3-anilino-5-methyl-5-(4-phenoxyphenyl)-1,3-oxazolidine-2,4-dione;famoxadone (ISO)

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

other: EPA OPP 123-2

Version / remarks:

1989

GLP compliance:

yes

Specific details on test material used for the study:

Purity: 97.8%
Batch: DPX-JE874-221

Analytical monitoring:

yes

Vehicle:

yes

Remarks:

control and solvent control (DMF)

Details on test solutions:

A rangefinding study was conducted along with a definitive test.

Test organisms (species):

Skeletonema costatum

Test type:

static

Water media type:

saltwater

Remarks:

Water used for acclimation of test organisms and for all toxicity testing was sterile enriched marine media adjusted to a target pH of 8.0 士 0.1 with 0.1 N hydrochloric acid.

Total exposure duration:

120 h

Test temperature:

19.7 - 20.9 °C

pH:

8.1 - 9.6

Nominal and measured concentrations:

Nominal concentrations: 0 µg/L (control and solvent control), 10, 16, 27, 45, and 75 µg/L.
Initial measured concentrations: ND (none detected at or above the limit of quantitation of 3.99 µg/L; control and solvent control), 9.09, 14.5, 20.8, 46.3, and 75.0 µg/L.

Details on test conditions:

Algae were randomly distributed among three replicates of each control and test concentration at the rate of approximately 10,000 cells/mL within 30 minutes of test substance addition. A fourth and fifth control replicate, also inoculated with algae at an identical rate, was established to provide media for the matrix spike samples prepared at 120 hours, if needed. Two stability blank samples were also prepared at a nominal concentration of 75 µg/L. One sample was shielded from the light by encasing the test vessel in foil. The stability blank samples were not inoculated with algae and were incubated under test conditions. The test was performed in 250 mL glass Erlenmeyer flasks (typically approximately 80 mm bottom diameter X 130 mm height) that contained 50 mL of test solution. The test solution depth approximately 2 cm. Test vessels were loosely capped with inverted glass beakers and randomly arranged on a rotary shaker adjusted to 100 rpm in an incubator during the test (a random numbers table was used to select the location for each vessel). The test vessels were repositioned daily.

Duration:

120 h

Dose descriptor:

EC50

Effect conc.:

> 75 µg/L

Nominal / measured:

meas. (initial)

Basis for effect:

growth rate

Duration:

120 h

Dose descriptor:

EC50

Effect conc.:

> 75 µg/L

Nominal / measured:

meas. (initial)

Basis for effect:

cell number

Details on results:

The algal population grew well and was in log phase growth, resulting in an average of 2,693,000 cells/mL in the control after 120 hours. The 120 hour EC50 value determined with either the number of cells per mL or the average specific growth rate is >75.0 µg/L Famoxadone. No effects (size differences, unusual cell shapes, colors, flocculations, adherence of cells to test containers, or aggregation of cells) were noted during the test. The 120 hour NOEC is 75.0 µg/L Famoxadone when calculated using either the number of cells/mL or the average specific growth rate.

Validity criteria fulfilled:

yes

Conclusions:

The 120 hour EC50 value determined with either the number of cells per mL or the average specific growth rate is >75.0 µg/L Famoxadone.
The 120 hour NOEC is 75.0 µg/L Famoxadone when calculated using either the number of cells/mL or the average specific growth rate.

Executive summary:

The acute toxicity of Famoxadone Technical to the marine alga, Skeletonema costatum, was conducted according to EPA OPP guideline 72-3. The test was performed under static conditions with five concentrations of test substance, a solvent control, and a dilution water control at 20 ± 2°C. Nominal concentrations of Famoxadone Technical were 0 µg/L (control and solvent control), 10, 16, 27, 45, and 75 µg/L. The highest tested nominal concentration was above the reported solubility of the test substance in freshwater of approximately 49 µg/L at 20°C. Initial measured concentrations of Famoxadone were ND (none detected at or above the limit of quantitation of 3.99 µg/L; control and solvent control), 9.09, 14.5, 20.8, 46.3, and 75.0 µg/L. Samples collected at 120 hours resulted in values that were ail less than 70% of the nominal concentrations, initial measured concentrations calculations. No insoluble material was noted during the toxicity test.

 

The 120 hour EC50 value determined with either the number of cells per mL or the average specific growth rate is >75.0 µg/L Famoxadone. No effects (size differences, unusual cell shapes, colors, flocculations, adherence of cells to test containers, or aggregation of cells) were noted during the test. The 120 hour NOEC is 75.0 µg/L Famoxadone when calculated using either the number of cells/mL or the average specific growth rate.

