1,3,3-trimethyl-2-[2-(1-methyl-2-phenyl-1H-indol-3-yl)vinyl]-3H-indolium chloride

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1990

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2-[2-(2,3-dihydro-2-methyl-1H-indol-1-yl)vinyl]-1,3,3-trimethyl-3H-indolium chloride

EC Number:

228-800-7

EC Name:

2-[2-(2,3-dihydro-2-methyl-1H-indol-1-yl)vinyl]-1,3,3-trimethyl-3H-indolium chloride

Cas Number:

6359-50-8

Molecular formula:

C22H25N2.Cl

IUPAC Name:

1,3,3-trimethyl-2-[2-(2-methyl-2,3-dihydro-1H-indol-1-yl)vinyl]-3H-indolium chloride

Test material form:

solid: particulate/powder

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Details on test solutions:

Stock solution of 100 mg/L prepared and diluted with test medium accoridng to guideline

Test organisms

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Source (laboratory, culture collection): Institute for plant physiology, University of Göttingen

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Test temperature:

21°C

pH:

7.4 - 9.2

Nominal and measured concentrations:

Nominal: 0 (control), 0.01, 0.032, 0.1, 0.32, 1.0, 3.2, 10.0, 32.0 and 100.0 mg/L

Details on test conditions:

Water quality parameters and dilution water (test medium) in accordance with test guideline
Ligh regime: continuous light

Reference substance (positive control):

not specified

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

1.2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 2

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 3

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

0.52 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Effect concentrations 4

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

1.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Details on results:

see table

Any other information on results incl. tables

concentration [mg/L]	area under the growth curve	inhibition of algae growth compared to control [%]	Growth rate	inhibition of growth rate compared to control [%]
control	697222		1.41
0.01	716667	-7.5	1.42	-0.65
0.032	681111	0.2	1.41	0.55
0.10	723333	-8.4	1.43	-0.87
0.32	665556	1.5	1.40	1.10
1.0	546667	20.9	1.33	5.73
3.2	134444	76.5	0.87	38.78
10.0	10000	98.0	0.00	100.00
32.0	10000	99.6	0.00	100.00
100.0	11111	99.5	0.04	97.52

negative values considered as enhancement of growth compared to the control

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The 72-h ErC10 and ErC50 to Desmodesmus subspicatus were determined to be 1.2 and 4.0 mg/L, respectively. The substance is acutely harmful to freshwater green algae.