N,N-bis(1-methylethyl)formamide

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:

From February 02, 2021 to February 08, 2021

Reliability:

1 (reliable without restriction)

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

13th April 2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Batch number: M-O303190723301F
Purity: 99.68%

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 100 mg/L
- Sampling method: Samples were taken for analysis from the freshly prepared solutions at 0 hour and the old solutions at 48 hours.
- Sample storage conditions before analysis:

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: 0.0501 g test item was weighed and dissolved in 500 mL of test water directly. After the test item was dissolved completely, the solution of 100 mg/L was used for exposure.
- Controls: dilution water (without test item)
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): water

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain/clone:
- Justification for species other than prescribed by test guideline:
- Age at study initiation (mean and range, SD): less than 24 hours old and not the first brood progeny.
- Source: Daphnia of stock culture was originally obtained from Applied Chemistry Department Pesticide Environmental Evaluation Laboratory of China Agricultural University.

ACCLIMATION
- Acclimation period: 24 hours
- Acclimation conditions (same as test or not): same
- Health during acclimation (any mortality observed): showing no signs of stress such as high mortality, presence of males and ephippia, delay in the production of the first brood, discolored animals

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

140 to 250 mg/L (as CaCO3)

Test temperature:

18~22oC

pH:

6.0 to 8.5 pH units

Dissolved oxygen:

not less than 3 mg/L during the test period

Nominal and measured concentrations:

100 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 200 mL glass beakers
- Type (delete if not applicable): open / closed
- Material, size, headspace, fill volume:
- Volume of solution: 100 mL per vessel
- Aeration: Before usage, the water was aerated for more than 24 hours to attain dissolved oxygen saturation.
- Type of flow-through (e.g. peristaltic or proportional diluter):
- Renewal rate of test solution (frequency/flow rate): no
- No. of organisms per vessel: 5 daphnia
- No. of vessels per concentration (replicates): 4 replicates
- No. of vessels per control (replicates): 4 replicates
- No. of vessels per vehicle control (replicates):
- Biomass loading rate:

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: the dilution water was tap water after being treated with Aquapro Pure Water System
- Total organic carbon: < 2 mg/L
- Intervals of water quality measurement: in all fresh and old media for both control and test group.

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 hr light: 8 hr dark
- Light intensity:

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
Observation intervals: 24（±1） and 48（±1）hours after exposure
Method: Each test vessel was checked for immobilized daphnids. In addition to immobility, any abnormal behavior or appearance were recorded. Those animals that are not able to swim within 15 seconds, after gentle agitation of the test vessel are considered to be immobilized (even if they can still move their antennae).

VEHICLE CONTROL PERFORMED: yes

RANGE-FINDING STUDY
- Test concentrations: 1, 10, 100 mg/L
- Results used to determine the conditions for the definitive study: During the period of 48 hours, no immobilization or any toxic signs were observed in the control group and the test groups of 1, 10 and 100 mg/L.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate as reference item was tested for EC50 as a means of assuring that the test conditions are reliable four times a year in the laboratory.

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:

During the 48-hour exposure period, no immobilization and abnormal behavior or appearance was observed in the control group and the test group of 100 mg/L.

Results with reference substance (positive control):

EC50-24 h of potassium dichromate to Daphnia magna was 1.17 mg/L, and the 95% confidence limits was 0.99 ~ 1.39 mg/L. The results met the recommended criterion in OECD Guideline No. 202: EC50-24 h of potassium dichromate is within the range of 0.6 mg/L to 2.1 mg/L.

Validity criteria fulfilled:

yes

Conclusions:

The 48-hour EC50 of the test item to Daphnia magna was greater than 100 mg/L.

Executive summary:

A Daphnia acute immobilisation test of the test item was conducted with Daphnia magna over a 48-hour exposure period, according to OECD Guideline 202 under GLP.

According to the results of test and based on the nominal concentration, the 48-hour EC₅₀ of the test item to Daphnia magna was greater than 100 mg/L.

Description of key information

A Daphnia acute immobilisation test of the test item was conducted with Daphnia magna over a 48-hour exposure period, according to OECD Guideline 202 under GLP.

According to the results of test and based on the nominal concentration, the 48-hour EC₅₀ of the test item to Daphnia magna was greater than 100 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

> 100 mg/L