Tri-2-propyn-1-yl phosphate

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2021

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2021

Report date:

2021

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

OECD Guideline for Testing of Chemicals No. 202, adopted 13. Apr. 2004

Deviations:

yes

Remarks:

The temperature in the experiment was in the range 19.8 – 23.2 °C

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

Commission Regulation (EC) No. 440/2008, Method C.2. “Daphnia sp. Acute Immo-bilisation Test”, adopted 30. May 2008

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

tris(prop-2-yn-1-yl) phosphate

EC Number:

853-966-8

Cas Number:

1779-34-6

Molecular formula:

C9H9O4P

IUPAC Name:

tris(prop-2-yn-1-yl) phosphate

Specific details on test material used for the study:

Test Item: Phosphoric acid,tri-2-propargyl ester
Lot No.: H219121101
CAS No.: 1779-34-6
EINECS-No.: 853-966-8
Molecular Formula: C9H9O4P
Molecular Weight: 212 g/mol
Purity: 99%
Appearance: Yellow liquid
Homogeneity: Homogenous

Sampling and analysis

Analytical monitoring:

not specified

Details on sampling:

- Sample Preparation:
Before the measurement at the start and the end of the test, 500 µL of the taken sample from the concentrations 22 mg/L were diluted with 500 µL M4-medium (2-fold), 200 µL of the taken sample from the concentrations 46 mg/L were diluted with 800 µL M4-medium (5-fold) and 100 µL of the taken sample from the concentrations 100 mg/L were diluted with 900 µL algal medium and 100 µL (10-fold).

Test solutions

Vehicle:

no

Details on test solutions:

- Preparation: A stock solution containing 100.0 mg/L (corresponds to 83.6 µL/L based on a density of 1.196 g/cm3 at 20 °C given by the sponsor) test item in M4-medium was prepared.
The lower treatments (4.6 / 10 / 22 / 46 mg/L nominal) were prepared by dilution of this stock solution with M4-medium.

- Positive Control: Potassium dichromate K2Cr2O7 (CAS No. 7778-50-9) was used as positive control in a current reference study (202105R201). The 24h-EC50 value was determined as 2.22 mg/L.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

- Specification
Species: Daphnia magna
Authority: STRAUS
Strain: Berlin
Sex: female
Age: between 0 and 24 hours
Origin: Umweltbundesamt Berlin
In-house breeding since: 27. September 2007

- Animal Husbandry
Daphnia magna is bred in the LAUS GmbH throughout the year. The animals are kept for the use in toxicity tests. They multiply by parthenogenesis, thus being genetically identi-cal. The keeping is performed similar to the method described in the OECD guideline, fol-lowing SOP 115 002 01 („Zucht und Hälterung von Daphnia magna STRAUS“), version 13 from 11. Nov. 2019.
Vessels: preserving glasses, nominal volume 2 L
Medium: M4-Medium (recipe of ELENDT)
Food: green algae (Desmodesmus subspicatus)
Medium renewal: twice a week
Photo period: 16/8 hours, using neon LED’s
Temperature: 20 +-2 °C

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Test temperature:

19.8 – 23.2 °C

pH:

7.5 - 7.6 (test start)
7.3 - 7.5 (test end)

Dissolved oxygen:

8.7 - 9.2 (O2-Concentration in mg/L) (test start)
8.5 - 8.6 (O2-Concentration in mg/L) (test end)

Nominal and measured concentrations:

nominal concentration: 4.6, 10, 22, 46 and 100 mg/L
measured concentration: 4.9, 10.49, 22.01, 47.32 and 102.8 mg/L

Details on test conditions:

EXPERIMENTAL CONDITIONS:
- Treatments: 4.6 / 10 / 22 / 46 / 100 mg/L (nominal concentration)
The concentrations to be tested are based on the result of a non-GLP pre-test.
- Temperature: 19.8 – 23.2 °C (see chapter 12 Deviations)
within one test, temperature did not vary more than 2 °C
- Photo period: 16/8 hours, using LED’s
- Duration: 48 hours
- Observation times: 24 and 48 hours
- Medium renewal: none
- Test vessels: glass beakers, nominal volume 50 mL, tall shape
- Replicates (Treatments): 4 vessels, each containing 20 ± 5 mL test solution and 5 daphnia
- Replicates (Blank control): 4 vessels, each containing 20 ± 5 mL M4-medium and 5 daphnia

TEST MEDIUM / WATER PARAMETERS
- Test medium: M4 MEDIUM
- Culture medium different from test medium: No
- Intervals of water quality measurement: The pH values and the concentration of dissolved oxygen measured at the start and the end of the test are stated.

VEHICLE CONTROL PERFORMED: no

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

ca. 22.22 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: immobility

Remarks on result:

other: 95%-confidence interval

Remarks:

18.21 mg/L – 26.90 mg/L

Effect concentrations 2

Key result

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

ca. 45.54 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: immobility

Remarks on result:

other: 95%-confidence interval

Remarks:

34.33 mg/L – 63.99 mg/L

Effect concentrations 3

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

ca. 10 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: immobility

Effect concentrations 4

Key result

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

ca. 22 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: immobility

Details on results:

The study was performed using 5 concentrations ranging from 4.6 to 100 mg/L nominal concentration. For each test concentration and the blank control, 20 daphnia were ex-posed to the test item for 48 hours in a static test system. After 24 and 48 hours, the im-mobilised daphnia were counted.
Three concentrations showed toxicity between 55 and 100 % immobilisation after 48 h. None of the animals was immobilised in the blank control.
Potassium dichromate K2Cr2O7 (CAS No. 7778-50-9) was used as positive control in a current reference study to assure that the test conditions are reliable. The values lay with-in the range of the laboratory (1.20 – 2.82 mg/L).

At the start and at the end of the test, the content of the test item in the test solutions was determined using HPLC.
The measured concentrations lay between 100 % and 107 % of the nominal concentra-tions at the beginning of the test and between 113 % and 117 % of the nominal concen-trations at the end of the test. Therefore, the determination of the results was based on the nominal concentrations (see OECD guidance document No. 23 (§ 176)).

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the study, the 48 hour EC50 of the test material was determined to be 22.22 mg/l.

Executive summary:

In this guideline (OECD 202) study conducted with GLP certification, the objective of this study was to evaluate the toxicity of the test item Tri-2-propyn-1-yl phosphate (LDY196) in an acute immobilisation test under static conditions towards Daphnia magna. Daphnia magna STRAUS, was chosen in the guideline as a typical species of zoo-plankton. A non GLP pre-test was conducted to find the concentrations to be tested. Based on the results of the pre-test, a definitive test was carried out with the following concentrations of test substance: 0 (control); 4.6, 10, 22, 46 and 100 mg/L. For each test concentration and the blank control, 20 daphnia were exposed to the test item for 48 hours in a static test system. After 24 and 48 hours, the immobilised daphnia were counted. The 48-hours EC50 value was 22.22 mg/L and the 24-hours EC50 value was 45.54 mg/L. The highest test substance concentration which no observed significant adverse effect (NOEC) on algal growth was 10.00 mg/L and the lowest test substance concentration at which was observed significant reducing effect on growth (LOEC) was 22.00 mg/L.