Phosphoric acid, C14-15-branched and linear alkyl esters, potassium salts

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2018

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

Limit test instead of full test - due to an error of the testing laboratory the effect concentration observed was below the lowest the effect concentration of other tested taxa - this finding was not reported to the sponsor. Test will be repeated.

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

yes

Remarks:

Limit test instead of full test - due to an error of the testing laboratory the effect concentration observed was below the lowest the effect concentration of other tested taxa - this finding was not reported to the sponsor. Test will be repeated.

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Name: Phosphoric acid, C14-15 branched and linear alkyl esters, potassium salts
CAS No.: 1893414-79-3
Physical state: white solid at 20 °C
Batch No.: PU61810016
Re-certification date of batch: 09 March 2018
Purity: 100 % (UVCB, lyophilized solid, water content 0.85 % (w/w))
Stability: stable under test conditions
Storage condition of test material: Room temperature, protected from light

Analytical monitoring:

yes

Details on sampling:

Analytical data are required by the guidelines for verification of test item concentrations as well as the stability of the test item over the entire test period. Analytical samples were taken in 24 h intervals from fresh and aged test solutions. For each sampling also a retain sample was taken. 500 µL samples were taken and stabilized with 500 µL methanol (MeOH). All samples were stored deep frozen until they were transferred to the analytical laboratory.

Vehicle:

no

Details on test solutions:

Based on the lowest EC50 value of existing and reliable algae or acute invertebrate toxicity data, the following nominal test item concentration was tested in the main test: 100, 45.5, 20.7, 9.39 und 4.27 mg/L and control (see description of deviations caused by testing laboratory above). The necessary amount of test item for preparing the stock solution S1 was weighed on a weighing scoop and transferred to a volumetric flask. Test medium was added up to the bench mark and the stock solution was homogenised by shaking. Afterwards the solution was slightly turbid milky and white flakes appeared. The stock solution S1 was then transferred to the test vessel. The preparation procedure was repeated every 24 hours.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

The species used for the test was Danio rerio Hamilton (Cypriniformes: Cyprinidae). This species is a recommended sensitive indicator species for testing the side effects of chemicals. Fish from the own stock breeding of the test facility were used. The parent animals were originally purchased from the Karlsruhe Institute of Technology (KIT, Karlsruhe, Germany) in a healthy condition. According to the supplier they had been bred from wild strain (WIK) zebrafish before. Since they have been purchased, the zebrafish were continuously reared in the laboratory of the testing facility. Only fish in good health and free from any apparent malformation were used. The last feeding was performed one day prior test start.

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

The holding water was composed of reconstituted test water consisting of analytical grade salts dissolved in purified water. The water parameters were controlled 3 times a week. The total hardness was between 140 - 250 mg/L (as CaCO3), corresponding to 7.8 - 14°dH.

Test temperature:

The water temperature was 21 to 25 °C.

pH:

The pH-value of the aerated water was between 6.0 - 8.5.

Dissolved oxygen:

For at least seven days prior to testing the dissolved oxygen was above 80 % saturation.

Salinity:

The holding water was composed of reconstituted test water consisting of analytical grade salts dissolved in purified water. The ratio of Ca:Mg and Na:K was 4:1 and 10:1, respectively, based on molarity. The water parameters were controlled 3 times a week.

Nominal and measured concentrations:

The content of the substance in test solutions was analytically determined to confirm the correct application of the test item. The measured content of the test item in fresh test solutions was between 16.5 % and 39.7 % of nominal. The measured content of the test item in aged test solutions was between 6.79 % and 45.3 % of nominal. Since the measured concentrations of the test item in all test item solutions were below 80 % of nominal concentrations, the biological endpoints were evaluated using the mean measured test item concentration. Using mean measured concentrations for study evaluation is an acceptable according to the Guideline OECD 203, when the start values are outside the range of 80 % and 120 %.

Details on test conditions:

Biological Assessment

Fish were observed at 0, 4, 24, 48, 72 and 96 hours after test start. Fish were considered dead if there was no visible movement (e.g. gill movement), and if touching of the caudal peduncle produced no reaction. Records were made on visible abnormalities as: loss of equilibrium, swimming behaviour, respiratory function, pigmentation and all other observed events. Dead fish were removed if observed and mortality, length and weight were recorded. At termination of the test, all remaining fish were euthanized and all fish were weighed and measured.

Physico-Chemical Assessments
Measurements of temperature, pH-value and oxygen saturation were performed in 24 hour intervals in fresh and aged test solutions. Water hardness of the untreated control was determined at the beginning of the test.

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (total fraction)

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

> 10 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Results with reference substance (positive control):

not specified

Reported statistics and error estimates:

not determined

Validity criteria fulfilled:

not applicable

Remarks:

see description below

Conclusions:

According to the results of the OECD 203 limit test, the LC50 (96 h) of the test item was determined to be > 23.4 mg/L based on nominal test item concentrations and > 6.32 mg/L based on mean measured concentrations. The corresponding NOEC (mortality) (96 h) was 23.4 mg/L based on nominal test item concentrations and 6.32 mg/l based on mean measured concentrations.

Executive summary:

According to the results of the OECD 203 limit test, the LC50 (96 h) of the test item was determined to be > 23.4 mg/L based on nominal test item concentrations and  > 6.32 mg/L based on mean measured concentrations. The corresponding NOEC (mortality) (96 h) was 23.4 mg/L based on nominal test item concentrations and 6.32 mg/l based on mean measured concentrations. No sublethal effects were observed in the control and at the threshold concentration of 23.4 mg/L (test item nominal) and 6.32 mg/L (test item mean measured) after 96 h. Since the measured concentration, 6.32 mg/L is below the measured concentration of the most sensitive organism Daphnia magna, 7.96 mg/L (Kümmich, F. 2017), the conclusion that fish is not the most sensitive organism is not possible.

Description of key information

According to the results of the OECD 203 limit test, the LC50 (96 h) of the test item was determined to be > 23.4 mg/L based on nominal test item concentrations and  > 6.32 mg/L based on mean measured concentrations. The corresponding NOEC (mortality) (96 h) was 23.4 mg/L based on nominal test item concentrations and 6.32 mg/l based on mean measured concentrations.