Butanone

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:

1998

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

Analytical monitoring:

yes

Details on sampling:

- Sampling method: water samples were collected from mid-depth of each test chamber at test initiation and at test termination in glass scintillation vials and were analyzed immediately without storage.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION: A primary stock solution was prepared by dissolving the test substance directly in dilution water at a concentration of 50 mg MEK/mL. The primary stock was stirred with an electric mixer for approx. 30 min to aid in the solubilization. The test solutions were prepared by proportional dilution of the primary stock with dilution water. All test solutions appeared clear and colourless.

- Differential loading: 0.2 g fish/L of test water

Test organisms (species):

Pimephales promelas

Details on test organisms:

TEST ORGANISM
- Common name: fathead minnow
- Strain: not reported
- Source: Chesapeake Cultures, Hayes, Virginia
- Age at study initiation (mean and range, SD): not reported
- Length at study initiation (length definition, mean, range and SD): mean = 21 mm, range = 19 to 23 mm
- Weight at study initiation (mean and range, SD): mean = 0.14 g, range = 0.1 to 0.20 g
- Feeding during test; none

ACCLIMATION
- Acclimation period: 49 hours
- Acclimation conditions (same as test or not): same

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

None

Hardness:

136 mg/L as CaCO3

Test temperature:

22 +/- 2 degrees Celsius

pH:

8.2 to 8.6 pH

Dissolved oxygen:

exceed 60%

Salinity:

Not applicable

Nominal and measured concentrations:

Nominal - 1296, 2160, 3600, 6000, and 10000 mg MEK/L
Measured (arithmetric mean of duplicate samples at T0 and T96h)- 1170, 1848, 2993, 3758, and 6090 mg MEK/L
Measured (geometric mean of duplicate samples at T0 and T96h)- 1170, 1836, 2973, 3223, and 5370 mg MEK/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 19-L glass aquaria with a depth of 8.4 cm.
- Type: closed and not aerated i.e. little opportunity for water/air exchange
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 1
- Biomass loading rate: 0.20 g fish/L


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: primary stock solution was prepared by dissolving the test substance directly in dilution water at a concentration of 50 mg MEK/mL. The primary stock was stirred with an electric mixer for approximately 30 minutes to aid in the solubilization of the test substance. The test solutions were prepared by proportional dilution of the primary stock with dilution water. All test solutions appeared clear and colourless.
- Total organic carbon: < 1 mg C/L
The water used for culturing and testing was freshwater obtained from a well approximately 40 meters deep located on the Wildlife International Ltd. site. The well water is characterized as moderately hard water. The water is routinely monitored to ensure there will be no interferences with ecotoxicity testing.

Reference substance (positive control):

no

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

2 973 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CL 2952 and 2994 mg/L

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

1 170 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

other: lethargy at higher doses

Duration:

96 h

Dose descriptor:

EC0

Effect conc.:

1 836 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: ; no mortality concentration

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

2 973 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CL: 2952 - 2994 mg/L

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

2 973 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CL 2952 - 2994 mg/L

Duration:

72 h

Dose descriptor:

LC50

Effect conc.:

2 973 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: 95% CL 2952 - 2994 mg/L

Details on results:

-Mortality: in 1170, 1836, 2973, 3223, and 5370 groups was 0, 0, 50, 100 and 100%
- Behavioural abnormalities: one fish in the 1836 mg/L was observed to be lethargic

Results with reference substance (positive control):

Not applicable

Reported statistics and error estimates:

LD50 and 95% confidence intervals were calculated with a log-logistic model.

Validity criteria fulfilled:

yes

Description of key information

The substance was not acutely toxic to freshwater fish when tested according to OECD TG 203 (Fish, acute toxicity test). The 96-hour LC₅₀ in freshwater fish was 2973 mg/L based on measured geometric mean concentrations.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

2 973 mg/L

Additional information

Three studies addressing short-term toxicity to fish are presented in the dossier. Please refer to the document attached to Section 13 for further discussion of the studies.

Short-term toxicity to fish.001 – Fathead minnow – 1998 - key: Acute toxicity to the freshwater fish Pimephales promelas (Fathead minnow) was assessed according to OECD TG 203 (Fish, acute toxicity test) under Good Laboratory Practice (GLP). Five concentrations at nominal values of 1296, 2160, 3600, 6000, and 10000 mg/L were utilized in this test with 20 fish per concentration under static conditions. The vessels were closed and not aerated. Temperature was maintained at 22 ± 2°C and pH ranged between 8.2 and 8.6. The percentage of dead fish was recorded at 24, 48, and 96 hours, along with visible abnormalities. The following validity criteria were met: mortality in the control did not exceed 10% at the end of the test; dissolved oxygen concentrations remained above 60% of the air saturation value at the end of the test; and the pH of the control and of the test solution did not vary by more than one unit during the course of the test. The concentration of the test item was maintained close to or within 80% of the initial value throughout the test for the 3 lowest doses (1296, 2160, and 3600); however, the 2 highest doses were not maintained within 80% of the initial value throughout the test. The geometrical mean of the measured concentrations at T0 and T96h were 1170, 1836, 2973, 3223, and 5370 mg/L, which were used to express the results of the test. The mortality: in 1170, 1836, 2973, 3223, and 5370 mg/L groups were 0, 0, 50, 100 and 100% and one fish in the 1836 mg/L was observed to be lethargic. The 96 h LC₅₀ was calculated to be 2973 mg/L with 95% confidence limits of 2952 and 2994 mg/L.

Short-term toxicity to fish.003 – Golden orf - 1978: Acute toxicity to the freshwater fish Leuciscus idus melanotus (Golden orf) was assessed according to Deutsche Einheitsverfahren zur Wasser-, Abwasser- und Schlammuntersuchung. L 15: Fischtest (Bestimmung der Wirkung von Wasserinhaltsstoffen auf Fische) not according GLP (pre-dates GLP). The fish were exposed to the substance under static conditions for 48 hours. The 48–hour LC₅₀ was determined to range between 4600 and 4880 mg/L. This lower toxicity over a shorter exposure period is in keeping with the result of the key study.

Short-term toxicity to fish.002 - Goldfish - 1973: Acute toxicity to the freshwater fish Carassius auratus (Goldfish) was assessed according to OECD guideline 203 (Fish, acute toxicity test) not according GLP (pre-dates GLP). The fish were exposed to the substance under static conditions for 24 hours.  The median tolerance limit (TLm: the concentration at which 50% animals survive) at 24 hours was reported to be greater than 5000 mg/L. Detailed information was not provided in the report however, the results are in line with the key study.