4-[3-(1-naphthylamino)propyl]morpholine

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

February 24, 1998 to May 13, 1998

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: While the study was conducted according to OECD TG 202 and in accordance with the Principles of Good Laboratory practice (GLP), the stability of the test substance under test conditions was not verified analytically.

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

yes

Remarks:

Certain minor deviations (eg. non verfification of the instrument used to measure conductivity and others) were noted, overall these did not impact the outcome of the study

Principles of method if other than guideline:

not applicable

GLP compliance:

yes

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
not applicable

Analytical monitoring:

no

Details on sampling:

not applicable

Vehicle:

yes

Details on test solutions:

Dimethylformamide was used as a vehicle to dissolve the test material before adding to the dilution water for both the range finding and definitive study.
For the difinitive test, a stock solution with a nominal concentration of 100000 mg/L was prepared by bringing 5 grams of the test substance to a total volume 50 ml with dimethylformamide. Appropriate volumes of the stock solution were added to test vessels containing 15 liters of dilution water. Nominal concentrations used were 1.3, 2.2, 3.6, 6.0 and 10 mg/L.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Strain: Daphnia magna
- Source: in-house from a culture originally procured from Aquatic BioSystems Inc., USA
- Age at study initiation: Juvenile daphnids < 24 hours old were used
- Method of breeding: Prior to testing, the daphnid culture was maintained in 100% dilution water under static, renewal conditions and the test organisms were not treated for disease. During the 48 hours prior to begining of the test there was no mortality and at the begining of the test, organisms were apparently free of disease, injuries and abnormalities.
- Feeding during test: not fed during the test
- Food type: The daphnids were fed with freshwater algae, Selenastrum capricornutum, and a mixture of yeast and trout chow (Lot number DC02) once each day before the test.

ACCLIMATION
- Acclimation period: 14 days
- Acclimation conditions (same as test or not): yes
- The daphnids were fed with freshwater algae, Selenastrum capricornutum, and a mixture of yeast and trout chow (Lot number DC02) once each day before the test.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

not applicable

Hardness:

160 mg/l as CaCO3

Test temperature:

ranged between 19.5-20.8 °C

pH:

ranged between 7.7-7.9

Dissolved oxygen:

ranged between 8.6 - 8.8 mg/l

Salinity:

not applicable

Conductivity:

570 - 580 umhos/cm

Nominal and measured concentrations:

Range finding test - 0.10, 1.0 and 10 mg/L (nominal) + solvent control + dilution water control
Definitive study - 1.3, 2.2, 3.6, 6.0 and 10 mg/L (nominal) + solvent control + dilution water control

Details on test conditions:

A range finding test with 4-(3-(1-naphthylamino)propyl) morpholine was conducted with three concentrations (0.10, 1.0 and 10 mg/L), a solvent control (86 mg/L dimethylformamide) and a dilution water control. After 48 hours of exposure there was 100% survival in the control, solvent control and at 0.10 and 1.0 mg/l and 10% survival at 10 mg/L.

The definitive toxicity test with 4-(3-(1-naphthylamino)propyl) morpholine was conducted with 5 concentrations (1.3, 2.2, 3.6, 6.0 and 10 mg/L), a solvent control (95 mg/L dimethylformamaide) and a dilution water control. Ten daphnids were added to each of the two replicate controls and tested concentrations. The test was performed in loosely covered 300 ml glass beakers that each contained 250 ml solution (media depth was approximately 8 cm). Test vessels were randomly arranged for the 48 hour test. A 16:8 hour photoperiod was maintained, loading rate was ≤ 40 daphnids/liter. The number of surviving organisms and the occurence of sublethal effects (immobilization, loss of equilibrium, erratic swimming, loss of reflex, excitability, discolouration or change in behaviour) were determined visually and recorded initially and after 24 and 48 hours. Dead daphnids were removed when observed.
Dissolevd oxygen, pH, conductivity and temperature were measured and recorded daily in each test chamber. Temperature was recorded continuously in a beaker of water incubated among the test vessels.

Reference substance (positive control):

no

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

7.3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 95% CI - 6.3 - 8.8 mg/l

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

5.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 95% CI - 4.4 - 6.0 mg/l

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

2.2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

No insoluble material was observed at any time during the definitive test. 100% survival with no sublethal effects were noted in the control and solvent control dose groups. Exposure of daphnids, Daphnia magna to 4-(3-(1-naphthylamino)propyl) morpholine resulted in the following effective concentration (EC50's) -
24 hour EC50 - 7.3 mg/l (95% CI: 6.3 - 8.8 mg/l)
48 hour EC50 - 5.1 mg/l (95% CI: 4.4 - 6.0 mg/l).
The 48 hour NOEC was 2.2 mg/l.

Results with reference substance (positive control):

not applicable

Reported statistics and error estimates:

The probit method was used to calculate the 24 and 48 hour median effective concentrations using nominal concentrations and the number of live, mobile daphnids. The no observed effect concentration is the highest concentration of test substance that allows at least 90% survival of exposed organisms and does not cause sublethal effects.

None

Validity criteria fulfilled:

yes

Conclusions:

Exposure of daphnids, Daphnia magna to Mortrace MP resulted in the following effective concentration (EC50's) -
24 hour EC50 - 7.3 mg/l (95% CI: 6.3 - 8.8 mg/l)
48 hour EC50 - 5.1 mg/l (95% CI: 4.4 - 6.0 mg/l).
The 48 hour NOEC was 2.2 mg/l.

Executive summary:

The acute toxicity of Mortrace MP was evaluated in daphnid, Daphnia magna under static conditionsn at 20 ± 1 °C with five concentrations of test substance (1.3, 2.2, 3.6, 6.0 and 10 mg/L), a solvent control and a dilution water control (0 mg/l). The dilution water was deionized water collected and adjusted to a hardness of 160 mg/l as CaCO3 and apH less than 8.0. Nominal concentrations of Mortrace MP were used for all calculations. No insoluble material was observed at any time during the definitive test. Exposure of daphnids, Daphnia magna to Mortrace MP resulted in the following effective concentration (EC50's) -

24 hour EC50 - 7.3 mg/l (95% CI: 6.3 - 8.8 mg/l)

48 hour EC50 - 5.1 mg/l (95% CI: 4.4 - 6.0 mg/l).

The 48 hour NOEC was 2.2 mg/l.

Description of key information

In an acute, static, toxicity study with Daphnia magna,the 48-hour EC50 value for 4-(3-(1-naphthylamino)propyl) morpholine was 5.1 mg/L based on nominal concentrations. The 95% confidence interval based on nominal concentrations was 4.4 – 6.0 mg/L. 

 

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

5.1 mg/L

Additional information

One static acute toxicity test with Daphnia magnawas available for 4-(3-(1-naphthylamino)propyl) morpholine. This study was assigned a Klimisch score of 2 based on the lack of analytical measures of test solution concentrations. The 48-hour EC50 value (based on immobility) was reported as 5.1 mg 4-(3-(1-naphthylamino)propyl) morpholine/L with a 95% confidence interval of 4.4 - 6.0 mg/L. This value was based on initial nominal concentrations. Thus, the key parameter for the acute invertebrate endpoint was the EC50 value of 5.1 mg/L.