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

Short-term toxicity to aquatic invertebrates

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:

2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Residue analysis was not performed on actual test concentrations. This does not invalidate the overall significance of the study.

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation 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:
- Sampling method: at 0 and 48 hours
- Sample storage conditions before analysis:

Vehicle:

no

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna STRAUS
- Strain/clone: no data
- Source: Animals bred at the testing facility, originally derived from the German Federal Environmental Ageny (Umweltbundesamt)
- Age of parental stock: Neonates 2 - 24 hrs old
- Feeding during test: no

ACCLIMATION
- Acclimation conditions: In Elendt M4 medium; 20 +/- 1 °C, 12:12 hrs light:dark cycle
- Type and amount of food: Schenedesmus (current name: Desmodesmus) subspicatus green algae, no data about amount and frequency

Test type:

static

Water media type:

freshwater

Total exposure duration:

48 h

Test temperature:

20 +/- 1 °C

pH:

7.2 – 7.6 (both tests)

Dissolved oxygen:

8.2 – 8.4 mg/L (first test), 8.4 – 10 mg/L (second test)

Nominal and measured concentrations:

Initial concentrations : First test: 3, 4.2, 5.9, 8.2, 11.5 µg/L, plus control, Second test: 11.5, 16.1, 22.5 µg/L, plus control
Actual concentrations: Nominal test concentrations were around or below the quantification limit (10 µg/L); test substance stability was therefore tested seperately at a concentration of 500 µg/L (41% after 0 h, 41% after 24 h, 37% after 48 h). It reveals that these results are also not reliable, due to unknown reasons.

Details on test conditions:

TEST SYSTEM
- Test vessel: 20 mL
- Type: open
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- Biomass loading rate: 4 mL/animal

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Reconstituted medium as given in guideline OECD 202
- Culture medium different from test medium: Yes, daphnids were reared in Elendt M4 medium (as given in guideline OECD 202)

EFFECT PARAMETERS MEASURED: Immobility, sampled at 24 and 48 hours

Reference substance (positive control):

not required

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 0.008 - < 0.011 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

0.006 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

0.022 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

- Mortality of control: No immobilisation, 100 % survival

  Effect data (Immobilisation):

Test substance Concentration (nominal) [mg/l]	ImmobileDaphnia
	Number		Percentage		O2 [mg/l] 48 h	pH   48 h
	24 h	48 h	24 h	48 h
Control (1)	0	0	0	0	8.3	7.5
0.0115 (1)	3	11	15	55	8.2	7.4
0.0082 (1)	3	4	15	20	8.3	7.4
0.0059 (1)	0	0	0	0	8.3	7.4
0.0042 (1)	0	0	0	0	8.3	7.4
0.003 (1)	0	0	0	0	8.3	7.4
Control (2)	0	0	0	0	8.7	7.2
0.0225 (2)	3	20	15	100	8.4	7.2
0.0161 (2)	1	17	5	85	8.4	7.2
0.0115 (2)	2	12	10	60	8.6	7.2

(1)    = 1^st test, (2) = 2^nd test

 

The 24h-EC values were not determinable

Validity criteria fulfilled:

yes

Conclusions:

The test results indicate that octenidine dihydrochloride is acutely very toxic towards Daphnia magna.

Executive summary:

The test was performed according to the OECD guideline 202. The water flea Daphnia magna STRAUS (Crustacea: Cladocera) was used as the test organism on acute toxicity of Octenidine dihydrochloride towards invertebrates.

In the first test animals were exposed to five concentrations of Octenidine dihydrochloride, ranging from 3.2 to 11.5 µg/L and a control group. All concentrations were tested using 4 replicate treatments with 5 animals each. The test was performed at 20 °C and in complete darkness in a reconstitued medium according to OECD guideline 202. Immobili­sation was assessed at 24 and 48 hours, physico-chemical water parameters were measured at 0 and 48 hours.

Because less than 100 % immobility was yielded in the highest concentration, a second test was run under the same conditions, employing concentrations of 11.5, 16.1 and 22.5 µg/L and a control group.

Actual concentrations of Octenidine dihydrochloride were assayed by HPLC after 0, 24 and 48 hours in separate vessels but results were unreliable.

Octenidine dihydrochloride was found to be acutely very toxic towards Daphnia magna. Residue analysis of test concentrations was impossible because the HPLC method was not sufficiently sensitive. Also, results from a seperate test at a higher substance concentration in a blank vessel were not reliable.

Due to unreliable results of the octenidine dihydrochloride analyses, measured values are estimated by applying the mean percent recovery rates obtained from the test on D. magna reproduction. A geometric mean of initial (94.3% at 0 h) and final (51.3% at 48 h) percent recovery values, as required by OECD 202, was applied as follows:

(94.3 · 51.3)^½= 69.55

Thus, nominal values are divided by 69.55% to give the measured average values.

Except stability of the test substance concentration all validity criteria according to the test guideline OECD 202 are met in both tests performed during this study.

EC0	0.0042 mg/L (measured average)
EC50	between 0.0058 and 0.008 mg/L (measured average) We propose the arithmetic mean to be used as EC50 EC50= 0.0068 mg/L (measured average)
EC100	0.0156 mg/L(measured average)

Description of key information

Acute toxicity towards invertebrates was tested with the water flea Daphnia magna, and the EC₅₀ was established at approximately 0.007 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

0.007 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.