2-[[4-[ethyl(2-hydroxyethyl)amino]phenyl]azo]-6-methoxy-3-methylbenzothiazolium methyl sulphate

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

For details and justification of read-across please refer to the attached report in section 13 of IUCLID.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

ca. 0.17 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% confidence limit

Remarks:

ca. 0.14 - 0.19

Details on results:

Test evaluations were done according to the guidelines by visual assessment of the mobility of the daphnids after 24 and 48 hours.
The EC50 was calculated by using the Probit model and by graphical determination on logarithmic probability paper.
The concentration of the test substance at the beginning and at the end of the test was analysed by the analytical Service Klybeck.

The EC0 and the EC100 after 48 h of exposure was 0.08 mg/L and 0.45 mg/L, respectively.

Results with reference substance (positive control):

EC50 (24 h) = 0.9 ppm (range: 0.8 - 1.5 ppm)

1) Analytical results of test substance measurements:

Nominal concentration [ppm]	Concentration start [ppm]	Concentration end [ppm]	Mean value* [ppm]
0.10	0.08	0.07	0.08
0.18	0.14	0.13	0.14
0.32	0.26	0.23	0.25
0.58	0.47	0.42	0.45
1.00	0.80	0.75	0.78

* used for calculation of EC₅₀ value

2) Oxygen concentration and pH

The oxygen concentration and the pH was controlled at the beginning and at the end of the test.

Start:        - Oxygen: saturated

- pH: 8.0 (highest test concentration)

- Temp.: 21° C

End:

Nominal Conc. [ppm]	0.1	0.18	0.32	0.58	1.0	Blank
Oxygen [%]	96	96	96	97	96	97
pH	7.9	7.8	7.9	7.9	7.9	7.7
Temp. [°C]	21	21	21	21	21	21

 

3) Influence of the Test Item on the immobilisation of Daphnia magna:

Nominal concentration [ppm]	No. of animals	No. of responses		Immobility [%]*
		24 h	48 h	24 h	48 h
0 (Blank)	10	0	0	0	0
	10	0	0
0.08	10	0	0	0	0
	10	0	0
0.14	10	1	4	5	20
	10	0	0
0.25	10	9	9	95	95
	10	10	10
0.45	10	9	10	90	100
	10	9	10
0.78	10	10	10	100	100
	10	10	10

 * calculated for 20 animals

Validity criteria fulfilled:

yes

Conclusions:

The 48-h EC50 of the test item to Daphnia magna under the conditions of the OECD test guideline 202 is 0.17 ppm, corresponding to ca. 0.17 mg/L.

Executive summary:

The 48h acute toxicity of the test item to Daphnia magna was studied under static conditions. Daphnids were exposed to 0 (blank control), 0.08, 0.14, 0.25, 0.45, 0.78 ppm (measured concentration). Mortality/immobilisation were observed daily. 

The 48h EC₅₀was 0.17 ppm, corresponding to ca. 0.17 mg/L. The 48h EC₀ based on mortality/immobilisation was 0.08 ppm, corresponding to ca. 0.08 mg/L. 

 

Based on the results of this study, the test item would be classified in category Acute 1 & Chronic 1 in accordance with the classification system of the GHS.

 

This study is classified as acceptable and satisfies the guideline requirements for an acute toxicity study with freshwater invertebrates.

 

Results Synopsis

Test Organism Age (e.g. 1^stinstar): < 24 h

Test Type: Static

 

EC₀:  0.08 mg/L

EC₅₀:  0.17 mg/L                       95% C.I.:  0.14 -0.19 mg/L

Endpoint(s) Effected:  mortality/immobilisation

This information is used in a read-across approach in the assessment of the substance to be registered.

For details and justification of read-across please refer to the attached report in section 13 of IUCLID.

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

04.10 - 06.10.1990 and 08.09 - 10.09.1990

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: Results from test 1 are not conclusive based on lacking documentation

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

yes

Remarks:

only mortality is recorded

GLP compliance:

not specified

Analytical monitoring:

not specified

Vehicle:

no

Details on test solutions:

Dilution water parameters:
Dilution water: IR-Lake mixture
Specific conductance: 150 micromhos at 25°C

Test organisms (species):

Ceriodaphnia dubia

Details on test organisms:

TEST ORGANISM
- Common name: water flea

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

50 ppm as calcium carbonate

Test temperature:

20°C ± 1°C

pH:

6.87 - 6.99

Dissolved oxygen:

8.5 - 9.3 ppm

Salinity:

not applicable

Conductivity:

140 - 150 micromhos at 25 °C

Nominal and measured concentrations:

First test: 1/ 50/ 100/ 1000 / 2500/ 5000/ 10 000 ppm
Second test: 0.2 / 0.4 / 0.6 / 1 ppm

Details on test conditions:

Not reported

Reference substance (positive control):

no

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

ca. 1.1 other: ppm

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: Results from test 1

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

ca. 0.165 other: ppm

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mortality

Remarks on result:

other: Results from test 1; recalculation of results based on concentration of active ingredient

Details on results:

- Mortality of control: 0
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: no

Results with reference substance (positive control):

n.a.

