2-chlorophenol

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

other: US EPA 660/3-75-009 (Methods for Acute Toxicity Tests wtih Fish, Macroinvertebrates and Amphibians. Ecological Research Series)

Version / remarks:

1975

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

yes

Remarks:

acetone

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: For each test concentration, the appropriate amount of the test compound, dissolved in an appropriate solvent was pipetted into 1000 mL of dilution water and shaken vigorously for 1 min. This solution was then divided into three 200 mL aliquots in triplicate beakers to provide appropriate replication. The remaining 400 mL were used for the measurement of water quality parameters at 0 h. The exact procedure was as follows: Two stock solutions using the solvent acetone were prepared. Stock solution #1 (0.1 g test item/mL) was prepared by dissolving 1.0 g test substance in 10 mL acetone. Stock solution #2 (1 mg test item/mL) was prepared by diluting 0.1 mL of stock #1 in 10 mL acetone. For the preparation of the final test concentrations, appropriate amounts of the stock solutions were diluted in 1 L dilution water.
- Differential loading: no
- Controls: Yes. A control consisting of the same dilution water and conditions but without test substance or solvent was established. A solvent control containing a solvent concentration equal to the highest level of solvent in the test beakers was also used. The maximum solvent concentration was 1 mL/L in the highest test concentration and the solvent control.
- Chemical name of organic solvent: acetone
- Concentration of vehicle in test medium: 0.1 - 1 mL/L

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Source: in-house culture of the MIC aquatic laboratory
- Culture conditions: adult Daphnia were fed a mixture of Purina trout chow daily.
- Age of test organisms: < 24 h old

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

264 - 320 mg/L CaCO3

Test temperature:

22.1 °C

pH:

7.5 - 8.7

Dissolved oxygen:

6.7 - 8.4 mg/L

Nominal and measured concentrations:

Nominal: control, 0.1, 1, 10 and 100 mg test item/L

Details on test conditions:

TEST SYSTEM
- Test vessel: beakers
- size, headspace, fill volume: beaker volume: 250 mL; Test solution: 200 mL; Headspace = 50 mL
- Aeration: no
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3
- No. of vessels per vehicle control (replicates): 3

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: well water from St. Peters, Missouri, USA
- Chloride: 54.5 mg/L Cl-
- Alkalinity: 303 mg/L CaCO3
- Ca: 67.0 mg/L
- Mg: 2.79 mg/L
- Culture medium different from test medium: no
- Intervals of water quality measurement: dissolved oxygen, pH, alkalinity and hardness were measured at initiation and termination of the test

OTHER TEST CONDITIONS
- Adjustment of pH: no

EFFECT PARAMETERS MEASURED:
- Immobilization: at 24 and 48 h

VEHICLE CONTROL PERFORMED: yes, in triplicate (1 mL acetone/L dilution water)

RANGE-FINDING STUDY
- Test concentrations: control, 0.1, 1, 10 and 100 mg/L
- Results used to determine the conditions for the definitive study: yes, immobilization after 24 and 48 h occured at 10 mg/L and 100 mg/L

Reference substance (positive control):

no

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

5.7 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CL: 4.8 - 6.9

Details on results:

- Behavioural abnormalities: no
- Other biological observations: no

Reported statistics and error estimates:

The EC50 values were calculated using a LC50 computer program developed by Stephen et al. (1978).

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

other: Committee on Methods for Toxicity Tests with Aquatic Animals

Version / remarks:

1975

GLP compliance:

no

Analytical monitoring:

yes

Remarks:

Gas chromatography

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- dilution water: taken from Lake Superior, filtered through pre-washed 0.45 µm cellulose acetate filters and then reaerated

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Source: U.S. EPA Environmental Research Laboratory, Duluth, USA
- Culture conditions: culture water was taken directly from Lake Superior, according to procedures of Biesinger and Christensen (1972) and Biesinger et al. (1976). Water analysis from Lake Superior is presented by Biesinger and Christensen (1972). Temperatures of cultures and test beakers were maintained at 18 ± 1 °C, according to EPA recommendations.
- Age of test individuals: newly hatched females, 12 ± 12 h old

Biesinger K.E. and Christensen, G.M. (1972) Effects of various metals on survival, growth, reproduction and metabolism of Daphnia magna. J. Fish. Res. Bd Can. 29, 1691-1700.
Biesinger K.E., Lemke, A.E., Smith W.E. and Tyo, R.M. (1976) Comparative toxicity of polyelectrolytes to selected aquatic animals. J. Wat. Pollut. Control Fed. 48, 183-187.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test temperature:

18 ± 1 °C

Details on test conditions:

TEST SYSTEM
- Test vessel: beakers
- Type: covered
- size, headspace, fill volume: Beaker volume: 250 mL; Test volume: 200 mL; Headspace: 50 mL
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Lake Superior, water analysis provided by Biesinger and Christensen (1972).
- Culture medium different from test medium: no

OTHER TEST CONDITIONS
- Adjustment of pH: yes, when the addition of the test substance caused an alteration of pH of the test solutions, it was adjusted to the level of the control dilution water with the addition of sodium carbonate

EFFECT PARAMETERS MEASURED:
- mobility: after 48 h

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

3.91 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: no
- Other biological observations: no

Reported statistics and error estimates:

EC50 values were computed using log concentrations of toxicants vs moving averages of the arcsin transformation of percentage of daphnia responding (Harris, 1959, Stephan, 1977).

