Phosphoric acid C12-alkyl and C18-alkyl esters, potassium salts

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:

weight of evidence

Study period:

February 2003

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

not specified

GLP compliance:

yes

Remarks:

certificate not available

Analytical monitoring:

yes

Vehicle:

no

Details on test solutions:

Stock Solution with concentration of 10.000 mg/L was preapred. The solution was a cloudy liquid.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain: Straus
- Source: Umwelt-Bundesamt, 12307 Berlin
- Age at study initiation: 6 - 24 h
- Feeding during test: yes
- Food type: Scenedesmus subspicatus

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test temperature:

20.1 °C

pH:

7.7 (7.2 - 7.8)

Dissolved oxygen:

65.5 %
0 h: 5.9 to 7.3
48 h: 5.1 to 6.1

Nominal and measured concentrations:

Nominal concentrations: 0, 100, 1000, 1500, 2000, 2500, 5000 mg/L
No measured concentrations reported.

Details on test conditions:

In the highest test concentrations (5000, 2500 and 2000 mg/L) adsorption to the glass vessel was observed. At the water surface a white film was formed.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

740 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

1 340 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Validity criteria fulfilled:

yes

Conclusions:

The 48-Hour EC50 for the test item to Daphnia magna based on nominal concentration was 1340 mg/L. EC50 value was above the water solubility of the test item.

Executive summary:

Introduction

A study was performed to assess the acute toxicity of the test item to Daphnia magna. The method followed was designed to be compatible with the OECD Guidelines for Testing of Chemicals No 202, "Daphnia sp, Acute Immobilisation Test" referenced as Method C.2 of Commission Regulation (EC) No. 440/2008.

Methods

Twenty daphnids per concentration (4 replicates of 5 animals) were exposed to the test item, at 6 nominal loading rates of 100, 1000, 1500, 2000, 2500, 5000 mg/L for 48 hours at a temperature of 21 to 22 ºC under static test conditions. Immobilisation and any adverse reactions to exposure were recorded after 24 and 48 hours.

Results

The 48-Hour EC50 for the test item to Daphnia magna based on nominal concentration was 1340 mg/L. EC50 value was above the water solubility.

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

from 2012-02-13 to 2012-03-22

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline 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:

ISO 6341 (Water quality - Determination of the Inhibition of the Mobility of Daphnia magna Straus (Cladocera, Crustacea))

Version / remarks:

June 1996

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Details on sampling:

Analyses of DOC (dissolved organic carbon) were made by TC/IC (total carbon/inorganic carbon) measurement using the carbon analyser TOC multi N/C 2100 S (Analytik Jena AG). Samples were taken after preparation of the treatments at the start of the test and at the end of the test and were filtrated with membrane filters (pore diameter 0.45 µm). The samples were measured directly. Each sample was measured at least in duplicate.

Vehicle:

no

Details on test solutions:

A water-accommodation fraction (WAF) was prepared by weighing the nominal load, adding the corresponding amount of dilution water and shaking vigorously for 24 hours. The resulting solution was used as test solution without previous filtration.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain: Straus
- Source: Umweltbundesamt, Berlin
- Age of parental stock: between 0 and 24 hours old
- Feeding of the culture: with unicellular green algae (Desmodesmus subspicatus)
- Medium renewal of the culture: twice a week
- Feeding during the test: no

ACCLIMATION
- In-house bred is used. The breeding conditions are equivalent to the test conditions, therefore, no acclimation period was needed.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Remarks on exposure duration:

Observation of the mobility of the daphnids were made after 24 and 48 h exposure.

Hardness:

2.502 mmol/L or 250 mg CaCO3/L

Test temperature:

18.0 - 19.7 °C

pH:

7.6 - 7.7

Dissolved oxygen:

9.4 - 9.6 mg/L

Nominal and measured concentrations:

One treatment of 100 mg/L (nominal concentration)
No measured concentrations

Details on test conditions:

TEST SYSTEM
- Test vessel: glass beakers, nominal volume 50 mL
- Aeration: no
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: dionised water with enrichment of certain minerals
- CaCl2 * 2H2O: 293.8 mg/L
- MgSO4 * 7H2O: 123.3 mg/L
- NaHCO3: 64.8 mg/L
- KCl: 2.8 mg/L
- Culture medium different from test medium: yes, M4 Medium (recipe of Elendt) used for the culture
- Adjustment of the pH of the dilution water: yes, to 7.8 ± 0.2

OTHER TEST CONDITIONS
- Adjustment of pH of the stock solution: no
- Photoperiod of the culture: 16h light, 8 h dark, using neon tubes
- Light during the study: none

Reference substance (positive control):

yes

Remarks:

Potassium dichromate K2Cr2O7

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- No immobile daphnids were observed in the control or the treatment group during the 48-h exposure period.
- No abnormal behaviour or appearance of the animals was observed.

Results with reference substance (positive control):

The EC50 of the reference substance was determined to be 1.7 mg/L (95 % CI: 1.2 - 2.5 mg/L) after 24 h. The 24-h NOEC was determined as 0.625 mg/L.

Analytical Determinations

The measured DOC-values of the control and the treatment both lay below the limit of quantification, due to the very low solubility in medium. As no quantification of the test item in the treatments was possible, the biological results were based on the nominal concentration.

