Amides, C8-18 (even-numbered), C18unsatd, N-[3-(dimethylamino)propyl]

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

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

Adequacy of study:

key study

Study period:

72 h

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study conducted according to guideline method with restriction. Restriction: The stability of the test concentrations was not verified with analytical monitoring.

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Qualifier:

according to guideline

Guideline:

other: DIN 38412/9 (May 1989)

GLP compliance:

not specified

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Source: Pflanzenphysiologisches Institut Göttingen
- Age of inoculum (at test initiation):
- Method of cultivation: Cultivation in Erlenmeyer flasks (300 mL), filled with culture medium. Constant movement on a mechanical shaker. Illumination with white fluorescent tube (2000 lux).

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test temperature:

23 ± 2 °C

pH:

not reported

Nominal and measured concentrations:

nominal concentrations: control; 0.025; 0.05; 0.075; 0.1; 0.25; 0.5; 0.75 mg/L

Details on test conditions:

TEST SYSTEM
- Initial cells density: 10 000 cells/ mL
- Control end cells density: 271E3 cells/mL
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 3


GROWTH MEDIUM
- Standard medium used: not reported, probably yes


OTHER TEST CONDITIONS
- Adjustment of pH: not reported
- Photoperiod: constant illumination
- Light intensity and quality: 2000 lux with white fluorescent tubes


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: fluorimeter at Ex 485; Em 685 nm in 1 mL cuvettes

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

0.18 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

0.05 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

0.36 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

0.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Details on results:

- Exponential growth in the control (for algal test): yes

Reported statistics and error estimates:

statistcal method: linear regression

Avarage cell number [x1000/mL]

Concentration	24 h	48 h	96 h
Control	21	96	271
0.025	23	118	291
0.05	31	77	263
0.075	21	50	230
0.1	13	48	209
0.25	16	40	177
0.5	13	17	43
0.75	11	12	13

Biomass after 72 h:

Concentration	Biomass integral x 1000	% Inhibition
Control	5460
0.025	6276	- 15
0.05	5148	6
0.075	3864	29
0.1	3612	34
0.25	2868	47
0.5	636	88
0.75	108	98

Growth rater after 72 h:

Concentration	Growth rate	% Inhibition
Control	45,8
0.025	46,8	- 2
0.05	45,4	1
0.075	43,5	5
0.1	42,2	8
0.25	39,9	13
0.5	20,3	56
0.75	3,6	92

Validity criteria fulfilled:

yes

Conclusions:

Static acute toxicity test according to OECD TG 201 with Scenedesmus subspicatus. No analytical monitoring was made. Therefore the test results are based on nominal concentration.
ErC50 (72 h) = 0.36 mg/L
ErC10 (72 h) = 0.1 mg/L
EbC50 (72 h) = 0.18 mg/L
EbC10 (72 h) = 0.05 mg/L

Executive summary:

In a 72 hour toxicity study conducted according to OECD Guideline 201, the cultures of Scenedesmus subspicatus were exposed to Amides, C8-18 even numbered, N-[3-(dimethylamino)propyl] at nominal concentrations of 0 (control), 0.025, 0.05, 0.075, 0.1, 0.25, 0.5 and 0.75 mg/L under static conditions.

The test meets validity criteria of the guideline. No analytical monitoring was made. Therefore the test results are based on nominal concentration.

ErC50 (72 h) = 0.36 mg/L

ErC10 (72 h) = 0.1 mg/L

EbC50 (72 h) = 0.18 mg/L

EbC10 (72 h) = 0.05 mg/L

Description of key information

72 h ErC10 = 0.1 mg/L, 72 h ErC50 = 0.36 mg/L (nominal) (Scenedesmus subspicatus), OECD TG 201, static, no data on GLP, RL2; tested source substance: Amides, C8-18 even numbered, N-[3-(dimethylamino)propyl];

Read across target substance: Amides, C8-18 even numbered, C18 unsatd., N-[3-(dimethylamino)propyl]

Key value for chemical safety assessment

EC50 for freshwater algae:

0.36 mg/L

EC10 or NOEC for freshwater algae:

0.1 mg/L

Additional information

For the assessment of the toxicity of Amides, C8-18, C18 unsatd, N-[3-(dimethylamino)propyl] to freshwater algae a study conducted with the closely related source substance Amides, C8-18 even numbered, N-[3-(dimethylamino)propyl] is available. A justification for read-across is given in IUCLID section 13.

In a 72 hour toxicity study conducted according to OECD Guideline 201, the cultures of Scenedesmus subspicatus were exposed to Amides, C8-18 even numbered, N-[3-(dimethylamino)propyl] at nominal concentrations of 0 (control), 0.025, 0.05, 0.075, 0.1, 0.25, 0.5 and 0.75 mg/L under static conditions.

The test meets validity criteria of the guideline. No analytical monitoring was made. Therefore the test results are based on nominal concentration.

ErC50 (72 h) = 0.36 mg/L

ErC10 (72 h) = 0.1 mg/L

EbC50 (72 h) = 0.18 mg/L

EbC10 (72 h) = 0.05 mg/L