3-methoxy-N,N-dimethylpropionamide

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:

31 August 2007 - 27 September 2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

2004

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: "Acute swimming immobilization test in water flea" stipulated in "Order Prescribing the Tests Relating to the New Chemical Substances" (Yaku-shoku-Hatsu No. 1121002, Heisei 15.11.13 Seikyoku No.2, Kanpoki-Hatsu No. 031121002 dated November 21, 2003)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Solubility in water: ≥ 300 g/100 g
Solubility in hexane: 50 g/100 g
Stability: stable under storage conditions

Analytical monitoring:

yes

Details on sampling:

- Frequency: at t=0 h and at t=48 h

Vehicle:

no

Details on test solutions:

- Preparation of test solutions: A required amount of test substance (corrected for purity 99.0%) was added to the dilution water, mixed, stirred and dissolved in a preparation vessel to prepare the test solution. The prepared test solution was divided into each replicate test vessel. The test solution was colourless and transparent at the start of the test and remained this way until the end of the exposure period.
- Control: dilution water without test substance (blank-control).

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain/clone: Clone A
- Source: Sheffield University, England
- Age at study initiation: < 24 hours old
- Age of parental stock (mean and range, SD): 17 days
- Feeding during test: no

ACCLIMATION
- Acclimation period: no, parent animals were cultured for over 14 days under the same conditions as used in the test
- Food during subculture period: Chlorella vulgaris, once daily, an amount corresponding to 0.1-0.2 mg C/daphnia
- Only the group that showed no mortality during the subculture period was used in the final test

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

37 mg/L

Test temperature:

19.8-20.0 °C during the exposure period

pH:

7.8-7.9 during the exposure period

Dissolved oxygen:

8.2-8.4 mg O2/L during the exposure period

Nominal and measured concentrations:

Nominal concentration: 100 mg/L
Mesured concentration: t=0: 104mg/L; t=48: 104 mg/L
The result was based on the nominal test concentration.

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 mL glass beakers, covered, fill volume approx. 100 mL
- Aeration during the test: well aerated water was used as dilution water
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Dilution water: aerated dechlorinated tap water
- Intervals of water quality measurement: dissolved oxygen concentration, pH and water temperature of the test solution were measured at the start and at the end of exposure.

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 hours light (room light)

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : mobility at t=24 h and t=48 h

RANGE-FINDING STUDY
- Test concentrations: 100 mg/L
- Results used to determine the conditions for the definitive study: yes, no effects were observed

Reference substance (positive control):

yes

Remarks:

Potassium dichromate (June 2007)

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- no immobility or other symptoms were observed in either the control group or the treatment groups.
- water quality parameters all remained within prescribed levels

Results with reference substance (positive control):

- 48 h-EC50: 0.269 mg/L
- This value was within the historical range and confirmed the validity of the test system.

Validity criteria fulfilled:

yes

Remarks:

Immobilisation or other adverse effects were not observed in the control group and dissolved oxygen concentrations were >3 mg/L during the exposure period.

Conclusions:

The 48-h EC50 of MDMPA for immobility of Daphnia magna exceeded the highest tested concentration (i.e., > 100 mg/L).

Executive summary:

In a 48 h acute toxicity study conducted according to OECD guideline 202 and GLP principles, water fleas (Daphnia magna) were exposed to the test substance under static conditions in a limit test. The exposure concentration of 100 mg/L was varified by a sufficiently validated analytical method to be 104 mg/L at t=0 and 104 mg/L at t=48, therefore the test solution was considered to be stable in test medium and the result was based on the nominal test concentration. The incidence of immobilisation was recorded at 24 and 48 hours. No immobilisation or other effects were seen during the exposure period. Therefore, the 48h-EC50 exceeded the test concentration of 100 mg/L (i.e., was >100 mg/L). The validity criteria were met and the study is considered to be valid.

Description of key information

In a 48 h acute toxicity study conducted according to OECD guideline 202 and GLP principles, water fleas (Daphnia magna) were exposed to the test substance under static conditions in a limit test. The exposure concentration of 100 mg/L was varified by a sufficiently validated analytical method to be 104 mg/L at t=0 and 104 mg/L at t=48, therefore the test solution was considered to be stable in test medium and the result was based on the nominal test concentration. The incidence of immobilisation was recorded at 24 and 48 hours. No immobilisation or other effects were seen during the exposure period. Therefore, the 48h-EC50 exceeded the test concentration of 100 mg/L (i.e., was >100 mg/L). The validity criteria were met and the study is considered to be valid.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L