Validity

- The 24h-EC50 of the reference substance should lie between 0.6 and 1.7 mg/L. The 24h-EC50 of K2Cr207 was determined as 1.7 mg/L.

- Immobilisation in the controls may not exceed 10 %. Immobilisation in the controls was 0 %.

- The concentration of dissolved oxygen at the end of the test must be at least 3 mg/L. The lowest concentration of dissolved oxygen at the end of the test was 9.4 mg/L.

- The pH-value in the test solutions should not vary more than 1 unit during the test. The highest variation was 0.1 units.

Results

All validity criteria were met. For the estimation of the EC50 of the positive control, the fit showed sufficient statistical correspondence of the data with the dose-response equation. The 24h-EC50 of potassium dichromate was determined as 1.7 mg/L, lying within the demanded range of 0.6 - 1.7 mg/L. In the main study, the treatment snowed no toxicity. None of the animals were immobilised in the control. Because of the poor solubility in water, the analytical determinations of the test item showed weak correlation between nominal and measured concentrations. The measured DOC values in the test solution and in the control were below the limit of quantification. Therefore, the determination of the results was based on the nominal concentrations. The result of the test can be considered valid.

Validity criteria fulfilled:

yes

Conclusions:

The 48-h EC50 was determined to be >100 mg/L. No immobile daphnids were obsereved in the control and treatment groups.

Executive summary:

The acute toxicity of the test item to Daphnia magna was determined according to the OECD Guideline 202 and EU Council Regulation No. 440/2008 method C.2. A static test was performed as a limit test with a concentration of 100 mg/L. The test item solution was prepared as water-accomodation fraction solution. The test item was dissolved in dilution water - deionised water enriched with minerals. Five test animals were exposed to the test concentration and the control, respectively, for 48 hours. Analyses of dissolved organic carbon (DOC) were made by TC/IC measurement usind carbon analyser. The measured DOC-values of the blank controls and the treatment both lay below the limit of quantification due to the very low solubility in medium, threfore, the biological results were based on the nominal concentrations. No abnormal behaviour and mortality were observed in the treatment and the control group. In conclusion, the NOEC was determined to be >=100 mg/L. The EC50 and the EC100 corresponded to the nominal concentration >100 mg/L.

Reference 3

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

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

Adequacy of study:

weight of evidence

Justification for type of information:

Please refer to section 13 for "Read-Across justification".

Reason / purpose for cross-reference:

read-across source

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

740 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

1 340 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Reference 4

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

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

Adequacy of study:

weight of evidence

Justification for type of information:

Please refer to section 13 for "Read-Across justification".

Reason / purpose for cross-reference:

read-across source

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Description of key information

Based on a weight of evidence approach using two read-across studies, the acute toxicity to Daphnia as EC50 was determined to be 1340 mg/L and the NOEC to be 100 mg/L, respectively.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

1 340 mg/L

Additional information

No data on the substance itself is available. The test substance is a mixture of C12 and C18 chain phosphoric acid esters. Therefore, read-across approach to the C18 phosphoric acid ester was applied. Two read across studies are available assessing the short-term toxicity to aquatic invertebrates, Daphnia magna, of 1-Octanol, phosphate, potassium salt (CAS 68987-29-1). The available studies with C18 were used in a weight of evidence approach.

 

The first study was performed to assess the acute toxicity of CAS 68987-29-1 to Daphnia magna following a method designed to be compatible with the OECD Guidelines for Testing of Chemicals No 202, "Daphnia sp, Acute Immobilisation Test" referenced as Method C.2 of Commission Regulation (EC) No. 440/2008. Twenty daphnids per concentration (4 replicates of 5 animals) were exposed to the test item, at 6 nominal loading rates of 100, 1000, 1500, 2000, 2500, 5000 mg/L for 48 hours at a temperature of 21 to 22 °C under static test conditions. Immobilisation and any adverse reactions to exposure were recorded after 24 and 48 hours. The 48-Hour EC50 for the test item to Daphnia magna based on nominal concentration was 1340 mg/L. EC50 value was above the water solubility of CAS 68987-29-1.

 

In a second study, the acute toxicity of CAS 68987-29-1 to Daphnia magna was determined according to the OECD Guideline 202 and EU Council Regulation No. 440/2008 method C.2. A static test was performed as a limit test with a concentration of 100 mg/L. The test item solution was prepared as water-accomodation fraction solution. The test item was dissolved in dilution water - deionised water enriched with minerals. Five test animals were exposed to the test concentration and the control, respectively, for 48 hours. Analyses of dissolved organic carbon (DOC) were made by TC/IC measurement usind carbon analyser.The measured DOC-values of the blank controls and the treatment both lay below the limit of quantification due to the very low solubility in medium, threfore, the biological results were based on the nominal concentrations. No abnormal behaviour and mortality were observed in the treatment and the control group. In conclusion, the NOEC was determined to be >=100 mg/L. The EC50 and the EC100 corresponded to the nominal concentration >100 mg/L.

As no effects in both studies with Daphnia magna were observed up to the limit concentration of 100 mg/L, it can be concluded that the test substance itself has no effect on Daphnia magna up until 100 mg/L. Thus, the EC50 is determined as 1340 mg/L and the NOEC as 100 mg/L, as determined for CAS 68987-29-1, respectively.