2,3-dihydro-1,4-dihydroxyanthraquinone

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

other information

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Purity: 95.6 %

Analytical monitoring:

yes

Details on sampling:

Sampling schedule:
-Control: at 24 and 48 hours
-Test concentrations: at 24 and 48 hours

Vehicle:

no

Details on test solutions:

I. Pre-treatment of test item and preparation of test item concentration:
A stock solution was prepared to give the desired series of test concentrations. 99.8 mg of Dihydrochinizarion were added to 1 litre of dilution water on 2017-03-27 and 99.7 mg of the test item were added to 1 litre of dilution water on 2017-03-28, treated for 1 h in an ultrasonic bath and stirred for 24 h on a magnetic stirrer. Undissolved particles of the test item were removed by filtration using a folded filter with a pore size of 7 - 12 μm. The pH was measured to be 7.7 on 2017-03-28 and 7.8 on 2017-03-29.
To produce the different test item concentrations appropriate amounts of the stock solution were diluted with dilution water to a volume of 500 mL. 50 mL of the prepared solutions were taken per replicate and 0.5 mL of dilution water containing 5 daphnids was given to all replicates resulting in the final nominal concentrations. For each Dihydrochinizarion concentration and the control 4 replicates were prepared.

II. Culture and dilution water:
Reconstituted water (so-called 'M4 medium' according to OECD 202 and EC Method C.2, annex 1) was used for the maintenance of the test animals and the preparation of stock and test solutions of the test item.

Test organisms (species):

Daphnia magna

Details on test organisms:

Name: Daphnia magna STRAUS, parthenogenetic females
Source: Strain of Bundesgesundheitsamt Berlin
Maintenance and Acclimatisation: A population of parthenogenetic females of synchronized age structure has been maintained for more than 20 years in the test facility under constant temperature conditions (20 +/- 2 °C) at a 16 : 8 hour light-dark photoperiod (light intensity: < 20 μE x m-2 x s-1). The culture water (so-called 'M4 medium') was partly renewed once a week. The Daphnia were exclusively fed unicellular green algae (Desmodesmus subspicatus) 'ad libitum'. Mortalities of parent Daphnia during the culture period were recorded daily. The neonates were separated from their parent Daphnia by filtration prior to the acute test.

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

15.0 °dH (=268 mg/L CaCO3)

Test temperature:

18-22 °C

pH:

7.8-8.0

Dissolved oxygen:

8.2-8.8 mg/L (96-101 %)

Salinity:

n.a.

Conductivity:

n.a.

Nominal and measured concentrations:

nominal concentrations: 1.56, 3.13, 6.25, 12.5, 25, 50, 100 mg/L

Details on test conditions:

Exposure conditions:
-Test vessel: 100 mL glass beakers covered with watch glasses holding 5 neonates in 50 mL of test medium
-Experimental design:
-7 test concentrations plus 1 control
-5 neonates per vessel, 4 replicates per concentration/control
-no feeding during the exposure period
-semi-static system
-Method of initiation: Neonates were placed in prepare media
-Photoperiod: 16 h light : 8 h dark
-Temperature of incubation unit: 19.4 to 19.6 °C
-Aeration: none
-Test item concentrations: 1.56, 3.13, 6.25, 12.5, 25, 50 and 100 mg/L
-Method of administration: stock solution
-Medium renewal: daily
-Duration of exposure: 48 hours
-Criteria of effects: The criterion of adverse effects used in this study was the item-induced alteration of the normal mobility behaviour and the loss of locomotory actions of the neonates, observed at 24 and 48 hours.

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

0.087 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

0.441 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

0.042 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

EC0

Effect conc.:

0.06 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

EC100

Effect conc.:

> 0.39 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

0.207 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Validity criteria fulfilled:

yes

Remarks:

immobilisation and other abnormalities in the controls did not exceed 10% by the end of the test; dissolved oxygen concentration remained above 3 mg/L throughout the exposure period

Conclusions:

Acute toxicity to daphnia (daphnia magna) was tested in a semi-static test. After 24 hours an EC50 of 0.207 mg/L and after 48 hours an EC50 of 0.087 mg/L were determined. The results are expressed in terms of geometric mean measured concentrations.

Executive summary:

The study was performed to assess the acute toxicity of Dihydrochinizarin to Daphnia magna STRAUS under semi-static conditions. The study was conducted in accordance with the Council Regulation (EC) No 440/2008, Method C.2 ‘Acute toxicity for Daphnia’ (2008) which is equivalent to OECD Guideline for Testing of Chemicals No. 202 'Daphnia sp., Acute Immobilisation Test' (adopted April 13, 2004).

The Daphnia were exposed to a range of concentrations, nominally 1.56, 3.13, 6.25, 12.5, 25, 50 and 100 mg/L of Dihydrochinizarin dissolved in dilution water. Auxiliaries used to prepare the test media were an ultrasonic bath, a magnetic stirrer and a folded filter. Observations were made on the swimming ability and the immobilisation rate, respectively, after 24 and 48 hours of exposure. The test was conducted as a semi-static test with daily renewal of test medium. During the test a temperature range of 18 - 22 °C was maintained in the test vessels, with a maximum temperature fluctuation of +/- 1 °C in each individual test. The temperature, the pH and the oxygen values were measured every day in the freshly prepared media and in the media after 24 hours of exposure.

The following values were determined: 24-hr EC50=0.207 mg/L, 48hr-EC50=0.087 mg/L. The results are expressed in terms of geometric mean measured concentrations. Effective concentrations ranged from 0.5 % to 2.6 % in the freshly prepared media and from 0.18 % to 3.0 % in the media after 24 hours of exposure. The hardness of the dilution water used was 15.0 °dH (= 268 mg/L CaCO3). This toxicity study is classified as acceptable and satisfies the guideline requirements for the acute daphnia study.

Description of key information

Acute toxicity to daphnia (daphnia magna) was tested in a semi-static test. After  24 hours an EC50 of 0.207 mg/L and after 48 hours an EC50 of 0.087 mg/L were determined. The results are expressed in terms of geometric mean measured concentrations. Study was conducted according to OECD Guideline for Testing of Chemicals No. 202.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.087 mg/L