 

Reference 2

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

Qualifier:

according to guideline

Guideline:

other: EPA OPP 123-2

Version / remarks:

1989

GLP compliance:

yes

Specific details on test material used for the study:

Purity: 97.4%
Batch: DPX-JE874-221

Analytical monitoring:

yes

Vehicle:

yes

Remarks:

control and solvent control (DMF)

Details on test solutions:

A rangefinding study was conducted along with a definitive test.

Test organisms (species):

Scenedesmus capricornutum

Test type:

static

Water media type:

freshwater

Total exposure duration:

120 h

Test temperature:

22.5 - 23.7 °C

pH:

7.3 - 8.3

Nominal and measured concentrations:

Nominal concentrations: 6.3, 13, 25, 50, and 100 µg/L.
Initial measured concentrations: 3.9, 9.2, 16, 38, and 86 µg/L.

Details on test conditions:

The test and control vessels were placed in a light and temperature controlled environmental chamber. The cultures were incubated for 120 hours without medium renewal. Illumination was supplied by cool white fluorescent tubes. Agitation was accomplished by stirring continuously on a gyratory shaker.

Duration:

120 h

Dose descriptor:

EC50

Effect conc.:

> 86 µg/L

Nominal / measured:

meas. (initial)

Basis for effect:

growth rate

Duration:

120 h

Dose descriptor:

EC50

Effect conc.:

27 µg/L

Nominal / measured:

meas. (initial)

Basis for effect:

other: cell density

Duration:

120 h

Dose descriptor:

EC50

Effect conc.:

23 µg/L

Nominal / measured:

meas. (initial)

Basis for effect:

other: area under the curve

Details on results:

The effects upon algal growth and reproduction were found to be algistatic.

Validity criteria fulfilled:

yes

Conclusions:

120-h EC50 (Selenastrum Capricornutum) = 27 µg/L based on cell density
120-h EC50 (Selenastrum Capricornutum) = 23 µg/L based on area under the curve
120-h EC50 (Selenastrum Capricornutum) > 86 µg/L based on growth rate

120-h NOEC (Selenastrum Capricornutum) = 16 µg/L based on cell density
120-h NOEC (Selenastrum Capricornutum) = 3.9 µg/L based on area under the curve
120-h NOEC (Selenastrum Capricornutum) = 16 µg/L based on growth rate

Executive summary:

 

The acute toxicity of Famoxadone Technical to the alga, Selenastrum Capricornutum, was conducted according to EPA OPP guideline 72-3. The test was performed under static conditions with five concentrations of test substance, a solvent control, and a dilution water control at 20 ± 2°C. Nominal concentrations of Famoxadone Technical were 0 µg/L (control and solvent control), 6.3, 13, 25, 50, and 100 µg/L. Initial measured concentrations of Famoxadone were 3.9, 9.2, 16, 38, and 86 µg/L.

120-h EC50 (Selenastrum Capricornutum) = 27 µg/L based on cell density

120-h EC50 (Selenastrum Capricornutum) = 23 µg/L based on area under the curve

120-h EC50 (Selenastrum Capricornutum) > 86 µg/L based on growth rate

 

120-h NOEC (Selenastrum Capricornutum) = 16 µg/L based on cell density

120-h NOEC (Selenastrum Capricornutum) = 3.9 µg/L based on area under the curve

120-h NOEC (Selenastrum Capricornutum) = 16 µg/L based on growth rate

Reference 3

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

August 29, 1997 - November 15, 1997

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

other: EPA OPP 123-2

Version / remarks:

1989

GLP compliance:

yes

Specific details on test material used for the study:

Purity: 97.8%
Batch: DPX-JE874-221

Analytical monitoring:

yes

Details on sampling:

Analytical determination of Famoxadone was performed with 25 mL samples collected using a 25 mL graduated glass pipet from each concentration prior to its transfer to replicate test vessels at 0 hours and with 25 mL samples collected from pooled test vessel at 120 hours. Test media samples collected at 120 hours were centrifuged for approximately 20 minutes to remove algal cells. All samples were collected into 120 mL amber glass bottles containing 20 mL hexane and 5 drops of 0. IN hydrochloric acid. The bottles were gently shaken and transferred to separatory funnels. The bottles were rinsed with 5 mL of hexane which was then added to the separatory funnel. The funnels were shaken for approximately 3 minutes, allowed to settle for approximately 2 minutes, and the hexane layer was collected into 200 mL TurboVap tubes. The samples were evaporated to dryness at approximately 40 °С under a stream of nitrogen. Each sample was then reconstituted with 2 mL of a 50/50 (v/v) acetonitrile/water solution and sonicated for approximately 2 minutes. An aliquot of each sample was transferred to an amber autosampler vial for analysis. Samples that were not analyzed immediately were refrigerated until analysis.