Reported statistics and error estimates:

no statistics reported

The first test (results see table 1) applied concentrations from 1 ppm up to 10 000 ppm, revealing 90 % death at 1ppm. As noted in handwriting on the test report, the LC₅₀ after an additional acute testing is stated to be 1.1 ppm. However, it is not clear from the data reported how this result was obtained.

The second test (see results in table 2) was conducted with a smaller spacing factor between the concentrations and overall lower concentrations from 0.2 ppm to 1ppm. The LC₅₀ was determined to be > 1.0 ppm.

Table 1: Mixing ratio and results of test # 9009049-02 (conducted: 1990-09-18 to 1990-09-20); Primary stock = 20,000 ppm; * secondary stock = 100 ppm; High conc. at 0 hr.: Dissolved Oxygen = 9.0 ppm, pH = 2.86.

Chamber	Toxicant ppm	Total volum mls	Volume dilution mls	Volume toxicant mls	Volume transfer mls	# of organisms	Deaths at 48 hrs
1	0	100	90	0	10	10	0
2	0	100	90	0	10	10	0
3	1	100	89	*1	10	10	9
4	1	100	89	*1	10	10	9
5	50	100	40	*50	10	10	10
6	50	100	40	*50	10	10	10
7	100	100	89.5	0.5	10	10	10
8	100	100	89.5	0.5	10	10	10
9	1000	100	85	5	10	10	10
10	1000	100	85	5	10	10	10
11	2500	100	77.5	12.5	10	10	10
12	2500	100	77.5	12.5	10	10	10
13	5000	100	65	25	10	10	10
14	5000	100	65	25	10	10	10
15	10000	100	40	50	10	10	10
16	10000	100	40	50	10	10	10

Table 2: Mixing ratio of test medium and toxicant and results of test # 9011113-02 (conducted: 1990-10-04 to 1990-10-06).

Chamber	Toxicant ppm	Total volum mls	Volume dilution mls	Volume toxicant mls	Volume transfer mls	# of organisms	Deaths at 48 hrs
1	0	100	90	0	10	10	0
2	0	100	90	0	10	10	0
3	0.2	100	88	2	10	10	0
4	0.2	100	88	2	10	10	0
5	0.4	100	86	4	10	10	0
6	0.4	100	86	4	10	10	0
7	0.6	100	84	6	10	10	0
8	0.6	100	84	6	10	10	0
9	1	100	80	10	10	10	3
10	1	100	80	10	10	10	5

Validity criteria fulfilled:

not applicable

Conclusions:

The 48 hr LC50 was 1.1 ppm, and 0.165 ppm for the active ingredient.  No sublethal effects were recorded.  

Executive summary:

The 48 hr acute toxicity of the test item to Ceriodaphnia dubia was studied under static conditions. Daphnids were exposed to blank control and test chemical at (nominal) concentration of 1, 50, 100, 1000, 2500, 5000, 10000 ppm (test 1) and 0.2, 0.4, 0.6 and 1 ppm (test 2). Mortality was observed at test termination. The 48 hour LC₅₀ reported in test 1 (after conducting an additional test) was 1.1 ppm, corresponding to 0.165 ppm for the active ingredient. The LC₅₀ from test 2 was determined to be > 1 ppm (> 0.15 ppm a.i.). No sublethal effects were recorded in both test.  

Based on the results of this study the test material would be classified as Acute toxic 1 and Chronic toxic 1 to Ceriodaphnia dubia in accordance with CLP.

This study is classified as supplementary and does not satisfy the guideline requirements for an acute toxicity study with freshwater invertebrates.

 

Results Synopsis

 

Test Organism Age: 1^stinstar

Test Type : Static

 

LC₅₀:  1.1 ppm, and  0.165 ppm for the active ingredient (a.i.), respectively (results reported in test 1 after having conducted an additional experiment)

NOEC: 0.6 ppm, and 0.09 ppm for the a. i., respectively (results from test 2)

                 

Endpoint(s) Effected:  mortality

Reference 3

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

26.-28.11.1991

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:

Part I, 1984

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

No data.

Vehicle:

no

Details on test solutions:

No data.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain/clone: n.a.
- Source: daphnids were bred in the laboratories of the TF Product Ecology under standardized conditions
- Age of parental stock (mean and range, SD): < 24 h

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

136 mg/L CaCO3
Alkalinity: 0.8 mmol/L

Test temperature:

21 °C

pH:

7.8 - 8.2

Dissolved oxygen:

Test media were saturated with oxygen at the beginning of the test.

