1-acetyl-4-(3-dodecyl-2,5-dioxo-1-pyrrolidinyl)-2,2,6,6-tetramethylpiperidine

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:

1991-09-16 to 1991-09-20

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study with acceptable restictions, without detailed documentation; however, most relevant data given, performed compliant with GLP

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Version / remarks:

adopted 1984: 84/449/EEC C.1 (Acute toxicity for fish)

Deviations:

no

Remarks:

(limit test yet not foreseen but performed acc. to updated version adopted 1992)

GLP compliance:

yes

Analytical monitoring:

yes

Vehicle:

yes

Details on test solutions:

Solubilizing aid: methanol was used as solvent aid for preparing the stock batches of the test substance (81 mg/L).

Test organisms (species):

Leuciscus idus melanotus

Details on test organisms:

Name: Gold orf [ide]
Scientific name: Leuciscus idus melanotus HECKEL
Source: Eggers Fish Breeding Farm/Hohenwestedt
Size of the fish: 6 cm +/- 2 cm

CARE AND MAINTENANCE
The fish were kept in dechlorinated drinking water in 200 L stone ponds at 22°C ± 2°C. They were kept in a flow-through aquarium with a flow rate of approximately 20 L/h. The daily amount of feed consisted of Tetramine and was administered with the help of automatic feeders. The admistered feed was approximately 3% of the body weight. After delivery, the fish were subjected to a precautionary treatment with ZEPHIROL 1:50 000 for one hour with a subsequent quarantine (14 days). At the beginning of the study, fish behavior was normal and the test organisms were free of any obvious diseases.

Test type:

flow-through

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

15 °dH [German degrees of water hardness)

Test temperature:

20- 21 °C

pH:

Treatment group: (start) 8.1, (end) 7.6
Control: (start) 8.0, (end) 8.0
Solvent control: (start) 8.1, (end) 7.6

Dissolved oxygen:

Treatment group: 8.8 mg O2/L (start), 8.5 (24h), 6.6 (48h), 2.6 (72h), 3.1 mg O2/L (end)
Control: (start) 8.8 mg O2/L, (end) 8.3 mg O2/L
Solvent control: 8.9 mg O2/L (start), 8.7 (24h), 7.2 (48h), 2.6 (72h), 3.9 mg O2/L (end)

Nominal and measured concentrations:

Measured concentration (mg/L):
Start: 0.582
24 hours: 0.559
48 hours: 0.442
72 hours: 0.806
96 hours: 0.100

Details on test conditions:

TEST SYSTEM
Test aquariums: 45 L
Type of test: flow through, 10 L/h
Test volume: 35 L
Venting: continuous
Medium: dechlorinated drinking water
Temperature: 21 ± 1°C
Total water hardness: 15 °dH [German degrees of water hardness]
Ca/Mg ratio: 4:1
Light-dark rhythm: 16 hours photoperiod daily
Population density: 10 fish per test pond
Feeding: none
Solubilizing aid: methanol
No. of organisms per vessel: 10
No. of vessels per concentration (replicates): 1
No. of vessels per control (replicates): 1
No. of vessels per vehicle control (replicates): 1

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- mortality; after 24, 48, 72 and 96 hours

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 0.5 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: mean measured concentration at time point 0, 24, 48, 72 and 96 hours

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

>= 0.5 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: mean measured concentration at time point 0, 24, 48, 72 and 96 hours

Details on results:

MORTALITY
No fish mortality was observed.

EFFECT CONCENTRATIONS
Despite the use of a flow-through method, the concentration dropped below 80% of the initial concentration in two cases; thus, according to ECHA guidance document R.7b (section Annex to R.7.8, difficult substances) the arithmetic mean measured concentration was taken as the exposure concentration.

- Effect concentrations exceeding solubility of substance in test medium: yes

Validity criteria fulfilled:

no

Remarks:

The dissolved oxygen concentration dropped below 60% saturation after 72 h in solvent control and treatment. Because no mortality was observed this does not put into question the outcome of the study.

Conclusions:

The test item did not cause any fish mortality at the arithmetic mean measured concentration of 0.50 mg/L test item.

Executive summary:

The acute fish toxicity study was conducted according to the European Community Guideline 84/449/C1 and in compliance with GLP. No mortality was observed in Gold orf (Leuciscus idus melanotus HECKEL) exposed to the arithmetic mean measured concentration of 0.50 mg/L test substance.

As the test item was of very low water solubility (<0.05 mg/L), methanol was used as the solubilizing aid. Test groups consisted of one treatment group (0.50 mg/L mean measured test substance concentration), one control group and one solvent control. All fish were kept in flow-through aquaria. The test item concentration was measured after 0, 24, 48, 72 and 96 hours. As the measured concentration were <80% of the initial concentration in two of the cases, effect concentrations were based on the arithmetic mean measured concentration. Until the end of exposure, the test item did not cause any mortality in Gold orf and therefore the 96h-LC50 was >0.50 mg/L concentration and the 96h-LC0 was >= 0.50 mg/L test item.

Validity criteria of the guideline were not fulfilled (the dissolved oxygen concentration dropped below 60% of the air saturation value in the solvent control and treatment group). However, no mortality was observed, neither in solvent control nor treatment group. Therefore, the drop in oxygen concentration does not put into question the outcome of the study. As no details on preparation of stock solution, solvent spiking of the test item (dosing / mixing scheme) and the analytical method are reported, the study is reliable with restrictions (RL2).

Description of key information

EU-method C.1 (Hüls, 1991; RL2): 96h-LC50 (Gold orf, mortality) >0.5 mg/L (arithmetic mean measured); 96h-LC0 (Gold orf, mortality) >= 0.5 mg/L (arithmetic mean measured)

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

0.5 mg/L

Additional information

The acute fish toxicity study was conducted according to the European Community Guideline 84/449/EEC C.1 and in compliance with GLP.

As the test item was of very low water solubility (<0.05 mg/L), methanol was used as the solubilizing aid. Test groups consisted of one treatment group (arithmetic mean measured: 0.5 mg/L test item), one control group and one solvent control. All fish were kept in flow-through aquaria. Effect concentrations were based on the arithmetic mean measured concentration. Until the end of exposure, the test item did not cause any mortality in Gold orf (Leuciscus idus melanotus HECKEL) and therefore the 96h-LC50 was >0.50 mg/L concentration and the 96h-LC0 was >= 0.50 mg/L test item.

Validity criteria of the guideline were not fulfilled (the dissolved oxygen concentration dropped below 60% of the air saturation value in the solvent control and treatment group). However, no mortality was observed, neither in solvent control nor in treatment group. Therefore, the drop in oxygen concentration does not put into question the outcome of the study. As no details on preparation of stock solution, solvent spiking of the test item (dosing / mixing scheme) and the analytical method are reported, the study is reliable with restrictions (RL2).