Vehicle:

yes

Remarks:

control and solvent control (DMF)

Details on test solutions:

A rangefinding study was conducted along with 3 definitive tests.

A range-finding test was conducted with a control and solvent control (0 µg/L), and four nominal concentrations of Famoxadone Technical (0.50, 5.0, 50, and 730 µg/L). Four separate stock solutions (nominal concentrations = 5.0, 50, 500, and 7,300 mg/L) were prepared by bringing appropriate amounts of test substance to total volume of 100 mL with reagent grade dimethylformamide. DMF was used as a co-solvent because it has been shown to be of low toxicity to Navícula pelliculosa at the concentrations used, it is able to dissolve the test substance at concentrations high enough for practical use, and is miscible with water. Appropriate amounts of these stock solutions were added to dilution media to prepare the test concentrations. Insoluble material was not observed at any time during the test. At the conclusion of the test, there was at least 83% of the control growth in the solvent control and at 0.50 µg/L, 55% of the control growth at 5.0 µg/L, 5% of the control growth at 50 µg/L, and 0% of the control growth at 730 µg/L.

A definitive test was conducted with a control and solvent control (0 µg/L), and five nominal concentrations of Famoxadone Technical (1.0, 2.0, 4.0, 8.0, and 16 µg/L). Five separate stock solutions (nominal concentrations = 10, 20, 40, 80, and 160 mg/L) were prepared in DMF and appropriate amounts of these stock solutions were added to dilution media to prepare the test concentrations. Insoluble material was not observed at any time during the test. At the conclusion of the test, there was no effect (algal growth was approximately equal to control growth) at the highest tested concentration and the test was repeated. The analysis of samples collected at the
start of the test resulted in measured concentrations ranging from 99 to 105% of nominal
concentrations.

A second definitive test was conducted with control and solvent control (0 µg/L), and five nominal concentrations of Famoxadone Technical (10, 16, 27, 45, and 75 µg/L). Five separate stock solutions (nominal concentrations = 100, 160, 270, 450, and 750 mg/L) were prepared in DMF and appropriate amounts of these stock solutions were added to dilution media to prepare the test concentrations. Insoluble material was not observed at any time during the test. At
the conclusion of the test, there was at least 99% of the control growth in the solvent control, 75% of the control growth at 10 µg/L, 53% of the control growth at 16 µg/L, 16% of the control growth at 27 µg/L, 6% of the control growth at 45 µg/L, and 5% of the control growth at 75 µg/L. The analysis of samples collected at the start of the test resulted in measured concentrations ranging from 90 to 126% of nominal concentrations. Because some measured concentrations exceeded 120% of the nominal concentrations, the test was determined to be invalid and was repeated.

The final definitive test was conducted with five concentrations of test substance, a solvent control (0.10 mL/L DMF), and a dilution water control. Nominal concentrations of the test substance were 0 µg/L (control and solvent control), 10, 16, 27, 45, and 75 µg/L. Separate stock solutions were prepared for each concentration. The first stock solution was prepared at a nominal concentration of 750 mg/L by bringing 0.077 g of test substance to a total volume of 100 mL with DMF. The second stock solution, with a nominal concentration of 450 mg/L, was prepared by bringing 0.046 g of test substance to a total volume of 100 mL with DMF. The third stock solution with a nominal concentration of 270 mg/L, was prepared by bringing 0.028 g of test substance to a total volume of 100 mL with DMF. The fourth stock solution, with a nominal concentration of 160 mg/L was prepared by bringing 10.7 mL of the 750 mg/L stock solution to a total volume of 50 mL with DMF. The fifth stock solution, with a nominal concentration of 100 mg/L, was prepared by banging 6.7 mL of the 750 mg/L stock solution to a total volume of 50 mL with DMF. An appropriate volume of each respective stock solution was added to dilution media to prepare the test concentrations.

Test organisms (species):

Navicula pelliculosa

Details on test organisms:

Algae used for the test (Navicula pelliculosa, UTEX 664) were from a culture originally procured from the Culture Collection of Algae at the University of Texas at Austin and delivered to T.R. Wilbury Laboratories on August 19, 1997. The culture was transferred to sterile enriched media identical to media used for this test and maintained at test conditions for at least 14 days before the definitive test. The subsample of algae used to inoculate media at the start of the definitive test came from an 8 day old culture. Identification of the original culture was verified using an appropriate taxonomic key.

Test type:

static

Water media type:

freshwater

Remarks:

Sterile enriched freshwater media with sodium silicate added and adjusted to a target pH of 7.5 ± 0.1 with 0.1 N hydrochloric acid prior to use.

