Hexan-6-olide

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:

3rd to 7th February 1992

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch: Solvay Duphar, 's-Graveland
- Lot/batch: batch WA 2809/0791
- Purity test date: >99%

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: aluminum container.

Analytical monitoring:

yes

Details on sampling:

At test initiation and at 48 hours and 96 hours after initiation, and when all fish in an aquarium had died, five samples of each test solution (5 x 0.5ml) were taken and combined to one final sample. This was done in duplicate. Control solutions were not sampled after 48 hours. To each sample 625µl acetonitrile was pipetted to bring the sample to mobile phase composition. The samples were analysed directly with HPLC.

Vehicle:

yes

Details on test solutions:

6.0g e-Caprolactone was dissolved in 6l ISO-water. The solution was stirred during addition of the test substance and for 10 minutes after. Samples of 1500, 750, 375, 187 and 93ml were made up to 3l with ISO-water. The remaining portion of 3l stock solution was used for the highest concentration. Final nominal concentrations were: 1000, 500, 250, 125, 62, 31 and 0mg/l. The ISO-water was prepared and aerated at least 24 hours prior to use.

Test organisms (species):

Poecilia reticulata

Details on test organisms:

Guppies (Poecilia reticulata), obtained from a commercial supplier (RASBORA, The Netherlands). The guppies arrived 3 weeks prior to the start of the main study. They were held in a plastic container of 40x60x40cm containing approximately 80L reconstituted ISO-water, which was continuously filtered and aerated. The aquaria were kept in a room with a temperature of 21±1° C. Fish were fed troutfeed and waterfleas daily.
The guppies used in the test were 2.1-3.2 cm long, and the mean weight was 0.28g per fish.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

none

Hardness:

~250 mg/l

Test temperature:

21.3 - 22.5° C

pH:

7.5-7.8

Dissolved oxygen:

7.3 - 8.4 mg/l

Nominal and measured concentrations:

Nominal concentrations: 0 (control), 31, 62, 125, 250, 500, 1000 mg/l (see below for a table listing the measured concentrations).

Details on test conditions:

One test aquarium was used per concentration, each aquarium contained 10 fish. The test aquaria were placed in a climate chamber where the temperature was maintained at 22±1 C. The fish were not fed during the test. The test solutions were aerated during the test. The light regime was 16h light and 8h dark.

Reference substance (positive control):

yes

Remarks:

potassium bichromate

Key result

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

250 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.:

280 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

900 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

480 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

72 h

Dose descriptor:

LC50

Effect conc.:

280 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

None of the fish in the control solution died in 96 hours. Mortality was only seen at concentrations of 250 mg/l (10% mortality at 96 hours), 500 mg/l (100 % mortality at 72 hours) and 1000 mg/l (100% mortality at 24 hours). Fish that died at the higher concentrations showed uncontrolled movement and hypoactivity before death.95% confidence limits could not be determine due to the wide gap between the percentage in morntality. Indeed, at 96h 10 % mortality was found at 250 mg/l and 100% at the next concentration tested of 500 mg/l
4h after exposure to 1000 mg/l e-Caprolactone, 2 fish showed uncontrolled movement, 7 were less active and 1 was dead.
24h after exposure to 500 mg/l e-Caprolactone, 2 fish out of 10 showed uncontrolled movement.
48h after exposure to 500 mg/l e-Caprolactone, 3 fish showed uncontrollable movement, and 7 were dead.
No effects were observed at the lower concentrations.

Results with reference substance (positive control):

An acute toxicity study is conducted yearly at the laboratory with P. reticulata, using potassium bichromate as the reference substance. The most recently conducted test was conducted during November 1990. The 96h EC50 was 135 mg/l with a 95% confidence interval of 115-150 mg/l.

Reported statistics and error estimates:

The probit analysis model was used to determine the LC50 value from the percentage mortality and nominal test concentration. Because no data between 0 or 10 and 100% mortality were available, no confidence limits could be defined.

Validity criteria fulfilled:

yes

Conclusions:

The acute toxicity of the test material to guppies (Poecilia reticulata) was tested according to OECD 203 guideline at nominal test concentrations of 1000, 500, 250, 125, 62, 31 and 0 mg/l in ISO-water. The 96 hour LC50 was 280 mg/l. The NOEC for mortality and other effects was 250 mg/l. The lower concentration causing 100% mortality was 500mg/l. The 96 hour LD50 was 280mg/l.

Executive summary:

The acute toxicity of the test material to guppies, Poecilia reticulata, was tested according to OECD 203 guidelines. The study was reliable (Klimish 1) and conducted following the GLP standards. Fish were exposed at nominal test concentrations of 0-1000 mg/l in ISO-water. Nominal and measured concentrations of the test material were in accordance throughout the 96h test period. The 96 hour LC50 was 280 mg/l. The NOEC for mortality and other effects was 250 mg/l.

Description of key information

The acute toxicity of the test material to guppies (Poecilia reticulata) was tested according to OECD guideline 203 at nominal test concentrations range 0 -1000 mg/l in ISO-water. The 96 hour LC50 was 280 mg/l. The NOEC for mortality and other effects was 250 mg/l.  The lower concentration causing 100% mortality was 500mg/l. The 96 hour LD50 was 280mg/l.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

280 mg/L

Additional information

The acute toxicity of the test material to guppies,Poecilia reticulata,was tested according to OECD guideline 203. The study was reliable (Klimish 1) and conducted following the GLP standards. Fish were exposed at nominal test concentrations of 0-1000 mg/l in ISO-water. Nominal and measured concentrations of the test material were in accordance throughout the 96h test period. The 96 hour LC50 was 280 mg/l. The NOEC for mortality and other effects was 250 mg/l.