(Z)-4-[C11-13 (branched) alkylamino]-4-oxo-2-butenoic acid

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study with analytical monitoring

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Vehicle:

no

Details on test solutions:

PREPARATION OF TEST SOLUTION
- Since the test item is poorly soluble in water, a modification of the standard method for the preparation of aqueous media was performed with help of water accomodated fractions (WAF).
- Using this approach, aqueous media were prepared by shaking the test item with dilution water at 20 rpm for 24 hours at room temperature to ensure equilibration between the test item and the water phase.
- For each loading level, an appropriate amount of the test item was weighed out and transferred into a brown glass flask with an appropriate amount of dilution water.
- After the completion of shaking and following a 1-h settlement period, the test item phase was separated by siphon and the test organisms exposed to the clear aqueous phase, the WAF.
- Exposures are expressed in terms of the original concentrations of the test item in water at the start of the mixing period (loading levels) irrespective of the actual concentrations of the test item in the WAFs.
- All tested loading levels were visually clear throughout the exposure period.

Test organisms (species):

Daphnia magna

Details on test organisms:

- Test organism: Daphnia magna STRAUS (Clone 5)
- Origin: Institut für Wasser-, Boden- und Lufthygiene (WaBoLu)
- Breeder: Dr. U. Noack-Laboratorien
- Culturing: in glass vessels (2 - 3 L capacity) with approx. 1.8 L culture medium; at 20 +- 2°C; in an incubator; 16 h illumination; light intensity of max. 20 µE*m-2 * s-1; pH in the range of 6 to 9.
- Culture medium: Elendt M4, according to Elendt (1990), modified to a total hardness of 160 - 180 mg CaCO3/L
- Culture feeding: at least 5 times weekly ad libitum with a mix of unicellular green algae, e.g. Pseudokirchneriella subcapitata and Desmodesmus subspicatus, with an algae cell density of > 106 cells/mL.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

173 mg CaCO3/L

Test temperature:

19.9 °C

pH:

7.22 - 7.95

Dissolved oxygen:

5.60 - 8.73 mg/L

Nominal and measured concentrations:

- Nominal loadings of the test item: 6.25, 12.5, 25.0, 50.0 and 100 mg/L plus control

Details on test conditions:

TEST SYSTEM
- Test vessels: glass beakers (50 ml, nominal)
- Test volume: 20 ml
- Dilution water: same as for culture
- No. organisms / replicate: 5
- No. replicates / concentration: 4
- No. organisms / concentration: 20
- Age of daphnids at test initiation: 2 to 24 h old daphnids were used for the study

FURTHER CONDITIONS
- Illumination: diffuse light, light intensity of max. 20 µE*m-2 * s-1.
- Photoperiod: 16/8 h light/dark cycle
- Feeding: none

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

48 h

Dose descriptor:

EL50

Effect conc.:

17.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CL 12.5 - 25.0

Details on results:

- The recoveries of the test item at the end of the exposure (48 h) were in the range of 56 - 90% of the nominal values and therefore, the measured effect concentrations should be use for the hazard assessments. The recoveries however were inhomogeneously distributed. In the range of the EL50, the recovery was between 82 - 90 %. Thus, the effect concentration can be given as nominal concentration.
- The inhomogeneous recoveries may be explained by inhomogeneous distribution of the test item in the WAF.
- The recovery rates at the end of the exposure were in the same range as at the start of the exposure. Thus, the test item concentrations were successfully maintained for the duration of the test.

Results with reference substance (positive control):

EC50 (24 h) = 1.60 mg/L

Validity criteria fulfilled:

yes

Description of key information

In an acute immobilistion test with D. magna acoording to OECD TG 202, effects have been observed. The EC50 value is 17.7 mg/L. 

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

17.7 mg/L

Additional information

In the acute immobilization test with Daphnia magna the effects of the water accommodated fraction (WAF) with 5 different loadings were determined according to OECD guideline 202 [Dr. U. Noack-Laboratorien, 2013]. The experiment was conducted under static conditions over a test period of 48 h. At test termination, an EL50 of 17.7 mg/L (nominal) was determined.