Butanone oxime

Long-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

fish, juvenile growth test

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted according to generally vaiid procedures and according to GLP guidelines. All parameters described are closely related or comparable to guideline methods.

Qualifier:

according to guideline

Guideline:

OECD Guideline 204 (Fish, Prolonged Toxicity Test: 14-day Study)

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

- Concentrations: all
- Sampling method: sampled from middle layer of each test vessel
- Sample storage conditions before analysis: none

Details on test solutions:

Nominal concentrations of 100, 50.0, 25.0, 12.5 or 6.25mg/L and laboratory water control were tested. Solubilizer was not used. Concentrations of the test substance were kept close to the nominal concentrations throughout the 14-day test (99 to 106 %).

Test organisms (species):

Oryzias latipes

Details on test organisms:

10 fish per exposure or control group
TEST ORGANISM
- Common name:Medaka
- Strain:Oryzias latipes
- Source: Nakashima Fish Farm
- Age at study initiation (mean and range, SD):
- Length at study initiation :1.9 cm (1.8 to 2.0 cm),
- Weight at study initiation:0.095 g (0.082 to 0.11 g)
- Feeding during test Yes
- Food type:TetraMin (TetraWerke)
- Amount:2% of the fish weight
- Frequency: daily

ACCLIMATION
- Acclimation period: more than 12 days
- Acclimation conditions: same as test

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

14 d

Test temperature:

23.8 to 24.2°C.

pH:

7.0 to 7.5

Dissolved oxygen:

7.6 to 8.0 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 1.8 L/test vessel
- Type (delete if not applicable): open / closed
- Aeration: no
- Type of flow-through (e.g. peristaltic or proportional diluter):
- Renewal rate of test solution (frequency/flow rate): 25 ml/min
- No. of organisms per vessel:1
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates):
- No. of vessels per vehicle control (replicates):
- Biomass loading rate:

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water:
- Total organic carbon:
- Particulate matter:
- Metals:
- Pesticides:
- Chlorine:
- Alkalinity:
- Ca/mg ratio:
- Conductivity:
- Culture medium different from test medium:
- Intervals of water quality measurement:

OTHER TEST CONDITIONS
- Adjustment of pH:
- Photoperiod:
- Light intensity:

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :

TEST CONCENTRATIONS
- Spacing factor for test concentrations:
- Justification for using less concentrations than requested by guideline:
- Range finding study
- Test concentrations:
- Results used to determine the conditions for the definitive study:

Duration:

14 d

Dose descriptor:

NOEC

Effect conc.:

ca. 50 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

length

Remarks:

in young fish

Duration:

14 d

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks:

in young fish

Details on results:

- Type of and number with morphological abnormalities: none
- Type of and number with behavioural abnormalities: none
- Other biological observations: light body color in one fish at 100 mg/l
- Incidents in the course of the test which might have influenced the results: none

Validity criteria fulfilled:

yes

Conclusions:

For the freshwater fish Oryzias latipes, the 14-day LC50 (mortality in young fish) and NOEC (length in young fish) are calculated to be >100 mg MEKO/L and 50 mg MEKO/L, respectively.

Description of key information

The 14-d NOEC of 50 mg/L in Oryzias latipes will be used in the assessment.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

50 mg/L

Additional information

One long-term toxicity study with freshwater fish, Oryzias latipes, is available for MEKO. The test is a flow-through GLP-compliant, OECD Guideline 204 study with analytical monitoring (Kurume Laboratory, 1998b). The 14-d NOEC is >100 mg/L based on mortality and ca. 50 mg/L based on length in young fish.