3-[(phenylcarbamoyl)amino]phenyl 4-methylbenzenesulfonate

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:

22 May 2019 - 24 May 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

13 April 2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Identification and stability of the test material under storage conditions: The infrared (IR) spectrum of the test material measured at the test facility was confirmed to be identical to that provided by the sponsor. In addition, the IR spectrum of the test sample after the completion of the experiment was the same as that before the start of the experiment, and it indicated that the test material was stable under storage conditions.

The purity of the test material was treated as 100%

Analytical monitoring:

yes

Remarks:

HPLC

Details on sampling:

- The concentration of the test material in the test solution was measured at the start and end of exposure.
- Sample for measurement:
1) Another solution sampled separately from the preparation container (at the start of exposure).
2) The mixed solution taken out with equal volume from the middle layer of the test solution in the test vessels in each test level (at the end of exposure).
- Volume of sample: Approximately 10 mL for all test levels.

Vehicle:

yes

Remarks:

Dilution water

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- The test material (0.100 g) and dilution water (1000 mL) were mixed to prepare the nominal concentration of 100 mg/L, and were stirred for 48 hours at about 20 °C.
- The suspension was filtered with a membrane filter (GV, 0.22 μm pore size, Merck) by suction.
- The filtrate was stirred for 30 minutes at about 20 °C to recover dissolved oxygen concentration decreased at the suction filtration to prepare the test solution, which was divided into each test vessel.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain/clone: Clone A
- Age at study initiation: less than 24-hour-old
- Age of parental stock: 27-day-old
- No feeding during test.

ACCLIMATION
- Young daphnids produced by parents that were cultured in the test facility were used. The parents to obtain young daphnids were bred in the same quality of water, water temperature and photoperiod as used in the study. The parents animals used for the test were from the same lot.
- Food type: Chlorella vulgaris of 0.1 - 0.2 mgC (Organic carbon content)/day per Daphnia was fed to the parents once a day.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Post exposure observation period:

Observations were conducted at 24 and 48 hours after exposure.

Hardness:

42 mg/L

Test temperature:

20.0 - 20.1 °C

pH:

7.7 - 7.8

Dissolved oxygen:

8.7 - 8.8

Conductivity:

17 mS/m

Nominal and measured concentrations:

Nominal: 100 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 mL glass beaker
- Fill volume: 100 mL
- Type: closed with transparent plastic lid
- Water bath: plastic tank with warming/cooling unit (Type HCA 250, Sato craft)
- Aeration: No
- Renewal rate of test solution (frequency/flow rate): No renewal
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per vehicle control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Dechlorinated tap water, aerated sufficiently
- Total organic carbon: < 0.05 mg/L
- Suspended solid: < 1 mg/L
- Chlorine: below 0.02 mg/L
- Alkalinity: 41 mg/L
- Conductivity: 17 mS/m
- Culture medium different from test medium: No

OTHER TEST CONDITIONS
- Adjustment of pH: No
- Photoperiod: 16 hours light / 8 hours dark

EFFECT PARAMETERS MEASURED
- Observation of test organisms at 24 and 48 hours after exposure. Daphnids were considered immobile when they were not able to swim within 15 seconds after gentle agitation of the test vessel.
- The number of immobilised daphnids and the percentage immobility were recorded after 24 and 48 hours of exposure.
- The appearance of the test solution was observed at the start and end of exposure. Additionally, the dissolved oxygen concentration, pH and temperature were measured at the start and end of exposure.

EC50 CALCULATION
Since more than 50% immobility could not be obtained in the exposure level, the EC50 was estimated as > test concentration. The results of the study were estimated based on the time-weighted mean of the measured concentrations of the test solution during exposure as the test concentration.

RANGE-FINDING STUDY
- Test concentrations: nominal concentration of 100 mg/L, stock solution content of 10.0 %, 30.0 % and 100 % were measured.
- 10 daphnids per test level, (5 daphnids/test vessel) were used for the study.
- After 24 and 48 hours the immobility was 0 % at all concentrations and no other abnormal response was observed. The test concentration was therefore based at the level of the the solubility of the test material in dilution water.

