N,N'-(decane-1,10-diyldi-1(4H)-pyridyl-4-ylidene)bis(octylammonium) dichloride

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Analytical monitoring in the test setups with fish delivered unclear results. This does not invalidate the overall significance of the results.

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 104663
- Purity: 98.9%

OTHER SPECIFICS:
White powder
Test substance is not volatile

Analytical monitoring:

yes

Details on sampling:

- Concentrations: Samples from vessels with nominal concentrations of 1.05, 0.32 and 0.1 mg/L test substance were taken at 0, 24, 48, 72 and 96 hours

Vehicle:

no

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Zebrafish
- Source: Fischzucht Krämers, D-42781 Haan, Germany
- Length at study initiation: 2 +/- 1 cm

ACCLIMATION
- Acclimation period: Acclimation to the test conditions eight days prior to test start, daily feeding until one day before test start
- Type and amount of food during acclimation: Tetra AniMin, Tetra Werke, Melle, Germany
- Feeding frequency during acclimation: 5 times / week

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

No data

Test temperature:

20.5 – 21.3 °C

pH:

7.2 – 7.6

Dissolved oxygen:

7.9 – 8.8 mg/L

Conductivity:

No data

Nominal and measured concentrations:

Initial concentrations: Control, 0.1, 0.18, 0.32, 0.58, 1.05 mg/L
Actual concentrations: Two measurements were performed to monitor the test substance concentration in the test aquaria. The first measurement was performed in parallel to the test, but gave inconsistent results with far too high recoveries. A second measurement was then performed on frozen samples but the results appear also unreliable.
Analyses from a blank aquarium (without fish) revealed time-dependent depletion to 47% of the initial value after 96 h. These results are in accordance with a fully reliable analytical monitoring procedure.

Details on test conditions:

TEST SYSTEM
- Test vessel: 10 L-aquaria, filled with 7 L medium
- Aeration: No data
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- Biomass loading rate: 0.63 g fish /L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Reconstituted water as given in guideline OECD 203
- Culture medium different from test medium: Yes, flow-through system using tap water

OTHER TEST CONDITIONS
- Adjustment of pH: No
- Photoperiod: 12:12 hours light:dark cycle
- Light intensity: No data

EFFECT PARAMETERS MEASURED:
Mortality. After 3, 24, 48, 72, and 96 hours mortality, pH and oxygen content were recorded

Reference substance (positive control):

no

Remarks:

not required by guideline

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

0.18 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

0.18 - 0.32 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

0.58 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities: In the medium dose group (0.32 mg/L) slower movements and orientation to the ground was observed after 24 and 48 hrs.
- Mortality of control: none

Reported statistics and error estimates:

Calculation of median effect concentration (EC50) after 24, 48, 72 and 96 hours, referring to nominal and measured concentrations

Validity criteria fulfilled:

yes

Conclusions:

The test results indicate that octenidine dihydrochloride is acutely toxic towards fish.

Executive summary:

The test was performed according to the OECD guideline 203 (1984).Brachidanio rerio(Zebrafish) was used as test organism.Seven fish were exposed to each of the five nominal concentrations of the test substance between 0.1 and 1.05 mg/L and to a control. The test was performed at 21 °C and 12:12 hours light: dark cycle in an artificial medium according to the guideline. Test duration was 96 hours and survival was assessed every 24 hours. pH, dissolved oxygen and test substance concentrations were measured in the same intervals.

Octenidine dihydrochloride was found to be acutely toxic towards fish. A clear concentration-response relationship can be deduced from the study results.All validity criteria according the test guideline OECD 203 are met within the study.

Analytical monitoring of the actual test concentrations in vessels with fish gave inconsistent and unsatisfactory results due to unknown reasons. Analysis of concentrations in a blank vessel without fish revealed time-dependent depletion to 47% of the initial value after 96 h. This percentage is in accordance with the results from a fully reliable analytical procedure. Subsequently, the geometric mean of the measured initial (0 h) and final percent values (96 h) is used as an average value of octenidine dihydrochloride exposition over the test duration of 96 h:

(98.0·47)^½=67.9

Mean average concentration = 67.9% of nominal concentration

The decreasing concentrations cannot be ascribed to volatility or hydrolysis, as octenidine dihydrochloride is non-volatile and stable in aequeous solution. Another possibility is adsorption to glass container walls, therefore the results from the blank vessel without fish can reliably be used as an estimate for non-biological adsorption.

LC0	0.122 mg/L (measured average) (calculation 0.18 mg/L * 0.679 =0.122 mg/L)
LC50	> 0.122 mg/L but < 0.217 mg/L (measured average) (calculation 0.18 mg/L * 0.679 = 0.122 mg/L ; 0.32 mg/L * 0.679 = 0. 217 mg/L ) We propose to be use the arithmetic mean of 0.122 mg/L and 0.217 mg/L as LC50 : LC50= 0.17 mg/L
LC100	0.394 mg/L (measured average) (calculation 0.58 mg/L * 0.679 = 0.394 mg/L)

Description of key information

In a study on the acute toxicity of octenidine dihydrochloride towards fish the LC₅₀ was determined to be between 0.122 and 0.217 mg/L (arithmetic mean = 0.17 mg/L), employing the zebrafish (Brachydanio rerio) as the test organism.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

0.17 mg/L

Additional information

Analytical monitoring of the test substance was performed during this study. However, for unknown reasons results from vessels with organisms delivered inconsistent and unreliable results. Therefore, measured concentrations refer to the results from blank vessels without organisms, which were set up in parallel to the biotests.