Sodium hydrogen m-sulphonatobenzoate

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:

key study

Study period:

2019

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)

Version / remarks:

adopted 30. May 2008

Deviations:

yes

Remarks:

Details on devistions from EU Method C.2 have been reported in section "Any other information on materials and methods incl. tables".

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

adopted 13. Apr. 2004: ”Daphnia sp., Acute Immobilisation Test“.

Deviations:

yes

Remarks:

Details on devistions from OECD Guideline 202 have been reported in section "Any other information on materials and methods incl. tables".

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Batch no.: 170103
Appearance: White crystalline powder
CAS No.: 17625-03-5
EINECS-No.: 241-602-5
Molecular formula: C7H5SO5Na
Molecular weight: 224.17 g/mol
Purity: > 99.0% (Titration with NaOH, Glass indicating electrode, Calomel reference electrode)
Homogeneity: totally homogeneous
Stability: H2O: 96h; EtOH: unknown; acetone: unknown; CH3CN: unknown; DMSO: unknown
Solubility: H2O: >1 g/L; EtOH: unknown; acetone: unknown; CH3CN: unknown; DMSO: unknown
Production date: 2017
Expiry date: 14. Feb. 2024
Storage: Room Temperature (20 ± 5°C), keep away from humidity

Analytical monitoring:

yes

Details on sampling:

Preparation
A stock solution containing 99.8 mg/L test item in dilution water was prepared. For homogenisation, an ultrasonic bath was used. The lower concentrations were prepared by dilution of this stock solution with dilution water.

Vehicle:

yes

Remarks:

water

Details on test solutions:

A stock solution containing 99.8 mg/L test item in dilution water was prepared. For homogenisation, an ultrasonic bath was used. The lower concentrations were prepared by dilution of this stock solution with dilution water.

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.
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 dilution water and 5 daphnia.

Test organisms (species):

Daphnia magna

Details on test organisms:

Species: Daphnia magna
Authority: STRAUS
Strain: Berlin
Sex: female
Age: between 0 and 24 hours
Origin: Umweltbundesamt Berlin
Selection of the test system was made following the proposal of the guidelines.

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 identical. The keeping is performed similar to the method described in the OECD guideline, following 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 tubes
Temperature: 20 +/- 2 °C

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

Please, see section "salinity".

Test temperature:

The temperature in the experiment was in the range of 19.1 – 21.2 °C and; therefore, fluctuated by more than ± 1 °C. As all validity criteria were met and no immobility in the blank control was occurred, this was stated as uncritical.

pH:

Blank control; pH = 7.6 (0 h); pH = 7.9 (48 h)
Nominal Concentration (mg/L) = 4.6; pH = 7.6 (0 h); pH = 7.9 (48 h)
Nominal Concentration (mg/L) = 10; pH = 7.5 (0 h); pH = 7.9 (48 h)
Nominal Concentration (mg/L) = 22; pH = 7.4 (0 h); pH = 7.9 (48 h)
Nominal Concentration (mg/L) = 46; pH = 7.3 (0 h); pH = 7.8 (48 h)
Nominal Concentration (mg/L) = 100; pH = 6.9 (0 h); pH = 7.8 (48 h)

Dissolved oxygen:

Blank control; O2 = 8.5 (0 h); O2 = 8.2 (48 h)
Nominal Concentration (mg/L) = 4.6; O2 = 8.5 (0 h); O2 = 8.4 (48 h)
Nominal Concentration (mg/L) = 10; O2 = 8.5 (0 h); O2 = 8.5 (48 h)
Nominal Concentration (mg/L) = 22; O2 = 8.6 (0 h); O2 = 8.5 (48 h)
Nominal Concentration (mg/L) = 46; O2 = 8.6 (0 h); O2 = 8.5 (48 h)
Nominal Concentration (mg/L) = 100; O2 = 8.6 (0 h); O2 = 8.4 (48 h)

Salinity:

Dilution water (Daphnia medium) with the following specification was used (stated in SOP 11800201)

Concentration in mg/L
CaCl2*2H2O = 293.80 mg/L
MgSO4*7H2O = 123.30 mg/L
NaHCO3 = 64.80 mg/L
KCl = 5.80 mg/L

Conductivity:

Not determined.

Nominal and measured concentrations:

Nominal Concentration Test Item (mg/L) = 4.6
Mean Measured Concentration t = 0 h (mg/L) = 4.55
Mean Measured Concentration t = 48 h (mg/L) = 4.97

Nominal Concentration Test Item (mg/L) = 10
Mean Measured Concentration t = 0 h (mg/L) = 10.11
Mean Measured Concentration t = 48 h (mg/L) = 10.85

Nominal Concentration Test Item (mg/L) = 22
Mean Measured Concentration t = 0 h (mg/L) = 22.24
Mean Measured Concentration t = 48 h (mg/L) = 24.51

Nominal Concentration Test Item (mg/L) = 46
Mean Measured Concentration t = 0 h (mg/L) = 45.91
Mean Measured Concentration t = 48 h (mg/L) = 51.60

Nominal Concentration Test Item (mg/L) = 100
Mean Measured Concentration t = 0 h (mg/L) = 100.17
Mean Measured Concentration t = 48 h (mg/L) = 110.17

Details on test 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 19.1 – 21.2 °C
Photo period 16/8 hours, using neon tubes
Duration 48 hours
Observation times at 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 dilution water and 5 daphnia

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

94.59 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95%-confidence interval = 76.81 - 136.18 mg/L

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

70.83 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95%-confidence interval = 58.84 - 85.53 mg/L

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

46 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

100 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

Further details on results are reported in section "Any other information on results incl. tables".