VALIDITY OF THE TEST
- The immobilisation rate should not be more than 10 % in the control during exposure.
- Not more than 10 % of the control daphnids should show the signs of disease or stress, for example discolouration or unusual behaviour such as trapping at surface of water.
- Dissolved oxygen concentration should be more than 3 mg/L at the end of exposure.

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 0.016 mg/L

Nominal / measured:

meas. (TWA)

Conc. based on:

test mat.

Basis for effect:

mobility

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

IMMOBILITY
No immobility was obtained in the exposure level during exposure. Immobility in the control was 0 %, which met the criteria for the validity of the test (i.e. not more than 10 %).

OBSERVED ABNORMAL RESPONSE
In the exposure level, neither immobilisation nor abnormalities of behaviour nor appearance were observed.
The in the control, no abnormal response (discolouration of body, trapping at surface of the water) was observed which met the criterion for the validity of the test (i.e. not more than 10 %).

OBSERVATION AND MEASUREMENT OF TEST SOLUTION
- Appearance: The test solutions in the exposure level and the control were colourless and clear at the start and at the end of exposure.
- Condition of test solution: dissolved oxygen concentration, pH and temperature were 8.7 - 8.8 mg/L, 7.7 - 7.8 and 20.0 - 20.1 °C respectively. The measured values of dissolved oxygen concentration met the criterion for the validity of the test.

Results with reference substance (positive control):

The positive control study was conducted from 16 to 18 April 2019. The 48-hour EC50 was determined to be 0.22 mg/L. This value was within the stipulated range (mean ± 2 S.D.: 0.097 - 0.35 mg/L, n=105) to background data at the Test Facility.

Reported statistics and error estimates:

24 hour LC50: > 0.0157 mg/L, 48 hour LC50: > 0.0157 mg/L

Overall results of immobility

Measured concentration (mg/L)*	Vessel	24 hours		48 hours
		Number of immobilised daphnids/ total daphnids	Immobility (%)	Number of immobilised daphnids/ total daphnids	Immobility (%)
Control	A	0 / 5	0	0 / 5	0
	B	0 / 5		0 / 5
	C	0 / 5		0 / 5
	D	0 / 5		0 / 5
0.0157	A	0 / 5	0	0 / 5	0
	B	0 / 5		0 / 5
	C	0 / 5		0 / 5
	D	0 / 5		0 / 5

* The time-weighted mean of measured concentrations

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of this study the 48 hour EC50 of the test material was determined to be > 0.0157 mg/L (measured, TWA) and > 100 mg/L (nominal).

Executive summary:

The short-term toxicity of the test material to Daphnia magma was investigated through an immobilisation study which was conducted in accordance with the standardised guidelines OECD 202, and under GLP conditions. 

This study was conducted as a limit test in order to confirm the effect of the test material on the test organisms at around the solubility of the test material in dilution water. As a result, no immbolity was found in the definitive study. Therefore, it was decided that the test material had no remarkable effect on the test organisms at around the solubility in dilution water. The concentration of the test material in the test solution during exposure was maintained at that of the start of the exposure. The environmental conditions were within a suitable range. Therefore, it is concluded that this study complied with the applied test guidelines. 

Under the conditions of this study the 48 hour EC50 of the test material was determined to be > 0.0157 mg/L (measured, TWA) and > 100 mg/L (nominal).

Description of key information

The 48 hour EC50 of the test material was determined to be > 0.0157 mg/L (measured, TWA) and > 100 mg/L (nominal).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

LC50

Effect concentration:

> 0.016 mg/L

Additional information

The short-term toxicity of the test material to Daphnia magma was investigated through an immobilisation study which was conducted in accordance with the standardised guidelines OECD 202, and under GLP conditions. The study was awarded a reliability score of 1 in accordance with the criteria set forth by Klimisch et al. (1997).

This study was conducted as a limit test in order to confirm the effect of the test material on the test organisms at around the solubility of the test material in dilution water. As a result, no immobility was found in the definitive study. Therefore, it was decided that the test material had no remarkable effect on the test organisms at around the solubility in dilution water. The concentration of the test material in the test solution during exposure was maintained at that of the start of the exposure. The environmental conditions were within a suitable range. Therefore, it is concluded that this study complied with the applied test guidelines. 

Under the conditions of this study the 48 hour EC50 of the test material was determined to be > 0.0157 mg/L (measured, TWA) and > 100 mg/L (nominal).