N,N-dimethyldecylamine N-oxide

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1976-04 to 1977-02

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Deviations:

not specified

GLP compliance:

no

Remarks:

the study pre-dates GLPs

Analytical monitoring:

yes

Details on sampling:

- Concentrations: all concentrations
- Sampling method: Samples were taken from test vessels on day 0, and every 3-5 days throughout the 21-day test.
- Sample storage conditions before analysis: Preserved with 1% formaldehyde for anionics, or H2SO4 at pH 2 for nonionics, and stored at 5 C until analysis.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Direct dilution of the appropriate amount of test substance into blended well water
- Eluate: N/A
- Differential loading: N/A
- Controls: Blended well water
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): N/A
- Concentration of vehicle in test medium (stock solution and final test solution(s) including control(s)): N/A
- Evidence of undissolved material (e.g. precipitate, surface film, etc): None

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Strain/clone: N/A
- Justification for species other than prescribed by test guideline: N/A
- Source: In-house culture
- Age of parental stock (mean and range, SD): <12 h
- Feeding during test
- Food type: ground trout chow/alfalfa mixture, 1000 mg/L
- Amount: 5 mg/L
- Frequency: Each diluter cycle


ACCLIMATION
- Acclimation period: Not specified
- Acclimation conditions (same as test or not): N/A
- Type and amount of food: N/A
- Feeding frequency: N/A
- Health during acclimation (any mortality observed): N/A


QUARANTINE (wild caught)
- Duration: N/A
- Health/mortality: N/A


METHOD FOR PREPARATION AND COLLECTION OF EARLY INSTARS OR OTHER LIFE STAGES: Young were manually siphoned from existing culture units

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Post exposure observation period:

None

Hardness:

120 +/- 18 mg/L CaCO3

Test temperature:

21 +/- 1 C

pH:

7.5 +/- 0.2 SU

Dissolved oxygen:

8.9 +/- 0.4 mg/L

Salinity:

N/A

Nominal and measured concentrations:

Mean Measured Concentrations - Control, 0.08, 0.17, 0.34, 0.70, and 1.35 mg/L C12.7 Amine Oxide (active ingredient). Nominal concentrations not available in the study report.

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: 1 liter glass beakers, 1 L test solution
- Aeration: N/A
- Type of flow-through (e.g. peristaltic or proportional diluter): Mount and Brungs proportional diluter, with modifications
- Renewal rate of test solution (frequency/flow rate): 125 ml per 20 min cycle, or one chamber volume every 2.5 hr.
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- No. of vessels per vehicle control (replicates): N/A
- Biomass loading rate: N/A


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Blended well water
- Total organic carbon: N/A
- Particulate matter: N/A
- Metals: N/A
- Pesticides: N/A
- Chlorine: N/A
- Alkalinity: N/A
- Ca/mg ratio: N/A
- Conductivity: N/A
- Salinity: N/A
- Culture medium different from test medium: No
- Intervals of water quality measurement: Daily


OTHER TEST CONDITIONS
- Adjustment of pH: N/A
- Photoperiod: N/A
- Light intensity: N/A


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Mortality, 24 hr, 96 hr, 7 days, then daily to end of test. Reproduction, daily beginning day 7 or 8 to end of test.


VEHICLE CONTROL PERFORMED: no


RANGE-FINDING STUDY
- Test concentrations: N/A
- Results used to determine the conditions for the definitive study: N/A

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

1.01 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality

Remarks on result:

other: 95% CL 0.85-1.21 mg/L

Duration:

21 d

Dose descriptor:

LC50

Effect conc.:

0.96 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality

Remarks on result:

other: 95% CL 0.90-1.03 mg/L

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

0.88 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

other: Total young production

Remarks on result:

other: 95% CL 0.77-1.04 mg/L

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

1.01 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

other: Average brood size

Remarks on result:

other: 95% CL 0.95-1.07 mg/L

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

1.04 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

other: Percentage of days reproduction occurred

Remarks on result:

other: 95% CL 0.98-1.11 mg/L

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.7 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

other: Parent (Fo) Survival and Reproduction (Mean Brood Size; Total # of young)

Remarks on result:

other: CL not provided

Details on results:

- Mortality of parent animals: % mortality, day 21- Control-10%; 0.08 mg/L-30%; 0.17 mg/L-20%; 0.34 mg/L-10%, 0.70 mg/L-15%; 1.35 mg/L-100%
- No. of offspring produced per day per female: N/A
- Body length and weight of parent animals: N/A
- Type and number of morphological abnormalities: N/A
- Type and number of behavioural abnormalities: N/A
- Number of males and females (parental): N/A
- Time to first brood release or time to hatch- 7 or 8 days
- Egg development time: N/A
- Brood size: Mean-Control-1.78; 0.08 mg/L-2.92; 0.17 mg/L-5.32; 0.34 mg/L-5.58, 0.70 mg/L-6.06; 1.35 mg/L-0
- Time to sexual maturity: N/A
- Type and magnitude of biochemical changes: N/A
- Other biological observations: N/A
- Effect concentrations exceeding solubility of substance in test medium: N/A

Results with reference substance (positive control):

N/A

Reported statistics and error estimates:

All results were calculated with a computerized probit analysis program after Finney (1964, 1971). Survival data for 96 hr and 21 days was used to calculate LC50 values and confidence limits. All results were calculated based on mean measured concentrations of test material.

