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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:
other: see 'Remark'
Remarks:
The study was conducted according to an internationally recognised method, and under GLP. Deviations were reported. In the opinion of the Study Director, the above changes did not adversely affect the validity of the study. The substance is adequately characterised. Therefore full validation applies.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2010

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Deviations:
yes
Remarks:
1.M4 mineral medium was used instead of ISO 6341 reconstituted water. 2.The range-finding test involved 2 replicate units for each test item treatment and for the controls instead of one.
Principles of method if other than guideline:
The study was conducted according to the approved study plan with the following changes:
1. M4 mineral medium was used instead of ISO 6341 reconstituted water.
2. The range-finding test involved 2 replicate units for each test item treatment and for the controls instead of one.
In the opinion of the Study Director, the above changes did not adversely affect the validity of the study.
GLP compliance:
yes (incl. QA statement)

Test material

Constituent 1
Chemical structure
Reference substance name:
6,8-dimethylnon-7-enal
EC Number:
486-670-9
Cas Number:
899810-84-5
Molecular formula:
C11H20O
IUPAC Name:
6,8-dimethylnon-7-enal
Test material form:
other: Liquid
Details on test material:
The batch number was reported as 862036.
Percent purity was certified as 97.79% .
It was stored at room temperature protected from direct sun light.

Sampling and analysis

Analytical monitoring:
yes

Test solutions

Details on test solutions:
The M4 mineral medium was used instead of ISO 6341 reconstituted water (See deviation No.1 from the study plan). The mineral medium was freshly reconstituted from analytical water and aliquot samples of mineral stock solutions.
The treatment solutions were prepared in acetone.
Range-finding test: The test concentrations were set at 100% of the nominal values and were not further adjusted during the test period.
Definitive test: The test item concentrations were set at 120% of the nominal values using 50 µL for each treatment solution, resulting in 1.2, 2.1, 3.5, 5.9 and 10.0 mg/L for the 1.0, 1.7, 2.9, 4.9 and 8.3 mg/L test item treatments (nominal values), respectively. The test solutions were renewed after 24 h of testing. The daphnids were transferred to new test tubes filled with the new test solutions, and the controls (water and solvent) were transferred similarly.

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
Origin: the strain was received from a commercial breeder and regularly sub-cultured at the Phytosafe site. Living cells of the green algae Desmodesmus subspicatus were provided as food.
Adult females were transferred in a new volume of water on the day before the start of the test. Young daphnids produced within 24 hours were used for the tests.
Daphnids were not fed during the exposure period.

Study design

Test type:
semi-static
Total exposure duration:
48 h

Test conditions

Test temperature:
Temperature was continuously controlled using a calibrated thermo-recorder. The temperature conditions were maintained at 20.0 ± 1.0°C.
pH:
Dissolved oxygen and pH were measured at the start and end of the test in the controls and in the highest test substance concentration, at least (definitive test only).
pH
Initial Final
Water control 8.04 8.47
Solvent control 8.07 8.55
Noreenal
1.0 mg/L 8.05 8.57
1.7 mg/L 8.11 8.59
2.9 mg/L 8.13 8.69
4.9 mg/L 8.14 8.71
8.3 mg/L 8.14 8.76
Dissolved oxygen:
Dissolved oxygen and pH were measured at the start and end of the test in the controls and in the highest test substance concentration, at least (definitive test only).
Dissolved O2, mg/L
Initial Final
Water control 8.5 7.7
Solvent control 8.5 6.8
Noreenal
1.0 mg/L 8.5 7.2
1.7 mg/L 8.5 7.2
2.9 mg/L 8.5 7.2
4.9 mg/L 8.5 6.9
8.3 mg/L 8.5 7.1
Nominal and measured concentrations:
NOMINAL TEST CONCENTRATIONS: Range-finding test: 0.01 – 0.1 – 1.0 – 10.0 and 100.1 mg/L
Definitive test: 1.01 – 1.71 – 2.90 – 4.92 and 8.34 mg/L

Measured Nominal concentrations mg/L
concentrations 1.01 1.71 2.90 4.92 8.34
Test initiation (To) 1.22 1.97 3.018 5.21 8.97
% nominal value 120.8 % 114.9 % 103.7 % 105.8 % 107.6 %
To+24h, Old medium 0.83 1.38 2.83 4.85 8.00
% nominal value 82.4 % 80.8 % 97.5 % 98.5 % 95.9 %
To+24h, New medium 1.19 1.98 3.35 5.42 9.27
% nominal value 118.2 % 115.9 % 115.4 % 110.1 % 111.1 %
End of test 1.15 1.92 3.19 5.38 9.10
% nominal value 113.6 % 112.3 % 109.9 % 109.3 % 109.1 %

Reference substance (positive control):
yes
Remarks:
Potassium dichromate, CAS No 7778-50-9, AnalaR, Prolabo Ref. 26784.231, batch No 07J050002.