Immobility

In the blank control, one of the daphnia was immobilised. The two highest concentrations containing 46 mg/L and 100 mg/L showed toxicity between 15 and 85% immobilisation.(see table below):

Table. Immobility.

Nominal Concentration in mg/L	Immobility 24 hours					Immobility 48 hours
	absolute				in %	absolute				in %
Blank control	0	0	0	0	0	0	0	1	0	5
4.6	0	0	0	0	0	0	1	0	0	5
10	0	0	0	0	0	1	0	0	0	5
22	0	0	0	0	0	0	0	0	1	5
46	0	0	1	0	5	0	2	1	0	15
100	4	2	4	1	55	5	4	4	4	85

 

pH and O₂

The pH values and the concentration of dissolved oxygen in the test media and the blank control are given in the following table.

Table. pH and O₂-values.

Nominal Concentration in mg/L	pH		O2-Concentration in mg/L
	0 h	48 h	0 h	48 h
Blank control	7.6	7.9	8.5	8.2
4.6	7.6	7.9	8.5	8.4
10	7.5	7.9	8.5	8.5
22	7.4	7.9	8.6	8.5
46	7.3	7.8	8.6	8.5
100	6.9	7.8	8.6	8.4

 

Analytical Determinations

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 QC samples were measured in duplicate at the beginning and end of each sequence.

The measured concentrations lay between 99 % and 112 % of the nominal concentrations. Therefore, the determination of the results was based on the nominal concentrations (see OECD Guidance Doc. No.23).

The measured concentrations for treatment and blank control are given in the following tables.

Table. Raw Data and Measured Concentrations.

Nominal Concentration Test Item	Area  t = 0 h	Area  t = 48 h	Dilution Factor	Measured Concentration  t = 0 h	Measured Concentration  t = 48 h
mg/L				mg/L	mg/L
QC 10 mg/L	6.0378	5.8189	--	10.000	10.000
QC 10 mg/L	6.0167	5.7777	--	10.000	10.000
Blank control	n.a.	n.a.	--	0.00	0.00
Blank control	n.a.	n.a.	--	0.00	0.00
4.6	2.8690	2.8862	--	4.608	4.906
4.6	2.7926	2.9607	--	4.483	5.034
10	6.1080*	6.3426	--	9.873	10.853
10	6.1079	6.3419	--	9.873	10.852
22	6.8563	7.1405	2	22.180	24.452
22	6.8932	7.1763	2	22.300	24.575
46	10.0878*	5.9947	5	81.718	51.273
46	5.6804	6.0708	5	45.891	51.927
100	6.1695	6.4418	10	99.734	110.237
100	6.2229	6.4337	10	100.603	110.099
46	5.6902**	--	5	45.971	--
10	6.3973**	--	--	10.344	--
QC 10 mg/L	11.6296*	5.8392	--	10.000	10.000
QC 10 mg/L	6.2389	5.9513	--	10.000	10.000

n.a. not analysable

* Results not used, because interference signals

** Repetition of measurement due to interference signals

Table. Mean of Measured Concentrations and % of Nominal Concentration.

Nominal Concentration Test Item	Mean Measured Concentration  t = 0 h	Mean Measured Concentration  t = 48 h	% of Nominal t = 0 h	% of Nominal t = 48 h
mg/L	mg/L	mg/L	%	%
4.6	4.55	4.97	99	108
10	10.11	10.85	101	109
22	22.24	24.51	101	111
46	45.91	51.60	100	112
100	100.17	110.17	100	110

 

Validity criteria fulfilled:

yes

Conclusions:

Short-term toxicity of sodium 3-sulfobenzoate towards Daphnia magna has been determined according to EU C.2 Method and the following results were determined:
48h-NOEC = 46 mg/L
48h-LOEC = 100 mg/L
24h-EC50 = 94.59 mg/L
48h-EC50 = 70.83 mg/L

Executive summary:

Short-term toxicity of sodium 3-sulfobenzoate towards Daphnia magna has been determined according to EU C.2 Method. One valid experiment was performed. 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 exposed to the test item for 48 hours in a static test system. After 24 and 48 hours, the immobilised daphnia were counted.

The two highest concentrations containing 46 mg/L and 100 mg/L showed toxicity between 15 and 85% immobilisation. One of the animals was immobilised in the blank control. This 5% immobilisation can be neglected.

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 measured concentrations at the beginning and the end of the test lay between 99 % and 112 % of the nominal concentrations. Therefore, the determination of the results was based on the nominal concentrations (see OECD Guidance Doc. No.23).

The following results were determined for the test item sodium 3-sulfobenzoate:

48h-NOEC = 46 mg/L

48h-LOEC = 100 mg/L

24h-EC50 = 94.59 mg/L

48h-EC50 = 70.83 mg/L

Description of key information

Short-term toxicity of sodium 3-sulfobenzoate towards Daphnia magna has been determined according to EU C.2 Method. One valid experiment was performed. 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 exposed to the test item for 48 hours in a static test system. After 24 and 48 hours, the immobilised daphnia were counted.

The two highest concentrations containing 46 mg/L and 100 mg/L showed toxicity between 15 and 85% immobilisation. One of the animals was immobilised in the blank control. This 5% immobilisation can be neglected.

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 measured concentrations at the beginning and the end of the test lay between 99 % and 112 % of the nominal concentrations. Therefore, the determination of the results was based on the nominal concentrations (see OECD Guidance Doc. No.23).

The following results were determined for the test item sodium 3-sulfobenzoate:

48h-NOEC = 46 mg/L

48h-LOEC = 100 mg/L

24h-EC50 = 94.59 mg/L

48h-EC50 = 70.83 mg/L

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

70.83 mg/L