1,2-Benzenediol, 4-(2-hydroxyethyl)-

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:

7th April 2020 to 28th April 2020

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2020

Report date:

2020

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes

Test material

Test material information

1

Reference substance name:

4-(2-hydroxyethyl)benzene-1,2-diol

EC Number:

600-704-3

Cas Number:

10597-60-1

Molecular formula:

C8H10O3

IUPAC Name:

4-(2-hydroxyethyl)benzene-1,2-diol

Sampling and analysis

Analytical monitoring:

yes

Remarks:

HPLC-UV

Details on sampling:

Analysis frequency: in 0-hour fresh solution and 48-hour old solution

Test solutions

Vehicle:

no

Details on test solutions:

Method of preparation of stock solution:
Range Finding Test
A solution at 1000 mg/L of the test item was prepared in culture medium. Then 5 different concentrations were prepared, with ten-fold dilutions from 1000 mg/L to 0.01 mg/L.

Definitive Test
Method of preparation of test solutions:
After the range finding test a solution at 1000 mg/L of the test item has been prepared in culture medium. Then 5 dilutions have been performed in culture medium in order to obtain the diluted nominal solutions 1.25, 2.50, 5.0, 10.0 and 20.0 mg/L.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain/clone: straus
- Age at study initiation: 6-24 hours
- Source: Breeder in Eurofins Biolab Test Facility
- Feeding during test: None

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Post exposure observation period:

24hr, 48 hr

Test conditions

Hardness:

between 140 and 250 mg CaCO3/L

Test temperature:

20°C ± 2°C

Dissolved oxygen:

>3 mg/L

Nominal and measured concentrations:

Based on a preliminary test, the test concentrations were used as follows:

Nominal amount of test item A solution of 1000 mg/L was prepared in culture medium.
Then five nominal concentrations were prepared 1.25, 2.5, 5.0, 10.0 and 20.0 mg/L.

Measured concentrations: the determined concentrations in fresh media were 1.18, 2.41, 4.79, 9.55 and 19.28 mg/L. The determined concentrations in 48 hours old media were 0.00, 0.00, 0.67, 1.61 and 4.64 mg/L.

The sample is considered not stable because the measured concentration of the test item at the end of the test has not been maintained within + 20% to the concentration at the measured concentrations at the beginning of the test.

Details on test conditions:

TEST SYSTEM
- 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: reconstituted water has been used; it has been prepared dissolving the following salts in 1 litre of deionised water: bihydrated calcium chloride 11.76 g/L, eptahydrated magnesium sulphate 4.93 g/L, acid sodium bicarbonate 2.59 g/l and potassium chloride 0.23 g/L.

OTHER TEST CONDITIONS
- pH: 7.60 - 8.06
- Photoperiod: test carried out in darkness

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

10.749 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

The sample is considered not stable because the measured concentration of the test item at the end of the test has not been maintained within + 20 %to the concentration at the measured concentrations at the beginning of the test.

As the test item was not stable the statistical analysis (EC50) has been performed using the measured concentrations at T=0.

There were no immobilised daphnia in any of the control replicates

Reported statistics and error estimates:

The EC50 was evaluated using EPA Probit Analysis Program Version 1.5.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The obtained results, in compliance with assay validity criteria, showed that Daphnia magna EC50 after 48 hours of the measured beginning concentration of the test item HYDROXYTYROSOL is equal to 10.749 mg/L.

Executive summary:

The aim of the study is to determine the ecotoxicological effects of the test item “HYDROXYTYROSOL”on biotic systems: in particular the aquatic organism Daphnia magna was used as test system in order to calculate the EC₅₀ value.
The toxicity of the test item, HYDROXYTYROSOL, on the cladocero Daphnia magna was evaluated according to OECD guideline No. 202.
After a range finding test, the organisms were exposed to various dilutions of the test item for a total period of 48 hours.
Daphnia were kept under observation for a period of 48 hours and the number of immobilised organisms and/or possible abnormal behaviours both in the control and in the treatment group vessel were observed.
At the beginning and at the end of the test (48 hours) dissolved oxygen and pH were measured in the highest concentration and in the control group. The temperature of the assay environment was recorded at the beginning and at the end of the test.
The stability of the test item in the definitive test was performed using HPLC equipped with a UV detector according to method described in STULV20AA0627-1 GLP - MdP.
The test item was measured at the beginning and at the end of the test in the control and in the treated samples.
The obtained results, in compliance with test acceptability criteria, of the nominal concentration of the test item can be summarised as follow:
EC₅₀ of the test item at T= 48 h (measured concentration at the beginning of the test) = 10.749 mg/L