Ethyl 3,4-dihydroxybenzoate

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:

17 June 2016 to 25 July 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2016

Report date:

2016

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Ethyl 3,4-dihydroxybenzoate

EC Number:

223-529-0

EC Name:

Ethyl 3,4-dihydroxybenzoate

Cas Number:

3943-89-3

Molecular formula:

C9H10O4

IUPAC Name:

ethyl 3,4-dihydroxybenzoate

Test material form:

solid: particulate/powder

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Pre test/range finding
- Concentrations: 0.1 and 10 mg/L at 0 and 48 hours
- Sampling method: single 2.4 mL samples (pooled at 48 hours)
- Sample storage conditions before analysis: stored in freezer
Main study
- Concentrations: 0, 1.0, 1.8, 3.2, 5.6 and 10 mg/L at 0 and 48 hours
- Sampling method: single 2.4 mL samples (pooled at 48 hours)
- Sample storage conditions before analysis: stored in freezer

Reserve samples were taken but not used.

Test solutions

Vehicle:

no

Remarks:

test substance completely soluble in medium

Details on test solutions:

Starting with a concentration of 100 mg/L. Magnetic stirring for 1 hour (comb. limit/range-finding) or 1⅓ hour in combination with a 15-minute treatment with ultrasonic waves (final test) resulted in a completely dissolved solution. The lower test concentrations were prepared by subsequent dilutions of the 100 mg/L solution in test medium. All final test solutions were clear and colourless.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna (Crustacea, Cladocera)
- Strain/clone: Straus 1820
- Age: <24 h
- Source: In-house laboratory culture
- Age of parental stock: 4 weeks ( 2nd to 5th brood)
- Feeding during test: none
Breeding
- Feed : algae suspension
- Feeding frequency: daily

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

180 mg/L expressed as CaCO3

Test temperature:

20-21 °C

pH:

7.6-8.1

Dissolved oxygen:

8.5-9.0 mg/L

Salinity:

NA

Conductivity:

NA

Nominal and measured concentrations:

nominal : 0, 1.0, 1.8, 3.2, 5.6 and 10 mg/L
measured: 86-104% of nominal

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 mL
- Type (delete if not applicable): open
- Material: glass
- Aeration: none
- 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: ISO medium (M7, as prescribed by Dr. Elendt-Schneider)

OTHER TEST CONDITIONS
- Adjustment of pH: none
- Photoperiod: test performed in dark

EFFECT PARAMETERS MEASURED : mortality (immobility)

VEHICLE CONTROL PERFORMED: no, medium control included

RANGE-FINDING STUDY
- Test concentrations: 0, 0.1 1.0, 10 and 100 mg/L
- Results used to determine the conditions for the definitive study: immobilisation after 48h : 0, 0, 0, 100 and 100 % at Control, 0.10, 1.0, 10 and100 mg/L

Reference substance (positive control):

yes

Results and discussion

Effect concentrations

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

5.2 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mobility

Details on results:

Statistical method used to calculate EC50 values: Probit

Results with reference substance (positive control):

Potassium Dichromate 48 h EC50 0.39 mg/L (95% CI 0.33-0,44 mg/L)

Any other information on results incl. tables

Number of introduced daphnids and incidence of immobility in the final test

Time (h)	Replicate	Nominal concentration CH02700 (mg/L)
		Control	1.0	1.8	3.2	5.6	10
0	A	4*	5	5	5	5	5
	B	5	5	5	5	5	5
	C	5	5	5	5	5	5
	D	5	5	5	5	5	5
	Total introduced	19	20	20	20	20	20
24	A	0	0	0	0	0	3
	B	0	0	0	0	0	4
	C	0	0	0	0	0	1
	D	0	0	0	0	0	0
	Total immobilised	0	0	0	0	0	8
	Effect %	0	0	0	0	0	40
48	A	0	0	0	0	1	5
	B	0	0	0	0	5	5
	C	0	0	0	0	5	5
	D	0	0	0	0	5	5
	Total immobilised	0	0	0	0	16	20
	Effect %	0	0	0	0	80	100

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The EC50 in daphnia is 5.2 mg/L

Executive summary:

Daphnids (20/concentration) were exposed to the substance during 48 hours in a static test at 0, 1.0, 1.8, 3.2, 5.6 and 10 mg/L. At 5.6 and 10 mg/L the number of immobilised daphnids was 16 and 20 respectively. The 48 -h EC50 was calculated to be 5.2 mg/L.