2,2,6,6-tetramethylpiperidin-4-ol

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP-guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

Measured by gas chromatography at start and end of the test.

Vehicle:

no

Test organisms (species):

Daphnia magna

Details on test organisms:

- Source, supplier, any pre-treatment, breeding method: Supplied by NIES (Japan).
- Age at study initiation: Juveniles within 24h old.
- Control group: Yes.

Test type:

static

Water media type:

freshwater

Total exposure duration:

48 h

Hardness:

228 mg/L CaCO3

Test temperature:

20 ± 1 °C (measured: 20.0 - 20.5 °C)

pH:

7.4 - 10.0

Dissolved oxygen:

7.9 - 8.7 mg/L

Nominal and measured concentrations:

Nominal: 0, 10.6, 19.1, 34.3, 61.7, 111.1and 200.0 mg/L
Measured at test start: < 0.2, 11.3, 19.3, 35.6, 63.7, 119.7 and 222.7 mg/L
Measured at test end: < 0.2, 10.6, 18.2, 33.5, 59.5, 104.2 and 184.8 mg/L

Details on test conditions:

Test conditions
- Stock solutions preparation and stability: No solvent used. Test chemical was diluted to 0.3 wt.% with diluting water (Elendt M4) and it was diluted with the dilution water for testing.
- Exposure vessel type: 100 ml test solution in a 100 ml glass beaker; 4 beakers per treatment.
- Dilution water source: Dechlorinated tap water
- Lighting: room light, 16h:8h light-darkness cycle
- Feeding: Chlorella vulgaris, 0.1 - 0.2 mgC/day/individual
– Element (unit) basis: Mean cumulative numbers of juveniles produced per adult (immobilisation)
– Test design: Number of replicates = 4; individuals per replicate = 5
– Method of calculating mean measured concentrations: geometric mean.
– Exposure period: 48 h.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

100.1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

61.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Results with reference substance (positive control):

Potassium dichromate: 48 h-EC50 = 0.87 mg/L

– Analytical monitoring: By GC analysis.

101.0 - 111.4 % of the nominal concentration at preparation;

92.4 - 100.0 % of the nominal concentration at preparation (after 48 hours exposure).

Validity criteria fulfilled:

yes

Conclusions:

Due to high water solubility of the substance, the results were expressed base on the geometric mean values of the nominal concentration. The determined 24 hr-EC50 and 48 hr-EC50 values were 130.1 mg/L and 100.0 mg/L, respectively. The NOECi value of 48 hr was 61.7 mg/L. Experimental designs and results were well documented and prescribed conditions in the guideline were well satisfied.

Description of key information

The EC50 (48h) value for immobilisation derived from the key study is 100.1 mg/L. The effect concnetration is based on nominal concnetration as the concentration was within 80-120% of the analytical measured concentration.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

100.1 mg/L