1,2-Propanediamine, N1-(2-aminoethyl)-3-(4-ethoxyphenyl)-, hydrochloride (1:2), (2S)-

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

May - Jul 1996

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

Principles of method if other than guideline:

not relevant

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

6.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: 5.9 - 7.2

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

18.6

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 13.0 - 24.1

Table 1: Inhibition of the growth of Scenedesmus subspicatus after 72 hours exposure to ZK 156454

Concentration (mg/L)	Inhibition in percent
of ZK 156454	biomass (inteqral)	growth rate
0.0	0	0
3.1	28.7	9.4
6.2	47.1	18.1
12.5	69.8	31.6
25.0	87.0	59.8
49.9	94.4	86.6

Validity criteria fulfilled:

yes

Conclusions:

ZK 156454 had an inhibitory, concentration-related effect on the growth of Scenedesmus subspicatus. The EbC50 (biomass) was 6.5 (5.9-7.2) mg/L, the ErC50 (growth rate) was 18.6 (13.0-24.1) mg/L, including the 95% confidence limits.

Executive summary:

The purpose of this study was to determine the effects of the test compound Triamin.Dihydrochlorid (ZK 156454) on the

growth of the green algae Scenedesmus subspicatus. The study was conducted in agreement with the OECD guideline no. 201.

The test substance ZK 156454 was incubated in an aqueous solution including nutrients with an algae population of Scenedesmus subspicatus for a test duration of approximately 72 hours.

The nutrient solution was made up of mainly nitrate, phosphates and some trace elements. The test concentrations were 0, 3.1, 6.2, 12.5, 25.0 and 49.9 mg/I (nominal). The algae were exposed to each concentration in triplicate. Six vessels were prepared for the control. The algae were incubated in an incubator shaker under continuous light.

As a parameter for the growth of the algae population, the cell concentrations of the test and control solutions were counted with an electronic particle counter ("Coulter Counter"). The increase of biomass and the growth rate were calculated on the basis of the cell counts. The calculated biomass and growth rate of each concentration were compared to those of the controls, and the inhibition was calculated. ZK 156454 had an inhibitory, concentration-related effect on the growth of Scenedesmus subspicatus.

Description of key information

ZK 156454 had an inhibitory, concentration-related effect on the growth of Scenedesmus subspicatus. The EbC50 (biomass) was 6.5 (5.9-7.2) mg/L, the ErC50 (growth rate) was 18.6 (13.0-24.1) mg/L, including the 95% confidence limits.

Key value for chemical safety assessment

EC50 for freshwater algae:

6.5 mg/L