Registration Dossier

Ecotoxicological information

Short-term toxicity to aquatic invertebrates

Administrative data

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:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2017
Report Date:
2017

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
liquid

Test solutions

Vehicle:
no

Test organisms

Test organisms (species):
Daphnia magna

Study design

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
48 h

Test conditions

Test temperature:
20 +/- 1°C
pH:
7.8 - 8.1
Nominal and measured concentrations:
100, 55.6, 30.9, 17.1, 9.53 mg/L
Details on test conditions:
TEST SYSTEM
- Test vessel:
- Type: closed without headspace
- Aeration: no
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4

OTHER TEST CONDITIONS
- Adjustment of pH: yes
- Photoperiod: 16h light / 8h dark
- Light intensity: room light

Results and discussion

Effect concentrationsopen allclose all
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
Remarks on result:
other: pH adjusted to 7.8 - 8.1
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
31.3 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: pH unadjusted 9.7
Details on results:
Because the pH in the highest test concentration exceeded 9.0 in the preliminary study, 100 mg/L adjusted to the pH of dilution water was added to confirm whether the effect in a test where pH was not adjusted was caused by the test item or by the high pH. As a result, the 48-hour EC50 in pH unadjusted exposure test was determined to be 31.3 mg/L (95% confidence limits: 26.4-37.6 mg/L). In contrast, no adverse effect was found in the test where pH was adjusted.
From the results above, it was concluded that pH had an adverse acute effect on the test organisms.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The 24-hour and 48-hour EC50 of the test item for Daphnia magna in pH adjusted exposure test were both > 100 mg/L.