13-Docosenamide, N-[3-(dimethylamino)propyl]-, (13Z)-

Toxicity to aquatic algae and cyanobacteria

Administrative data

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:

June 2005 - December 2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP-compliant guideline study (OECD)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2005

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

N-[3-(dimethylamino)propyl]docosonamide, lactic acid salt

IUPAC Name:

N-[3-(dimethylamino)propyl]docosonamide, lactic acid salt

Test material form:

not specified

Details on test material:

Description: white solid
Purity: 99.7%

Sampling and analysis

Analytical monitoring:

yes

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

TEST ORGANISM
- Common name: Scenedesmus subspicatus
- Strain: CCAP 276/20
- Source (laboratory, culture collection): Culture Collection of Algae and Protozoa (CCAP), Dunstaffnage Marine Laboratory, Oban, Argyll, Scotland
- Age of inoculum (at test initiation):
- Method of cultivation:

ACCLIMATION
- Acclimation period:
- Culturing media and conditions (same as test or not):
- Any deformed or abnormal cells observed:

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Test temperature:

24±1°C

Nominal and measured concentrations:

Definitive test - Nominal test concentration of the test media: 1.00 - 2.00 - 4.0 - 8.0 - 16 mg/L
Definitive test - Geometric mean concentration of the centrifugated test media: 0.40 - 0.31 - 2.1 - 5.3 - 15 mg/L
Definitive test - Geometric mean concentration of the untreated test media: 0.44 - 0.89 - 2.8 - 6.9 - 15 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 250 ml glass conical flask bugged with polyurethane foam bung
- Type: closed
- Initial cells density: 1.09E+04
- Control end cells density: 3.85E+05

GROWTH MEDIUM
- Standard medium used: no
- Detailed composition if non-standard medium was used:
NaNO3: 25.5 mg/L
MgCl2.6H2O: 12.164 mg/L
CaCl2.2H2O: 4.41 mg/L
MgSO4.7H2O: 14.7 mg/L
K2HPO4: 1.044 mg/L
NaHCO3: 15.0 mg/L
H3BO3: 0.1855 mg/L
MnCl2.4H2O: 0.415 mg/L
Zn.Cl2: 0.00327 mg/L
FeCl3.6H2O: 0.159 mg/L
CoCl2.6H2O: 0.00143 mg/L
Na2MoO4.2H2O: 0.00726 mg/L
CuCl2.2H2O: 0.000012 mg/L
Na2EDTA.2H2O: 0.30 mg/L
Na2SeO3.5H2O: 0.000010 mg/L

OTHER TEST CONDITIONS
- Sterile test conditions: yes
- Adjustment of pH: 7.5 ± 0.1
- Photoperiod: no (continuous illumination)
- Light intensity and quality: ca. 7000 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations: haemocytometer and light microscope

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2
- Test concentrations: 1.0 - 2.0 - 4.0 - 8.0 - 16 mg/L

Reference substance (positive control):

not specified

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

ca. 2.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% confidence limits: 2.3-3.1 mg/L

Effect concentrations 2

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

ca. 1.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: 95% confidence limits: 1.4-1.8 mg/L

Effect concentrations 3

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

ca. 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Effect concentrations 4

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

ca. 1.6 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Remarks:

(centrifugated test media)

Basis for effect:

growth rate

Remarks on result:

other: 95% confidence limits: 1.4-1.8 mg/L

Effect concentrations 5

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

ca. 0.73 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Remarks:

(centrifugated test media)

Basis for effect:

biomass

Remarks on result:

other: 95% confidence limits: 0.61-0.88 mg/L

Effect concentrations 6

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

ca. 0.4 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Remarks:

(centrifugated test media)

Effect concentrations 7

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

ca. 2.1 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Remarks:

(untreated test media)

Basis for effect:

growth rate

Remarks on result:

other: 95% confidence limits: 1.8-2.4 mg/L

Effect concentrations 8

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

ca. 0.87 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Remarks:

(untreated test media)

Basis for effect:

biomass

Remarks on result:

other: 95% confidence limits: 0.71-1.1 mg/L

Effect concentrations 9

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

ca. 0.44 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Remarks:

(untreated test media)

Any other information on results incl. tables

Table 1. Inhibition of biomass and growth rate

Nominal concentration (mg/L)	Mean % inhibition (biomass)	Mean % inhibition (growth rate)
Control	–	–
1.0	[7]	[2]
2.0	67	35
4.0	89	69
8.0	96	89
16.0	100	107

[Increase in growth as compared to the controls]

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

According to a GLP-compliant guideline study (OECD 201), the test material (N-[3-(dimethylamino)propyl]docosonamide, lactic acid salt) is toxic to aquatic algae (S. subspicatus: ErC50 (72h) = 1.6-2.1 mg/L, NOEC (72h) = 0.40-0.44 mg/L; based on geometric mean measured test concentrations).

Executive summary:

A study was performed to assess the effect of the test material on the growth of the green alga Scenedesmus subspicatus. The method followed that described in the OECD Guidelines for Testing of Chemicals (1984) no. 201, "Alga, Growth Inhibition Test" referenced as Method C.3 of Commission Directive 92/69/EEC (which constitutes Annex V of Council Directive 67/548/EEC).

Following a preliminary range-finding test, Scenedesmus subspicatus was exposed to an aqueous dispersion of the test material at nominal concentrations of 1.0, 2.0, 4.0, 8.0 and 16 mg/L (three replicate flasks per test concentration) for 72 hours, under constant illumination and shaking at a temperature of 24±1°C. The concentrations of test solutions were measured both in dispersed condition (no treatment) and in dissolved condition (treatment by centrifugation [40,000g, 30 min.]).

Based on the nominal test concentration of the test media, the EbC50 (72h) value was 1.6 mg/L (95% CL: 1.4-1.8 mg/L), the ErC50 (72h) value was 2.7 mg/L (95% CL: 2.3-3.1 mg/L) and the No Observed Effect Concentration at 72 hours was 1.0 mg/L.

Based on the geometric mean measured test concentration of the centrifugated test media, the EbC50 (72h) value was 0.73 mg/L (95% CL: 0.61-0.88 mg/L), the ErC50 (72h) value was 1.6 mg/L (95% CL: 1.4-1.8 mg/L) and the No Observed Effect Concentration at 72 hours was 0.40 mg/L.

Based on the geometric mean measured test concentration of the untreated test media, the EbC50 (72h) value was 0.87 mg/L (95% CL: 0.71-1.1 mg/L), the ErC50 (72h) value was 2.1 mg/L (95% CL: 1.8-2.4 mg/L) and the No Observed Effect Concentration at 72 hours was 0.44 mg/L.