cyclohexadecanone

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:

02 - 06 Jul 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

Jul 1992

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Version / remarks:

Dec 1992

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Niedersächsisches Umweltministerium, Hannover, Germany

Analytical monitoring:

yes

Details on sampling:

- Concentrations: control, and 100 mg/L
- Sampling method: of the 6 L freshly prepared test suspension, 1 L was used for analysis
- Sample storage conditions before analysis: if necessary, samples were stored at 7 ± 2 °C until analysis

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Controls: yes, dilution water without test item
- Evidence of undissolved material: no, the test item was clearly dissolved throughout exposure after filtration with 0.45 µm filters

Test organisms (species):

other: Brachydanio rerio

Details on test organisms:

TEST ORGANISM
- Common name: Zebra fish
- Length at study initiation: average body length = 2.46 cm
- Weight at study initiation: average body weight = 0.13 g
- Maintenance of the brood fish: in tap water of local origin, previously filtered (activated charcoal) and aerated for at least 24 h to remove chlorine, at 23 ± 2 °C and diffuse light (0.1 - 10 µmol/m2s, natural photoperiod). Water was changed at least once a week.

ACCLIMATION
- Acclimation period: at least 12 d
- Acclimation conditions: same as test
- Type and amount of food during acclimation: Trouvit 40/2; Milkivit (Bürgheim, Germany), 4 % of the fish body weight per feeding day.
- Feeding frequency during acclimation: 3 times per week

FEEDING DURING TEST
no feeding

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

40 - 180 mg CaCO3/L

Test temperature:

23 ± 2 °C

pH:

6.0 - 8.0

Dissolved oxygen:

not less than 60% of air saturation value

Nominal and measured concentrations:

nominal: control, and 100 mg/L
measured: control, and 0.10 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: glass-aquaria
- Type: loosely covered by glass tops
- size, headspace, fill volume: Fill volume: 5 L per vessel
- Aeration: yes
- Renewal rate of test solution: daily
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 1 g fish per Liter test solution

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: local tap water, filtered (activated charcoal) and aerated for at least 24 h to remove chlorine
- Culture medium different from test medium: no, same
- Intervals of water quality measurement: the water is analysed once a year according to German tap water regulation

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: natural
- Light intensity: 0.1 - 10 µmol/m2s

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- pH, temperature and O2 saturation: at the beginning of the test and every 24 h from old and new media
- total hardness: at the beginning (from the test control)
- analytic verfication: every 24 h: after 0 h and 72 h (freshly prepared media), after 24 h and 96 h (old media)
- room temperature: continuously
- mortality and behaviour: after 2, 24, 48, 72 and 96 h

TEST CONCENTRATIONS
- Range finding study: yes
- Test concentrations: control, 100 mg/L (nominal), 0.22 mg/L (initially measured)
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 0.1 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

- Behavioural abnormalities: no
- Mortality of control: 0%
- Other adverse effects control: no
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: no
- Effect concentrations exceeding solubility of substance in test medium: no

Results with reference substance (positive control):

according to the guideline, no reference item is recommended for this test

Sublethal observations / clinical signs:

The test item was analytically verified by GC-FID at the limit concentration and control after 0 h and 72 h (new media) and after 24 h and 96 h (old media). The saturated solutions (new media) prepared and measured after 0 h and 72 h contained 0.1 mg/L of the test item whereas the test item could not be detected after 24 h of exposure. The test item is supposed to be metabolised during the test. Therefore, all effect concentrations are given based on the initially mean measured test concentrations.

Validity criteria fulfilled:

yes

Conclusions:

LC50 (96 h) > 0.1 mg/L (initial mean measured concentration of saturated solution, limit test at nominal concentration of 100 mg/L, OECD 203, Danio rerio)

Description of key information

LC50 (96 h) > 0.1 mg/L (initial mean measured concentration of saturated solution, limit test at nominal concentration of 100 mg/L, OECD 203, Danio rerio)

Additional information

There is one GLP certified guideline study available, which assessed the acute aquatic toxicity of the test substance to fish according to the OECD guideline 203.

In a semi-static test with daily renewal of the test media Danio rerio were exposed to a nominal limit concentration of 100 mg/L test substance for 96 h under controlled conditions. The limit concentration was previously established in a preliminary range-finding test.

The test substance was analytically verified by GC-FID at the limit concentration and in the control in new media (prepared and measured at 0 and 72 h) and in old media (at 24 and 96 h). In new media the measured concentration was 0.10 mg/L. In 24 h old media, no test item could be detected and it was proposed that the test item is metabolised during the test. Therefore, all effect values are based on the mean initial concentration measured.

The limit concentration caused no mortality or non lethal effects. Therefore, the EC50 (96 h) was > 0.1 mg/L mean initial concentration measured, which represents the maximum soluble concentration under test conditions.