1-(2,4-dichlorophenyl)ethan-1-one

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

April 2, 1984

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

not specified

GLP compliance:

no

Analytical monitoring:

yes

Details on sampling:

Test concentrations were taken for analytical monitoring 3/4 times during the study from each tank.

Vehicle:

not specified

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Eluate: 279 mg/L diluted (stock)

Test organisms (species):

Pimephales promelas

Details on test organisms:

TEST ORGANISM
- Common name: Fathead minnow
- Age at study initiation (mean and range, SD): 32 d.
- Length at study initiation (length definition, mean, range and SD): 21.6 ± 1.633 mm
- Weight at study initiation (mean and range, SD): 0.173 ± 0.0338 g

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

45.4 mg/L as CaCO3

Test temperature:

24.5 (1.09) ºC

pH:

7.51 (0.02)

Dissolved oxygen:

6.8 mg/L

Nominal and measured concentrations:

Nominal: 0 (control), 2.22, 3.70, 6.17, 6.17, 10.3, 17.1 mg/L
Measured (average of three measurements during the test): <0.15 (control), 1.80, 3.02, 5.08, 8.40, 16.45 mg/L.
Percent recovery: 98.7 ± 2.5

Details on test conditions:

TEST SYSTEM
- Test vessel: Tank
- Material, size, headspace, fill volume: 6.3 L
- No. of organisms per vessel: 22
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2
- Biomass loading rate: 0.687 g/L

TEST MEDIUM / WATER PARAMETERS
- Alkalinity: 35.5 mg/L CaCo3

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): Mortality and effects at 0.5, 1, 3, 6, 5, 12, 24, 30, 48, 72, 96 hours.

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

11.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

11.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: effect

Details on results:

- Behavioural abnormalities: Affected fish lost equilibrium prior to death. Fish in the 10.3 mg/L concentration were hypoactive, while fish in the 6.17 mg/L concentration ceased schooling.

Sublethal observations / clinical signs:

Mortalities:

Hour	Concentrations (mg/L)
	Control		2.22		3.70		6.17		10.3		17.1
0.5	0	0	0	0	0	0	0	0	0	0	0	0
1	0	0	0	0	0	0	0	0	0	0	0	0
3	0	0	0	0	0	0	0	0	0	0	0	0
6	0	0	0	0	0	0	0	0	0	0	4	3
7	0	0	0	0	0	0	0	0	0	0	9	13
12	0	0	0	0	0	0	0	0	0	0	16	17
24	0	0	0	0	0	0	0	0	0	0	20	20
30	0	0	0	0	0	0	0	0	0	0	22	21
48	0	0	0	0	0	0	0	0	0	0	22	22
72	0	0	0	0	0	0	0	0	0	0	22	22
96	0	0	0	0	0	0	0	0	0	0	22	22

Effects:

Hour	Concentrations (mg/L)
	Control		2.22		3.70		6.17		10.3		17.1
0.5	0	0	0	0	0	0	0	0	0	0	7	7
1	0	0	0	0	0	0	0	0	1	1	15	22
3	0	0	0	0	0	0	0	0	0	0	22	22
6	0	0	0	0	0	0	0	0	0	0	22	22
7	0	0	0	0	0	0	0	0	0	0	22	22
12	0	0	0	0	0	0	0	0	0	0	22	22
24	0	0	0	0	0	0	0	0	0	0	22	22
30	0	0	0	0	0	0	0	0	0	0	22	22
48	0	0	0	0	0	0	0	0	0	0	22	22
72	0	0	0	0	0	0	0	0	0	0	22	22
96	0	0	0	0	0	0	0	0	0	0	22	22

Validity criteria fulfilled:

yes

Remarks:

(No mortality was observed by the end of the test control, the substance concentration was maintained during the test)

Conclusions:

The 96-h LC50 of test substance was determined to be 11.7 mg/L in Fathead minnow.

Executive summary:

The acute toxicity of the 1-(2,4-dichlorophenyl)ethanone to the Fathead minnow was determined by exposing groups of 22 test organisms to five concentrations of the test substance. The 96-h LC50of the test substance was determined to be 11.7 mg/L. An acute toxicity test with the test substance on Fathead Minnows (Pimephales promelas) in a flow system was performed in accordance with a method similar to OECD Guideline 203. 22 fish for tank, 32 days old, were exposed for 96 hours to nominal concentrations of 0 (control), 2.22, 3.70, 6.17, 10.3 and 17.1 mg/L (2 replicates each) test item. Affected fish lost equilibrium prior to death. Fish in the 10.3 mg/L concentration were hypoactive, while fish in the 6.17 mg/L concentration ceased schooling. The 96h-LC50 (based on mortality) of 1-(2,4-dichlorophenyl)ethanone in Fathead Minnows was determined to be 11.7 mg/l.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Test method according to national standard method (ASTM 80), well documented. No data on GLP.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

yes

Remarks:

(no data on test concentration, analytical monitoring results, 5 fish used in each treatment and control chamber)

Principles of method if other than guideline:

The study was conducted according to 'Standard practice for conducting acute toxicity tests with fishes, macroinvertebrates, and amphibians' (ASTM, 1980)

GLP compliance:

not specified

Analytical monitoring:

yes

Details on sampling:

Samples of all test solutions were taken from each test chamber and analyzed according to a monitoring program that characterized the exposure pattern. Daily determinations for each test treatment were averaged and used as the experimental exposure parameters.

