Registration Dossier

Ecotoxicological information

Short-term toxicity to aquatic invertebrates

Currently viewing:

Administrative data

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 17 July, 1990 to 19 July, 1990
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study with acceptable restrictions
Remarks:
No analytical measurement was performed.
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Qualifier:
according to
Guideline:
EU Method C.2 (Acute Toxicity for Daphnia)
Version / remarks:
as published in 84/449/EEC
GLP compliance:
yes
Analytical monitoring:
no
Vehicle:
yes
Details on test solutions:
The test sample was prepared by direct dissolution in water. 1.0 g of the test substance was dissolved in water and the volume adjusted to 1 L. This stock solution was then diluted to give a 0.10 mg/L stock solution from which serial dilutions were made to give the test series.

The test substance was known to absorb to glassware and so saturation of the absorption sites was achieved by soaking the test vessels overnight prior to the start of the test with the test solutions. At 0 h the test vessels were emptied, rinsed with the solution to be tested and then refined with the fresh test solution.
Test organisms (species):
Daphnia magna
Details on test organisms:
TEST ORGANISM
- Source: Laboratory culture originating from a strain supplied by I.R.C.H.A., France.
- Culture: At 21˚C in polypropylene vessels containing 2 L of dechlorinated and aged tap water. Cultures were fed daily with a mixture of fry fish food (liquifry) and a suspension of mixed algae (predominantly Chlorella spp.). Culture conditions ensure that reproduction is by parthenogenesis.
- Selection: Gravid adults were isolated 24 h prior to initiation of the test. Young daphnids produced overnight were used for testing.
Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
48 h
Post exposure observation period:
No
Hardness:
50 mg/L of CaCO3
Test temperature:
21 ± 1˚C
pH:
7.1-7.2
Dissolved oxygen:
8.3-8.6 mg O2/L
Nominal and measured concentrations:
Nominal concentrations: 0.0010, 0.0018, 0.0032, 0.0056, 0.010, 0.018, 0.032, 0.056 and 0.10 mg/L
Details on test conditions:
TEST SYSTEM:
- Test water: Dechlorinated (with sodium thiosulphate) and aged laboratory tap water. Total hardness approximately 50 mg/L as CaC03.
- No. of organisms per vessel: 10 per replicate
- No. of vessels per concentration (replicates): Two

EXPOSURE CONDITIONS:
- Test vessels: Glass beakers each containing 200 mL test solution
- Experimental design: 9 test concentrations plus one control, each in duplicate. 20 animals per concentration
- Method of initiation: Daphnia were placed in the test solutions after addition of the test substance
- Loading: 20 mL test solution per organism
- Photo-period: 16h light: 8h dark
- Aeration: None
- Medium renewal: None

CRITERIA OF EFFECT: Daphnia were considered to be immobilised if they were unable to swim for approximately 15 sec after gentle agitation.
Duration:
24 h
Dose descriptor:
EC50
Effect conc.:
0.016 mg/L
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
mobility
Remarks on result:
other: (95% CL = 0.013-0.021 mg a.i./L)
Key result
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
0.009 mg/L
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
mobility
Remarks on result:
other: (95% CL = 0.0072-0.012 mg a.i./L)
Duration:
24 h
Dose descriptor:
NOEC
Effect conc.:
0.01 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: (i.e., equivalent to 0.0047 mg a.i./L)
Key result
Duration:
48 h
Dose descriptor:
NOEC
Effect conc.:
0.006 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: (i.e., equivalent to 0.0026 mg a.i./L)

For result tables and figures, kindly refer to the attached background material section of the IUCLID.

Validity criteria fulfilled:
yes
Conclusions:
Under the study conditions, the 48 h EC50 and NOEC were 0.0091 and 0.0026 mg a.i./L, respectively.
Executive summary:

A study was conducted to determine the acute toxicity in Daphnia magna exposed to the test substance, C16-18 TMAC (46.5% active), according to the OECD Guideline 202, under static conditions. Daphnia magna (10 per group) were exposed to the test substance at nominal concentrations of 0.0010, 0.0018, 0.0032, 0.0056, 0.010, 0.018, 0.032, 0.056 and 0.10 mg/L for 48 h and immobilisation was determined. The 48 h EC50 and 95% confidence interval were calculated as 0.0091 and 0.0072-0.012 mg a.i./L. The 48 h NOEC was 0.0026 mg a.i./L. No analytical determination of the test substance was performed. Under the test conditions, the 48 hour EC50 and NOEC were 0.0091 and 0.0026 mg a.i./L (nominal), respectively (Handley and Wetton, 1990).

Description of key information

The 48 h EC50 value of the test substance for toxicity aquatic invertebrates, which was determined at 0.0091 mg a.i./L (nominal) has been considered further for hazard/risk assessment.

Key value for chemical safety assessment

EC50/LC50 for freshwater invertebrates:
9.1 µg/L

Additional information

A study was conducted to determine the acute toxicity in Daphnia magna exposed to the test substance, C16-18 TMAC (46.5% active), according to the OECD Guideline 202, under static conditions. Daphnia magna (10 per group) were exposed to the test substance at nominal concentrations of 0.0010, 0.0018, 0.0032, 0.0056, 0.010, 0.018, 0.032, 0.056 and 0.10 mg/L for 48 h and immobilisation was determined. The 48 h EC50 and 95% confidence interval were calculated as 0.0091 and 0.0072-0.012 mg a.i./L. The 48 h NOEC was 0.0026 mg a.i./L. No analytical determination of the test substance was performed. Under the test conditions, the 48 hour EC50 and NOEC were 0.0091 and 0.0026 mg a.i./L (nominal), respectively (Handley and Wetton, 1990).