3-methyl-2-[(1-methyl-2-phenyl-1H-indol-3-yl)azo]thiazolium chloride

Long-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1989-05-04 to 1989-05-11

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1989

Report date:

1989

Materials and methods

Test guideline

Test guideline 1

Guideline:

other: Short Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms

Version / remarks:

USEPA, 1985 (EPA/600/4-85/014)

Test guideline 2

Guideline:

other: North Carolina Ceriodaphnia Chronic Effluent Bioassay Procedure

Version / remarks:

December 1985, revised June 1988, North Carolina Department of Natural Resources and Community Development, Division of Environmental Management, Water Quality Section

Principles of method if other than guideline:

- Principle of test: the test item is diluted 5:1 with spring water and treated with sludge from City of Columbis WWTP in 1:4 ratio. Solution is aerated for 24 hours and filtered before tested. In an additional test the sludge without any test item is tested for toxicity.
- Parameters analysed / observed: mortality, offspring

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

3-methyl-2-[(1-methyl-2-phenyl-1H-indol-3-yl)azo]thiazolium chloride

EC Number:

255-785-4

EC Name:

3-methyl-2-[(1-methyl-2-phenyl-1H-indol-3-yl)azo]thiazolium chloride

Cas Number:

42373-04-6

Molecular formula:

C19H17N4S.Cl

IUPAC Name:

3-methyl-2-[(1-methyl-2-phenyl-1H-indol-3-yl)azo]thiazolium chloride

Test material form:

solid

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Dye Preparation: 30 mg/L dye diluted 5:1 with spring water and treated with sludge from City of Columbis WWTP in 1:4 ratio. Solution aerated for 24 hours and the solution filtered before tested.
- Controls: one control 100% spring water, additional test for control of toxicity of sludge
- Evidence of undissolved material (e.g. precipitate, surface film, etc.): stock solution was filtrated before using for dilutions

Test organisms

Test organisms (species):

Ceriodaphnia sp.

Details on test organisms:

TEST ORGANISM
- Age at test start: 2 to 24 hours
- Feeding during test: yes
- Food type: green alga Selenastrum capricornutum
- Amount: at rate of approx. 2000000 cells/mL per day

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

7 d

Remarks on exposure duration:

test solutions were renewed on days 2 and 5 with reproduction counts made at that time.

Test conditions

Test temperature:

25 +/- 1°C

pH:

6.92 - 7.60

Dissolved oxygen:

6.50 - 8.50 ppm

Nominal and measured concentrations:

control, and dilutions of 5, 15, 30 and 50% of the stock solution

Details on test conditions:

TEST SYSTEM
- Test vessel: 1ounce filled with 15 mL of solution
- No. of organisms per vessel: 1
- No. of vessels per concentration (replicates): 10
- No. of vessels per control (replicates): 10

OTHER TEST CONDITIONS
- Photoperiod: 16h light/ 8h darkness

Reference substance (positive control):

not specified

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

7 d

Dose descriptor:

NOEC

Effect conc.:

50 other: %

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Remarks on result:

other: corresponding to 2.25 mg/L

Effect concentrations 2

Duration:

7 d

Dose descriptor:

NOEC

Effect conc.:

50 other: %

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

Sludge control: the test was performed in the same way as the test with test item.
Concentrations of sludge (without test item): 5, 15, 30, 50% and a control.
Result: sludge is not chronically toxic to Ceriodaphnia at the tested concentrations.

Any other information on results incl. tables

Results of the main test

Concentration of the test item	Average Offspring	Mortality [%]
Control	15	10
5%	19	0
15%	20	0
30%	17	10
50%	15	10

Results of the sludge control test

Concentration of sludge	Average Offspring	Mortality [%]
Control	15	10
5%	16	0
15%	20	0
30%	19	0
50%	26	0

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

Mortality in negative control 10%, average # offspring = 19

Conclusions:

The 7-d NOEC (reproduction) to Ceriodaphnia sp. was determined at 2.25 mg/L nominal.