Vehicle:

not specified

Test organisms (species):

Pimephales promelas

Details on test organisms:

TEST ORGANISM
- Common name: Fathead minnow
- Source: Environmental research Laboratory-Duluth culture
- Age at study initiation (mean and range, SD): Juvenile: 28- to 34-day-old.
- Weight at study initiation (mean and range, SD): 0.12 g wet weight.
- Method of breeding: Juveniles were cultured on recently hatched brine shrimp nauplii (Artemia sp.) and frozen adult brine shrimp.
- Feeding during test: fish were not fed 24 h before nor during the toxicity tests.

ACCLIMATION
- Acclimation period: 2- 3 h
- Acclimation conditions (same as test or not): same as test.

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

44.6 ± 1.4 mg/L as CaCO3

Test temperature:

25.0 ± 0.5°C

pH:

7.6 ± 0.2

Dissolved oxygen:

≥ 80 % of saturation

Nominal and measured concentrations:

4 treatment concentrations and a control.
No data reported.

Details on test conditions:

TEST SYSTEM
- Test vessel: Chambers
- Material, size, headspace, fill volume: The test chambers were constructed of glass and silicon sealant and measured 10.2x20.3x10.2 cm high or 11.4x22.9x12.7 high, and contained one or 2 L of test solution.
- Aeration: yes.
- Type of flow-through (e.g. peristaltic or proportional diluter): Diluters with continuous-flow water delivery according to Benoit et al. 1982 and Anderson and Weber 1975 were used
- Renewal rate of test solution (frequency/flow rate): Flow through each chamber was 40 or 25 mL/min, affording 99% replacement in about 2h or 95% replacement in about 4h, respectively (depending on the chamber dimensions).
- No. of organisms per vessel: 5.
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: All tests were conducted with sand and gravel, and 50 µm cotton fiber filtered water directly obtained from Lake Superior. The water was delivered through polyvinyl chloride pipes to a main stainless steel head tank.
- Alkalinity: 44.0 ± 5.2 mg/L as CaCO3)
- Intervals of water quality measurement: water from control and treatment chambers were routinely measured.

OTHER TEST CONDITIONS
- Photoperiod: 16 h daily (wide spectrum fluorescent bulbs); this included a 30-rain gradual brightening and dimming period with incandescent light to simulate dawn and dusk.
- Light intensity: 22 to 38 lumens/sq ft (at the test water surface)

EFFECT PARAMETERS MEASURED (with observation intervals if applicable):
Mortalities were recorded daily.

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 0.8

Reference substance (positive control):

yes

Remarks:

1-octanol

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

11.7 mg/L

Nominal / measured:

not specified

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: (8.40 - 16.4 mg/L)

Details on results:

- Behavioural abnormalities: Before death and after an initial excitement phase, darkening of the fish and rapid but long lasting passivity occurred.
- Other biological observations: Quick recovery of exposed fishes when transferred to clean water was also noted. If death resulted it usually occurred within hours after initial exposure. These observations point to an anesthetic like effect.
- Mortality of control: there was no control mortality in tests with juveniles and less than 10% in tests with fry.

Results with reference substance (positive control):

- 1-octanol LC50: 13.5 (12.6 - 15.3) mg/L; 0.104 (0.0968 - 0.117) mM (test performed in fry (<24h fathead minnows).

Reported statistics and error estimates:

Mortalities were recorded daily and estimated median lethal concentrations (LC50 values) and 95% confidence intervals were computed by the Trimmed Spearman-Karber Method (Hamilton et al., 1977) or a log-probit method (Stephan, 1977).

Validity criteria fulfilled:

yes

Remarks:

(mortalities < 10% in controls, O2 content >60% saturation, concentration of the substance suposed to be mantained)

Conclusions:

The 96-h LC50 of test substance was determined to be 11.7 mg/L in Fathead minnonw.

Executive summary:

The acute toxicity of the test substance to the Fathead minnow (Pimephales promelas) was determined according to Standard practice for conducting acute toxicity tests with fishes, macroinvertebrates, and amphibians (ASTM, 1980). 5 juvenile fish were exposure to four concentration levels and a control (20 fish per treatment level in total) of the test item for 96 h under flow-through conditions). Test substance concentrations were measured daily. Dead fish were recorded daily. Based on the results the 96h-LC50 of test substance was determined to be 11.7 mg/L in fathead minnow.