Reference 3

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

no guideline followed

Principles of method if other than guideline:

In order to determine the changes in the toxicity of phenol derivatives, 11 identical experiments were set up. Acute 48-h toxicity tests of copper and the phenolic compounds were examined under static non-renewal conditions, using D. magna, in a temperature-controlled room, at 25 °C, maintained with a 16-h light and 8-h dark photocycle. The mortality was defined as the number of dead organisms remaining after 48 h of exposure. The target toxic units (TUs) of the 11 binary mixtures were prepared by equitoxic combination, where the amount of each chemical exposed to D. magna was calculated based on the concentration showing an equal individual 48 h LC50 value.

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

not specified

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: the test substance was purchased from Aldrich (Milwaukee, USA)
- Controls: yes

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Source: Korean Institute of Toxicology, Daejon, South Korea
- Culture conditions: according to procedures outlined in the EPA manual (U.S. Environmental Protection Agency, 1993)
- Culture water: reconstituted hard water, with a hardness of 150 ± 10 mg/L as CaCO3, alkalinity of 121 ± 10 mg/L as CaCO3 and a pH of 8.0 ± 0.2
- Feeding: the green alga Selenastrum capricornutum and yeast, trout chow and Cerophyll (YTC) mixture (Aquatic Biosystem Inc., Fort Collins, USA)
- Age of test individual: < 24 h old

ACCLIMATION
- Type and amount of food: at a minimum of 2 h prior to the test, Daphnia were fed on YTC mixture and the green alga, S. capricornutum

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

150 ± 10 mg/L CaCO3 (reconstituted water)

Test temperature:

25 ± 1 °C

pH:

8.0 ± 0.2

Details on test conditions:

TEST SYSTEM
- Test volume: 25 mL
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4

OTHER TEST CONDITIONS
- Photoperiod: 16 h light/8 h dark

EFFECT PARAMETERS MEASURED:
- mortality: after 48 h

Reference substance (positive control):

yes

Remarks:

CuSO4 x 5*H2O

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

5.71 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

- Behavioural abnormalities: no
- Other biological observations: no

Results with reference substance (positive control):

- Relevant effect levels: LC50 (48 h) = 0.018 mg/L

Reported statistics and error estimates:

Median LC50 values were calculated using the probit analysis method (Finney, 1971).

Reference 4

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

documentation insufficient for assessment

Qualifier:

no guideline available

Version / remarks:

Secondary source from US EPS Review Programme; Guideline not specified

Principles of method if other than guideline:

Secondary source from US EPS Review Programme; Guideline not specified. Documentation insufficient for assessment.

GLP compliance:

no

Analytical monitoring:

no

Test organisms (species):

Daphnia magna

Test type:

static

Water media type:

freshwater

Total exposure duration:

48 h

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

7.43 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Reference 5

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

other: U.S. EPA "Methods for acute toxicity tests with fish, macroinvertebrates, and amphibians"

Version / remarks:

1975

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

not specified

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Either a) If sufficiently soluble in water: A stock solution was prepared in distilled water and used to provide the desired concentrations for testing. Or b) If insoluble at the desired water stock solution concentration: A stock solution in a co-solvent (triethylene, glycol, ethanol, acetone or dimethylforamide, respectively, in order of preference) was prepared. Or c) If the chemical was not sufficiently soluble in either distilled water or a co-solvent for the preparation of a stock solution: then the chemical was added directly to diluent water.
- Differential loading: possibly
- Controls: Yes. A negative control consisting of the same dilution water, test conditions and test organisms, but without test substance or co-solvent. A positive (solvent) control consisting of the same dilution water, conditions, test organisms and the highest concentration of the co-solvent present in any test vessel.
- Chemical name of vehicle (if used): triethylene, glycol, ethanol, acetone or dimethylforamide

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Source: laboratory stocks culture at EG&G, Bionomics
- Age of test organism: ≤ 24 h

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

72 ± 6 mg/L CaCO3 and/or 173 ± 13 mg/L CaCO3 (reconstituted water)

Test temperature:

22 ± 1 °C

pH:

in water with a mean hardness of 72 mg/L CaCO3: 6.7 - 8.1
in water with a mean hardness of 173 mg/L CaCO3: 7.4 - 9.4

