Registration Dossier

Diss Factsheets

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 February 11, 1998 to February 20, 1998
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
test procedure in accordance with national standard methods
Remarks:
Study conducted according to ISO/CD 14669 and the PARCOM ring test protocol in compliance with GLP
Qualifier:
according to guideline
Guideline:
other: ISO/CD 14669 and the PARCOM ring test protocol
Deviations:
yes
Remarks:
pH and O2 measurement frequency slightly altered
GLP compliance:
yes
Analytical monitoring:
no
Details on sampling:
Sampling not performed
Vehicle:
no
Details on test solutions:
- Dilution water used was natural seawater from the Eastern Scheldt. This water was checked for contaminants (volatile organics, organochlorine compounds and oil) before use.
- The water was also filtered and recirculated over a carbon filter before use. 0.0030 g of the test substance was dissolved directly in 3L of diluted natural seawater. From this 1mg/L stock the test concentrations were made.
- The substance was dispersable in water
Test organisms (species):
other: aquatic crustacea: Acartia tonsa
Details on test organisms:
- The test animal was the marine crustacean Acartia tonsa cultured in the laboratory under standard conditions.
- The animals used in the test were copepodites (subadults) between 6 and 8 days old.
Test type:
static
Water media type:
saltwater
Limit test:
no
Total exposure duration:
48 h
Post exposure observation period:
No, during the test only.
Hardness:
No data
Test temperature:
The temperature as measured in the control medium was 19.6 ⁰C at the start of the test and 19.4 ⁰C at the end
pH:
8.0-8.2
Dissolved oxygen:
7.3 - 7.7 mgO2/l
Salinity:
(32% diluted to) 29%
Nominal and measured concentrations:
Nominal: 0, 0.056, 0.10, 0.18, 0.32, 0.56, 1.0 mg/L

Details on test conditions:
TEST SYSTEM
- Test vessel: 10 small glass vessels
- Type (delete if not applicable): Closed
- No. of organisms per vessel: 1
- Material, size, headspace, fill volume: 10 mL

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Sea water
- Diluted seawater at 29% salinity was used in the control

OTHER TEST CONDITIONS
- Photoperiod: 16 h light: 8 h dark


Reference substance (positive control):
no
Key result
Duration:
24 h
Dose descriptor:
LC50
Effect conc.:
ca. 0.397 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mortality
Remarks on result:
other: 0.318-0.495 mg/L
Remarks:
equivalent to 0.298 mg a.i./L
Key result
Duration:
48 h
Dose descriptor:
LC50
Effect conc.:
ca. 0.295 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mortality
Remarks on result:
other: 0.237-0.367 mg/L
Remarks:
equivalent to 0.221 mg a.i./L
Key result
Duration:
48 h
Dose descriptor:
NOEC
Effect conc.:
ca. 0.1 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
other: mortality and behaviour
Remarks on result:
other: equivalent to 0.075 mg a.i./L
Details on results:
- Mortality and condition have been recorded in the test. Immobile, sluggish or drugged animals were not observed and no mortality in the controls.
- The LC50 and NOEC 48h were 0.295 and 0.10 mg/L respectively.
Results with reference substance (positive control):
Not applicable
Reported statistics and error estimates:
Maximum likelihood estimates of the LC50 values were calculated assuming a log-logistic dose-effect relationship. Likelihood-ratio confidence intervals were derived from the confidence intervals.

Results

Table 1 Summary of the data on survival in the acute toxicity test with Acartia tonsa exposed to test material

Time

(h)

Nominal concentration of test substance (mg/L)

0

0.056

0.10

0.18

0.32

0.56

1.0

0

10

10

10

10

10

10

10

24

10

10

10

10

8

1

0

48

10

10

10

8

6

0

0

Validity criteria fulfilled:
yes
Conclusions:
Under the study conditions, the 24 h LC50, 48 h LC50 and 48 h NOEC of test substance to Acartia tonsa in diluted natural seawater were determined to be 0.397, 0.295 and 0.10 mg/L (equivalent to 0.298, 0.221 and 0.075 mg a.i./L), respectively.
Executive summary:

A study was conducted to determine the acute toxicity of the test substance, C12-18 DAQ (75% active) to Acartia tonsa (Copepod: Crustacea), according to the draft International Standard ISO/CD 14669 and a PARCOM ring-test protocol in compliance with GLP. Ten individual replicate scintillation vials, each containing one Acartia tonsa were exposed to nominal concentrations of 0.056, 0.10, 0.18, 0.32, 0.56 and 1.0 mg/L for 48 h under static conditions. No chemical analyses of the test concentrations were performed during the test and all concentrations mentioned are nominal concentrations of the test substance. Maximum likelihood estimates of the LC50 values were calculated assuming a log-logistic dose-effect relationship. The results of the tests based on nominal concentrations were 24 h LC50 0.397 (0.318-0.495) mg/L, 48 h LC50 0.295 (0.237 -0.367) mg/L, 48 h NOEC (mortality and behaviour) 0.10 mg/L. At the start of the test all test media were clear and colorless (visually assessed). No mortality was observed among the control population following a 48 h exposure. Under the study conditions, the 48 h LC50 and NOEC of the test substance to Acartia tonsa in diluted natural seawater were determined to be 0.295 and 0.10 mg/L (equivalent to 0.221 and 0.075 mg a.i./L), respectively (Schoonmade, 1998).

Description of key information

Based on the study result, the 48 h LC50 of the test substance to Acartia tonsa in diluted natural seawater was determined to be 0.221 mg a.i./L (nominal).

Key value for chemical safety assessment

Marine water invertebrates

Marine water invertebrates
Effect concentration:
0.22 mg/L

Additional information

A study was conducted to determine the acute toxicity of the test substance, C12-18 DAQ (75% active) to Acartia tonsa (Copepod: Crustacea), according to the draft International Standard ISO/CD 14669 and a PARCOM ring-test protocol in compliance with GLP. Ten individual replicate scintillation vials, each containing one Acartia tonsa were exposed to nominal concentrations of 0.056, 0.10, 0.18, 0.32, 0.56 and 1.0 mg/L for 48 h under static conditions. No chemical analyses of the test concentrations were performed during the test and all concentrations mentioned are nominal concentrations of the test substance. Maximum likelihood estimates of the LC50 values were calculated assuming a log-logistic dose-effect relationship. The results of the tests based on nominal concentrations were 24 h LC50 0.397 (0.318-0.495) mg/L, 48 h LC50 0.295 (0.237 -0.367) mg/L, 48 h NOEC (mortality and behaviour) 0.10 mg/L. At the start of the test all test media were clear and colorless (visually assessed). No mortality was observed among the control population following a 48 h exposure. Under the study conditions, the 48 h LC50 and NOEC of the test substance to Acartia tonsa in diluted natural seawater were determined to be 0.295 and 0.10 mg/L (equivalent to 0.221 and 0.075 mg a.i./L), respectively (Schoonmade, 1998).