Reference 3

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

secondary literature

Principles of method if other than guideline:

Data were obtained from fathead minnow acute mortality database established by the U.S. Environmental Protection Agency at the National Health and Environmental Effects Research Laboratory Mid-Continental Ecology Division (formerly the Environmental Research Laboratory) in Duluth, Minnesota. Fish used in these tests were approximately 30 d of age. At the start of a test, fish were distributed randomly to a density of 25 fish per chamber. Fish were not fed during the experiment. During exposure to the toxicant, the fish were routinely observed for behavioral responses (effects) and deaths. Dead fish were removed and recorded periodically up to 96 h from initial exposure. The 96-h median lethal concentration (LC50) was calculated with the trimmed Spearman–Karber technique.

GLP compliance:

not specified

Analytical monitoring:

not specified

Vehicle:

not specified

Test organisms (species):

Pimephales promelas

Details on test organisms:

TEST ORGANISM
- Common name: fathead minnow.
- Age at study initiation (mean and range, SD): approximately 30 d of age.
- Length at study initiation (length definition, mean, range and SD): unusually large or small individuals were removed.
- Feeding during test: no

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Details on test conditions:

TEST SYSTEM
- Test vessel: chamber.
- No. of organisms per vessel: 25 per chamber (randomly)

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : During exposure to the toxicant, the fish were routinely observed for behavioral responses (effects) and deaths.

Reference substance (positive control):

not specified

Key result

Duration:

96 h

Dose descriptor:

other: Log (1/LC50)

Effect conc.:

1.21 mmol/L

Nominal / measured:

not specified

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Reported statistics and error estimates:

The 96-h median lethal concentration (LC50) was calculated with the trimmed Spearman–Karber technique.

Sublethal observations / clinical signs:

Log (1/LC50) = 1.21 mmol/L

LC50 = 0.0616 mmol/L

LC50 = 11.64 mg/L

Validity criteria fulfilled:

not specified

Conclusions:

The log(1/LC50) for a 96 hour exposure to the test item was reported to be 1.21 mmol/L (LC50 ~ 11.6 mg/L) in Fathead minnow (based on mortality).

Executive summary:

The acute toxicity of the test substance to the fathead minnow was determined by a 96 -h flow-through test. Fish used in this test were approximately 30 d of age. At the start of a test, fish were distributed randomly to a density of 25 fish per chamber. Fish were not fed during the experiment. During exposure to the toxicant, the fish were routinely observed for behavioral responses (effects) and deaths. Dead fish were removed and recorded periodically up to 96 h from initial exposure. The 96-h median lethal concentration (LC50) was calculated with the trimmed Spearman–Karber technique. The log(1/LC50) for a 96 hour exposure to the test item was reported to be 1.21 mmol/L (LC50 ~ 11.6 mg/L) in Fathead minnow (based on mortality).

Description of key information

Key study: Test method similar to OECD 301. No GLP. The 96h-LC50 (based on mortality) was determined to be 11.7 mg/l in Fathead minnows.

Supporting study: Test method ASTM, 1980. No data on GLP. The 96h-LC50 (based on mortality) was determined to be 11.7 mg/l in Fathead minnows.

Supporting study: No data on test method. No data on GLP. The log(1/LC50) for a 96 hour exposure to the test item was reported to be 1.21 mmol/L (LC50~11.6 mg/L) in Fathead minnow (based on mortability).

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

11.7 mg/L

Additional information

Key study: An acute toxicity study was performed on 1-(2,4-dichlorophenyl)ethanone by Brooke et al. 1984 with a test method similar to OECD Guideline 203. 22 Fathead minnows (Pimephales promelas) per group (two replicate each) were exposed to acetone oxime at 0 (control), 2.22, 3.70, 6.17, 10.3 and 17.1 mg/L for 96 hours. The LC50 (based on mortality) was determined to be 11.7 mg/l.

Supporting study: The acute toxicity of the test substance to the Fathead minnow (Pimephales promelas) was determined according to Standard practice for conducting acute toxicity tests with fishes, macroinvertebrates, and amphibians (ASTM, 1980). 5 juvenile fish were exposure to four concentration levels and a control of the test item for 96 h under flowh-through conditions). Based on the results, the 96h-LC50 of test substance was determined to be 11.7 mg/L in fathead minnow.

Supporting study: Data were obtained from fathead minnow acute mortality database established by the U.S. Environmental Protection Agency at the National Health and Environmental Effects Research Laboratory Mid-Continental Ecology Division (formerly the Environmental Research Laboratory) in Duluth, Minnesota. In this tests, 25 fish per concentrations are exposure for 96h to the toxicants. The log(1/LC50) was reported to be 1.21 mmol/L (LC50 ~ 11.6 mg/L) in Fathead minnow (based on mortality).