EYC 100 could not be quantified due to the absence of toxicity of the test substance up to the water solubility

Table: Influence of test substance on the mobility of Daphnia magna

Treatment	No. of Daphnia tested	No. of immobilized Daphnia after		% of immobilized Daphnia after
		24 h	48 h	24 h	48 h
control	20	0	0	0	0
filtrate of test substance	20	0	0	0	0

Validity criteria fulfilled:

yes

Remarks:

Mortality of Daphnia magni in the control did not exceed 10 % and no Daphnia were trapped at the water surface.

Conclusions:

Due to low water solubility of the test substance a filtrate of a supersaturated stock suspension of nominal 100 mg/L was tested. Thus no concentrations above the solubility limit of the test substance in the used test water were tested. Due to the low water solubility limit no analytical dose verfication could be done in the present test. Therefore, the biological results could not be related to a specific concentration but to the solubility limit of Tri (hexyl, octyl, decyl) citrate in the test medium.
The 48-hour NOEC, respectively the 48-hour EC0 of the test substance to Daphnia magna were determined to be at least up to the solubility limit. The NOEC and the EC0 might even be higher, but concentrations in excess of the solubility limit had not been tested. The 48-hour EC50 was clearly higher than the solubility limit of the test substance in the used test water.

Executive summary:

The acute toxicity of the read-across substance Tri (hexyl, octyl, decyl) citrate to Daphnia magna was determined in a 48-hour static test according to OECD Guideline for Testing of Chemicals No. 202, Part I, adopted April 04, 1984. The test was performed in compliance with GLP.

Due to low water solubility of the test substance a filtrate of a supersaturated stock suspension of nominal 100 mg/L was tested. Thus no concentrations above the solubility limit of the test substance in the used test water were tested. Due to the low water solubility limit no analytical dose verfication could be done in the present test. Therefore, the biological results could not be related to a specific concentration but to the solubility limit of Tri (hexyl, octyl, decyl) citrate in the test medium.

The 48-hour NOEC, respectively the 48-hour EC0 of the test substance to Daphnia magna were determined to be at least up to the solubility limit. The NOEC and the EC0 might even be higher, but concentrations in excess of the solubility limit had not been tested. The 48-hour EC50 was clearly higher than the solubility limit of the test substance in the used test water.

Description of key information

The 48-hour NOEC, respectively the 48-hour EC0 of the test substance to Daphnia magna were determined to be at least up to the solubility limit. The NOEC and the EC0 might even be higher, but concentrations in excess of the solubility limit had not been tested. The 48-hour EC50 was clearly higher than the solubility limit of the test substance in the used test water.