Dissolved oxygen:

range for all tests: 6.5 - 9.1 mg/L
range within any one test: 6.6 - 8.1 mg/L

Nominal and measured concentrations:

Nominal: control and 5 - 8 test concentrations (not specified)

Details on test conditions:

TEST SYSTEM
- Test vessel: jar
- size, headspace, fill volume: Test vessel volume: 2 L; Fill volume: 150 - 500 mL; Headspace: 1500 mL - 1850 mL
- No. of organisms per vessel: Either a) 5 in 150 mL test substance, if the test substance was soluble. Or b) 15 in 500 mL test substance, if the test substance was not soluble in the diluent water or if dividing solutions presented a risk of the loss of the test substance through volatilization or if vapors of the substance posed a health risk to the investigators.
- No. of vessels per concentration (replicates): 1 - 3

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: well water
- Intervals of water quality measurement: dissolved oxygen concentration, pH and temperature of the test solutions were measured at test initiation and termination. These parameters were only measured at the end of an exposure if a potential loss of the test substance existed due to volatilization or unsolubilized test material adhering to instrument probes.

OTHER TEST CONDITIONS
- Adjustment of pH: yes

EFFECT PARAMETERS MEASURED:
mortality: at 24 and 48 h

VEHICLE CONTROL PERFORMED: yes, a positive (solvent) control was also established consisting of the same dilution water, conditions, and a number of test organisms as in the negative control and containing the highest concentration of the co-solvent present in any test vessel.

Reference substance (positive control):

not specified

Remarks:

triethylene, glycol, ethanol, acetone or dimethylforamide (if used)

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

2.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

- Behavioural abnormalities: no
- Other biological observations: no

Reported statistics and error estimates:

Mortality data were used to calculate a median LC50 (24 h/48 h) and its 95% confidence limits, either using a) the moving average angle method, b) a probit analysis, or c) a binomial probability analysis. Calculations were performed with a Hewlett-Packard Model 9815A calculator programmed to scan the data base and to select the most appropriate of the three methods.
MOVING ANGLE METHOD
The moving average angle method was used where possible. With this method, the nominal test concentrations were transformed to logarithms and the corresponding percentage mortalities to angles. Each group of three successive angles was then averaged and the LC50 was estimated by linear interpolation between the successive concentrations whose average angles bracketed 45 degrees. When the test data did not meet the method requirements, the LC50s were estimated by probit analysis.

PROBIT ANALYSIS
In the probit analysis the concentrations are converted to logarithms and percentage mortalities to probits and then a least squares linear regression analysis is calculated. If the data did not permit a probit analysis, then a binomial probability analysis was performed.

The test substances were tested based on their active ingredient and concentrations are reported as mg/L diluent water.

Reference 6

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

other: EPA-660/3-75-009 (Method for Acute Toxicity Tests with Fish, Macroinvertebrates, and Amphibians)

Version / remarks:

1975

GLP compliance:

no

Analytical monitoring:

yes

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: Dilution water from a local springfed pond was used for toxicity tests.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Source: EPA laboratory in Duluth, Minn., USA
- Age of parental stock: 2 years
- Culture conditions: according to Beisinger (1975)
- Age of test individuals: first instar Daphnia, 12 ± 12 h old

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

154.5 mg/L CaCO3 (dilution water)

Test temperature:

22 °C

pH:

7.0 - 8.2, Mean = 7.7

Conductivity:

225 - 325 µohms/cm, Mean = 290.4 µmohs/cm

Details on test conditions:

TEST SYSTEM
- No. of vessels per concentration (replicates): 2

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: local springfed pond
- Alkalinity: 95 - 156 mg/L CaCO3
- Ca: 15.4 - 62 mg/L, mean = 32.7 mg/L
- Mg: 12.4 - 41 mg/L, mean = 19.7 mg/L
- Conductivity: 225 - 325 µohms/cm
- Culture medium different from test medium: no

EFFECT PARAMETERS MEASURED:
- immobilization: after 48 h

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

6.2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 955CL: 5.56 - 6.92

Details on results:

- Behavioural abnormalities: no
- Other biological observations: no

Reported statistics and error estimates:

EC50 (48 h) values were and their 95% confidence interval were calculated by the method of Litchfield and Wilcoxon (1949).

Description of key information

EC50 (48 h): 2.6 mg/L (D. magna, U.S. EPA 1975, "Methods for acute toxicity tests with fish, macroinvertebrates, and amphibians")

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

2.6 mg/L

Additional information

There are several scientific publications available, which investigated the short-term toxicity of the test substance to aquatic invertebrates. None of the studies was performed under GLP conditions. Nevertheless, they are considered reliable for an assessment in a combined weight of evidence approach since most of the studies are performed according to internationally accepted guidelines. The reported EC50 (48 h) values for Daphnia magna are in the same order of magnitude and range from 2.6 – 7.43 mg/L.