Validity criteria fulfilled:

yes

Conclusions:

The 21 day NOEC of C12/C14 amine oxide to Daphnia magna was 0.70 mg AO/L, based on survival and reproduction. The 21 day LC50 was 0.96 mg AO/L. Results are based on the mean measured concentration.

Executive summary:

The long-term toxicity of C12/C14 amine oxide was evaluated in a 21 day survival and reproduction test with Daphnia magna, following the OECD 211 guideline. Four replicates per concentration, 5 organisms per replicate, were tested in a flow-through system (a modified Mount and Brungs proportional diluter). Mean measured test concentrations were: Control, 0.08, 0.17, 0.34, 0.70, and 1.35 mg AO/L.

Survival was monitored at 24 hr., 96 hr., 7 days, and daily thereafter. Reproduction was monitored beginning with the production of the first brood on day 7 or 8, and daily thereafter. LC50s and EC50s were calculated by probit analysis. Results are based on the mean measured concentration of the active ingredient. The 21 -day NOEC was 0.70 mg AO/L, based on both survival and reproduction. The 21 day LC50 was 0.96 mg AO/L (95% CL = 0.90 -1.03 mg AO/L). The 21-day EC50’s, based on total young production, average brood size, and % days reproduction occurred, were 0.88 mg AO/L, 1.01 mg AO/L, and 1.04 mg AO/L, respectively.

Reference 2

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

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

Adequacy of study:

key study

Study period:

1976-04 to 1977-02

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
Both the target and source substances contain identical functional groups and differ only by the C-chain length. The ecotoxicological properties of these substances will be similar or predictable.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
Source: Amines, C12-14 (even numbered) -alkyldimethyl, N-oxides (EC 931-292-6; C12-14 AO)
Target: N,N-dimethyldecylamine N-oxide (EC 220-020-5; CAS 2605-79-0; C10 AO)

3. ANALOGUE APPROACH JUSTIFICATION
The target and source substances contain identical functional groups. The only difference between the substances is the alkyl chain length (C10 in the target and mainly C12 in the source). In the acute studies (IUCLID Section 6.1.3) it was found that toxicity to daphnia increased slightly as the chain length increased from C12 AO to C14 AO with C12-14 AO having intermediate toxicity between the two monoconstituents. It is expected that a similar trend would be seen in the chronic studies and on this basis the study with C12-14 AO would represent a worst case for C10 AO.

4. DATA MATRIX
Chronic toxicity studies:
Target: No data
Source (C12-14 AO): 21-d NOEC = 0.7 mg AO/L (Daphnia magna)
Acute toxicity studies:
Target: No data
Source (C12 AO): 48-h EC50 = 3.9 mg AO/L; 48-h EC50 = 4.24 mg AO/L
Source (C14 AO): 48-h EC50 = 2.63 mg AO/L
Source (C12-14 AO): 48-h EC50 = 3.1 mg AO/L; 48-h EC50 = 2.9 mg AO/L; 48-h EC50 = 4.2 mg AO/L

Reason / purpose for cross-reference:

read-across source

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

1.01 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality

Remarks on result:

other: 95% CL 0.85-1.21 mg/L

Duration:

21 d

Dose descriptor:

LC50

Effect conc.:

0.96 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

mortality

Remarks on result:

other: 95% CL 0.90-1.03 mg/L

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

0.88 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

other: Total young production

Remarks on result:

other: 95% CL 0.77-1.04 mg/L

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

1.01 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

other: Average brood size

Remarks on result:

other: 95% CL 0.95-1.07 mg/L

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

1.04 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

other: Percentage of days reproduction occurred

Remarks on result:

other: 95% CL 0.98-1.11 mg/L

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.7 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

act. ingr.

Basis for effect:

other: Parent (Fo) Survival and Reproduction (Mean Brood Size; Total # of young)

Remarks on result:

other: CL not provided

Description of key information

No chronic daphnia toxicity studies have been performed using C10 amine oxide. Data are read across from C12-14 AO as this is expected to represent a worse case for the shorter alkyl chain length as demonstrated from the acute daphnia results for C12 AO, C14AO and C12-14AO.

One long term (21 days) toxicity to Daphnia magna study is available for C12-14 AO. A No effect concentration of 0.7 mg AO/L was reported in the study.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.7 mg/L

Additional information

No chronic daphnia toxicity studies have been performed using C10 amine oxide. Data are read across from C12-14 AO as this is expected to represent a worse case for the shorter alkyl chain length as demonstrated from the acute daphnia results for C12 AO, C14AO and C12-14AO.

The long-term toxicity of the C12-14 AO was evaluated in a 21 day survival and reproduction test with Daphnia magna, following the OECD 211 guideline [Maki AW (1977)]. Four replicates per concentration, 5 organisms per replicate, were tested in a flow-through system. Mean measured test concentrations were: 0, 0.08, 0.17, 0.34, 0.70, and 1.35 mg AO/L.

Survival was monitored at 24 hours, 96 hours, 7 days, and daily thereafter. Reproduction was monitored beginning with the production of the first brood on day 7 or 8, and daily thereafter. LC50s and EC50s were calculated by probit analysis. Results are based on the mean measured concentration of the amine oxide. The 21 -day NOEC was 0.70 mg AO/L, based on both survival and reproduction. The 21 day LC50 was 0.96 mg AO/L. The 21-day EC50’s, based on total young production, average brood size, and % days reproduction occurred, were 0.88 mg AO/L, 1.01 mg AO/L, and 1.04 mg AO/L, respectively.