Results and discussion

Effect concentrationsopen allclose all
Duration:
24 h
Dose descriptor:
EC50
Effect conc.:
5.4 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Duration:
24 h
Dose descriptor:
EC50
Effect conc.:
> 3.1 - < 9.6 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: 95% confidence intervals
Duration:
24 h
Dose descriptor:
NOEC
Effect conc.:
2.9 mg/L
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
2.5 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
> 1.4 - < 4.3 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: 95% confidence intervals
Duration:
48 h
Dose descriptor:
NOEC
Effect conc.:
1 mg/L
Details on results:
The daphnids were immobilized at both 10.0 and 100.1 mg/L test item treatments.
No significant immobilization was observed for the three lowest test item treatments.
The definitive test was performed with treatment concentrations ranging between approximately 1.0 and 10.0 mg/L.

RANGE-FINDING TEST
% immobilization
24 h 48 h
Water control 0 0 0 0
Solvent control 0 0 0 0
Test 0.01 mg/L 0 0 20 0
Test 0.1 mg/L 0 0 0 0
Test 1.0 mg/L 0 0 0 0
Test 10.0 mg/L 100 80 100 100
Test 100.1 mg/L 100 100 100 100

5.2.1. Percentage immobilization

% immobilization after 24 h % immobilization after 48 h
Rep 1 Rep2 Rep 3 Rep 4 Rep 1 Rep2 Rep 3 Rep 4
Water control 0 0 0 0 0 0 0 0
Solvent control 0 0 0 0 0 0 0 0
Noreenal
1.0 mg/L 20 0 0 0 20 0 0 0
1.7 mg/L 0 0 20 0 40 20 20 20
2.9 mg/L 20 20 0 0 40 80 40 60
4.9 mg/L 40 40 20 60 100 100 60 100
8.3 mg/L 40 80 100 80 60 100 100 100

Results with reference substance (positive control):
A – Percentage immobilization after 24 h of testing
% immobilization after 24 h
Rep 1 Rep2 Rep 3 Rep 4
Dichromate 0.6 mg/L 0 20 20 0
Dichromate 1.0 mg/L 60 60 40 20
Dichromate 1.7 mg/L 60 80 80 60

B – NOEC determination
Potassium dichromate
24 h
Dichromate 0.6 mg/L F = 3.00
Dichromate 1.0 mg/L F = 22.09
Dichromate 1.7 mg/L F = 147.00
NOEC 0.6 mg/L

C – EC50 calculation
After 24 h of testing
Lowest treatment group 0.6 mg/L
Highest treatment group 1.7 mg/L
Regression slope 129.7
Regression constant 40.6
Coefficient of correlation r = 0.79
EC50, mg/L 1.14
95% confidence level 0.68 – 1.91


D – Results
EC50-24h =1.14 mg/L
95%-confidence intervals = 0.68 – 1.91 mg/L
Reported statistics and error estimates:
NOEC: An F-variance analysis at a 5% confidence level served to determine any significant difference between the mean percentage immobilization in the treatment and control groups.
EC50: Percentage immobilization was plotted against the log of the Noreenal concentration in the test solutions. A regression analysis was used to calculate EC50 values (24 h and 48 h) and their related 95% confidence intervals.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The tests were considered as valid:
- Immobilization was less than 10 % in the control tubes,
- The dissolved oxygen concentration exceeded 75 % in the control and test vessels, and was therefore greater than 6.75 mg/L on the basis of 9 mg/L as the saturation value,
- The test item concentrations were satisfactorily maintained between 80-120% the nominal values over the test period.

Executive summary:

 

Phytosafe Study Number:

10-42-029-ES

Study:

Daphnia sp., Acute immobilization test with Noreenal (OECD 202, April 2004)

Test item:

Noreenal

Batch No. 862036

Nominal test concentrations:

Range-finding test:– 0.1 – 1.0 – 10.0 and 100.1 mg/L

Definitive test:– 1.71 – 2.90 – 4.92 andmg/L

Test dates:

September 7 to

Length of test:

48-hour exposure period

 

Test organisms

Daphnia magna

Source

Phytosafe s.a.r.l. 2,rue Marx Dormoy. 64000 PAU. France

Age

Less than 24 hours at test initiation

Control

Water control + solvent control

Toxic standard

Potassium dichromate (EC50-24 h between 0.6 and 1.7 mg/L)

 

Results

Range-finding test

Definitive test

NOEC-24 h

1.0 mg/L

2.9 mg/L

EC50-24 h

[95% confidence interval]

Between 1.0 and 10.0 mg/L

5.4 mg/L

[3.1 – 9.6] mg/L

NOEC-48 h

1.0 mg/L

1.01 mg/L

EC50-48 h

[95% confidence interval]

Between 1.0 and 10.0 mg/L

2.5 mg/L

[1.4 – 4.3] mg/L

Recovery of the substance at the end of test

 

81 - 121 %