N,N,N,2,2,6,6-heptamethylpiperidin-4-aminium chloride

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

other information

Study period:

2019-03-25 to 2019-04-11

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

adopted 2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

[2,2,6,6-tetramethyl-4-(trimethylazaniumyl)piperidin-1-yl]oxidanyl chloride

EC Number:

814-375-0

Cas Number:

67036-09-3

Molecular formula:

C12H26N2OCl

IUPAC Name:

[2,2,6,6-tetramethyl-4-(trimethylazaniumyl)piperidin-1-yl]oxidanyl chloride

Test material form:

solid

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 100, 50.0, 25.0, 12.5, 6.25 mg/L and control
- Sampling method: Samples (1mL) from all test substance concentrations and control were taken at test start and test end (48 h).
- Sample storage conditions before analysis: deep frozen. All solutions were processed at room temperature allowing enough time to equilibrate.

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: A stock solution of 100 mg/L was prepared by weighing the test substance on a weighing scoop and transfering to a flask. Test medium (Elendt M4) was added up to a volume of 1000 mL and the solution was homogenised by shaking.
Lower test concentrations were prepared by dillution of the appropriate solution.
- Controls: Test medium without test substance
- Evidence of undissolved material: The stock solution (100 mg/L) was clear and slightly orange, lower concentrations were clear and transparent.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna, water flea
- Strain/clone: Clone V
- Source: Federal Evnironment Agency, Berlin/Germany
- Age at study initiation (mean and range, SD): less than 24 h
- Stage and instar at study initiation: freshly hatched daphnids less than 24 h were used for the test
- Method of breeding: continiously bred in the laboratory.
-Feeding during test: no

ACCLIMATION
- Acclimation conditions: same
- Type and amount of food: green algae (Desmodesmus subspicatus)
- Feeding frequency: at least three times per week, ad libitum
- Method for preparation of early instars: A pipette was used to separate the young daphnids from the adults.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

140 - 250 mg/L (as CaC03), corresponding to 7.8 - 14°dH

Test temperature:

18.9-20.5°C

pH:

7.34.-7.95

Dissolved oxygen:

>= 8.3 mg/L

Nominal and measured concentrations:

nominal concentrations: 100, 50.0, 25.0, 12.5, 6.25 mg/L and control. Measured concentration were in the range of 99 to 107% in new medium and in the range of 109 to 115 in the aged medium. Therefore, the nominal concentrations were used.

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass vessl (100 mL volume)
- Type: covered with glass plate
- Material, size, headspace, fill volume: Glass vessel (100 mL volume), filled up with >= 50 mL test medium.
- Volume of solution: 50 mL
- Aeration: no
- Renewal rate of test solution: static test, no renewal
- No. of organisms per vessel: 5 per vessel
- No. of vessels per concentration (replicates): 4 replicates
- No. of vessels per control (replicates): 4 replicates
- Biomass loading rate: ~10 mL for each daphnid
- 1 additional replicate per test substance concentration without organisms for physico-chemical analysis

TEST MEDIUM / WATER PARAMETERS
Elendt M4 medium according to guideline

OTHER TEST CONDITIONS
- Adjustment of pH: not during study period, at test start the pH-value of the control was 7.34.
- Photoperiod: 16 h lgiht /8 h darkness daily


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : Immobilisation, behavioural changes at 24 h and 48 h. Test temperature and pH-values, oxygen concentration at 0 h, 24 h, 48 h

RANGE-FINDING STUDY
- Test concentrations: 100, 10, 1.0, and 0.1 mg/L
- Results used to determine the conditions for the definitive study: The result of the pretest were used to derive the test substance concentrations of the main study.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: Substance specific analytic showed stable test substance concentration in aged medium. Therefore, the effect levels are based on the nominal concentration.

Effect concentrations 2

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: Substance specific analytic showed stable test substance concentration in aged medium. Therefore, the effect levels are based on the nominal concentration.

Effect concentrations 3

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 4

Duration:

24 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

After 24 and 48 hours of exposure no immobilisation was observed in the control and up to and including the highest test item concentration of 100 mg/L. No behavioural changes could be observed during the course of the study.

The measured content of test substance was between 99 % and 107 % of nominal in the fresh samples with a mean initial concentration of 104 % of nominal. In the aged samples the measured content was between 109 % and 115 % of nominal with a mean measured concentration of 112 % of nominal. Therefore, toxicological endpoints were evaluated using the nominal concentrations.

Results with reference substance (positive control):

EC50 (24 h) between 0.6 to 2.1 mg/L

Reported statistics and error estimates:

All toxicological endpoints were evaluated using nominal concentrations. The values for EC50 could not be determined statistically. The NOEC has been based on the highest concentration at which the immobilisation is not higher than the allowed control immobilisation (≤ 10 % immobilisation).

Any other information on results incl. tables

Results of the test, 48 h values

	Nominal test item concentration [mg/L]
	Control	6.25	12.5	25.0	50.0	100
	Immobilised daphnids after 48 h
Replicate 1	0	0	0	0	0	0
Replicate 2	0	0	0	0	0	0
Replicate 3	0	0	0	0	0	0
Replicate 4	0	0	0	0	0	0
Σ	0	0	0	0	0	0
%	0	0	0	0	0	0

Determined concentration of TMA-TEMPO

Test item Sampling TMA-TEMPOfound nominal [mg/L] [h] [mg/L] % of nominal Control 0 fresh n.d. -   48 aged n.d. -   6.25 0 fresh 6.21 99   48 aged 7.02 112   12.5 0 fresh 13.2 106   48 aged 13.9 111   25.0 0 fresh 26.8 107   48 aged 28.5 114   50.0 0 fresh 52.6 105   48 aged 54.4 109   100 0 fresh 105.3 105   48 aged 115.4 115

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

In this study the control immobilisation was 0 %. The dissolved oxygen concentration at the end of the test was ≥ 8.3 mg/L.

Conclusions:

After 24 and 48 hours of exposure no immobilisation was observed in the control and up to and including the highest test item concentration of 100 mg/L. The EC50 (48 h) was supposed to be > 100 mg/L (nominal). The corresponding NOEC (48 h) was 100 mg/L (nominal).