Salinity:

no data

Conductivity:

no data

Nominal and measured concentrations:

nominal: 0.1, 0.18, 0.32, 0.58 and 1.0 ppm
measured mean concentration: 0.08, 0.14, 0.25, 0.45, 0.78 ppm

Details on test conditions:

TEST SYSTEM
- Test vessel: beaker
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: 250 ml beakers containing 100 ml test medium
- Aeration: no
- Type of flow-through (e.g. peristaltic or proportional diluter): n.a.
- Renewal rate of test solution (frequency/flow rate): /
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: bidistilled water
- Alkalinity: 0.8 mmol/L
- Ca/mg ratio: 4:1
- Intervals of water quality measurement: at beginning and at end of the test

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 h light, 8 h dark
- Light intensity: no data

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : mobility after 24 and 48 h

VEHICLE CONTROL PERFORMED: yes (blank control)

RANGE-FINDING STUDY
- Test concentrations: no details reported
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

ca. 0.17 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% confidence limit

Remarks:

ca. 0.14 - 0.19

Details on results:

Test evaluations were done according to the guidelines by visual assessment of the mobility of the daphnids after 24 and 48 hours.
The EC50 was calculated by using the Probit model and by graphical determination on logarithmic probability paper.
The concentration of the test substance at the beginning and at the end of the test was analysed by the analytical Service Klybeck.

The EC0 and the EC100 after 48 h of exposure was 0.08 mg/L and 0.45 mg/L, respectively.

Results with reference substance (positive control):

EC50 (24 h) = 0.9 ppm (range: 0.8 - 1.5 ppm)

1) Analytical results of test substance measurements:

Nominal concentration [ppm]	Concentration start [ppm]	Concentration end [ppm]	Mean value* [ppm]
0.10	0.08	0.07	0.08
0.18	0.14	0.13	0.14
0.32	0.26	0.23	0.25
0.58	0.47	0.42	0.45
1.00	0.80	0.75	0.78

* used for calculation of EC₅₀ value

2) Oxygen concentration and pH

The oxygen concentration and the pH was controlled at the beginning and at the end of the test.

Start:        - Oxygen: saturated

- pH: 8.0 (highest test concentration)

- Temp.: 21° C

End:

Nominal Conc. [ppm]	0.1	0.18	0.32	0.58	1.0	Blank
Oxygen [%]	96	96	96	97	96	97
pH	7.9	7.8	7.9	7.9	7.9	7.7
Temp. [°C]	21	21	21	21	21	21

 

3) Influence of the Test Item on the immobilisation of Daphnia magna:

Nominal concentration [ppm]	No. of animals	No. of responses		Immobility [%]*
		24 h	48 h	24 h	48 h
0 (Blank)	10	0	0	0	0
	10	0	0
0.08	10	0	0	0	0
	10	0	0
0.14	10	1	4	5	20
	10	0	0
0.25	10	9	9	95	95
	10	10	10
0.45	10	9	10	90	100
	10	9	10
0.78	10	10	10	100	100
	10	10	10

 * calculated for 20 animals

Validity criteria fulfilled:

yes

Conclusions:

The 48-h EC50 of the test item to Daphnia magna under the conditions of the OECD test guideline 202 is 0.17 ppm, corresponding to ca. 0.17 mg/L.

Executive summary:

The 48h acute toxicity of the test item to Daphnia magna was studied under static conditions. Daphnids were exposed to 0 (blank control), 0.08, 0.14, 0.25, 0.45, 0.78 ppm (measured concentration). Mortality/immobilisation were observed daily. 

The 48h EC₅₀was 0.17 ppm, corresponding to ca. 0.17 mg/L. The 48h EC₀ based on mortality/immobilisation was 0.08 ppm, corresponding to ca. 0.08 mg/L. 

 

Based on the results of this study, the test item would be classified in category Acute 1 & Chronic 1 in accordance with the classification system of the GHS.

 

This study is classified as acceptable and satisfies the guideline requirements for an acute toxicity study with freshwater invertebrates.

 

Results Synopsis

Test Organism Age (e.g. 1^stinstar): < 24 h

Test Type: Static

 

EC₀:  0.08 mg/L

EC₅₀:  0.17 mg/L                       95% C.I.:  0.14 -0.19 mg/L

Endpoint(s) Effected:  mortality/immobilisation

Description of key information

The 48h acute toxicity of the test item to Daphnia magna was studied under static conditions in accordance with OECD test guideline 202 (Mätzler, 1992). Daphnids were exposed to 0 (blank control) and mean measured concentrations of 0.08, 0.14, 0.25, 0.45, 0.78 ppm. The 48h EC₅₀ was 0.17 ppm, corresponding to ca. 0.17 mg/L. 

As supporting study, one additional test on the target substance is presented. However, this test is not fulfilling the OECD TG criteria, and is only very briefly documented (Anonymous, 1990). The determined 48h LC₅₀ for Ceriodaphnia dubia of 0.165 ppm (based on the active ingredient concentration) is in line with the findings of Mätzler (1992).

The 48h EC₅₀ of ca. 0.17 mg/L (Mätzler, 1992), which is based on the test item containing > 90 % active ingredient, is carried forward as key value in the risk assessment.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.17 mg/L

Additional information

The key information is used in a read-across approach in the assessment of the substance to be registered.

For details and justification of read-across please refer to the attached report in section 13 of IUCLID.