Total exposure duration:

120 h

Test temperature:

23.2 - 23.7 °C

pH:

7.5 - 8.1

Nominal and measured concentrations:

Nominal concentrations: 0 µg/L (control and solvent control), 10, 16, 27, 45, and 75 µg/L.
Initial measured concentrations: ND (none detected at or above the limit of quantitation of 3.99 µg/L; control and solvent control), 9.873 16.7, 30.7, 48.5, and 79.8 µg/L

Details on test conditions:

Algae were indiscriminately assigned to three randomly positioned replicate test vessels of each control and test concentration at the rate of approximately 3,000 cells/mL within 30 minutes of test substance addition. Two stability blank samples were also prepared at a nominal concentration of 75 µg/L. One sample was shielded from the light by encasing the test vessel in foil. The stability blank samples were not inoculated with algae and were incubated under test conditions. The test was performed in 250 mL glass Erlenmeyer flasks (typically approximately 80 mm bottom diameter x 130 mm height that contained 50 mL of test solution. The test solution depth was approximately 2 cm.

Test vessels were loosely capped with inverted glass beakers and randomly arranged on a rotary shaker adjusted to 100 rpm in an incubator during the test (a random numbers table was used to select the location for each vessel). The test vessels were repositioned daily. A 24 hour light and 0 hour dark photoperiod was automatically maintained with cool-white fluorescent lights that provided a light intensity of approximately 4,000 lux. The number of algal cells/mL in each test vessel and the occurrence of relative size differences, unusual cell shapes, colors, flocculations, adherence of cells to test containers, or aggregation of cells was determined visually by means of direct microscopic examination with a hemocytometer. Cell counts were recorded at 24, 48, 72, 96, and 120 hours (initial counts were calculated based on the dilution of the algal culture).

A determination of whether toxic effects were algistatic or algicidal was performed at the conclusion of the toxicity test for those concentrations exhibiting >50% inhibition. After 120 hours of testing, 0.5 rnL of solution from each replicate 16, 27, 45, and 75 µg/L (nominal) test vessel was brought up to 100 mL with fresh dilution media in a 100 mL graduated flask and transferred to respective test vessels. The resulting solutions were incubated under test conditions for 72 hours.

Duration:

120 h

Dose descriptor:

EC50

Effect conc.:

> 79.8 µg/L

Nominal / measured:

meas. (initial)

Basis for effect:

growth rate

Duration:

120 h

Dose descriptor:

EC50

Effect conc.:

13.5 µg/L

Nominal / measured:

meas. (initial)

Basis for effect:

cell number

Details on results:

The algal population grew well and was in log phase growth, resulting in an average of 1,201,000 cells/mL in the control after 120 hours. The 120 hour EC50 values determined with the number of cells per mL and the average specific growth rate are 13.5 µg/L (with a 95% confidence interval of < 9.97 to 18.7 µg/L) and >79.8 µg/L Famoxadone, respectively. No effects (size differences, unusual cell shapes, colors, flocculations, adherence of cells to test containers, or aggregation of cells) were noted during the test. The 120 hour NOEC is <9.87 µg/L when calculated using the number of cells/mL and 9.87 µg/L when calculated using the
average specific growth rate.

During the algistatic/algicidal test set up for 72 hours at the termination of the final definitive test, algae collected from each 16, 27, 45, and 75 µg/L (nominal) test vessel and combined into respective test vessels increased from calculated cell concentrations of 5000, 3140, 1440, and 1200 cells per mL to 346,000, 270,000, 302,000, and 200,000 cells/mL, respectively. These data indicate that the effect of Famoxadone Technical at these concentrations was algistatic rather than algicidal.

Validity criteria fulfilled:

yes

Conclusions:

The 120 hour EC50 values determined with the number of cells per mL and the average specific growth rate were 13.5 µg/L (with a 95% confidence interval of <9.97 to 18.7 µg/L) and >79.8 µg/L Famoxadone, respectively.
The 120 hour NOEC is <9.87 µg/L when calculated using the number of cells/mL and 9.87 µg/L when calculated using the average specific growth rate.

Executive summary:

The acute toxicity of Famoxadone Technical to the freshwater alga, Navícula

pelliculosa, was conducted according to EPA OPP 72-3. The test was performed under static conditions with five concentrations of test substance, a solvent control, and a dilution water control at 24 ± 2°C. Nominal concentrations of Famoxadone Technical were 0 µg/L (control and solvent control), 10, 16, 27, 45, and 75 µg/L. The highest tested nominal concentration was above the reported solubility of the test substance in freshwater of approximately 49 µg/L at 20°C. Initial measured concentrations of Famoxadone were ND (none detected at or above the limit of quantitation of 3.99 µg/L; control and solvent control), 9.873, 16.7, 30.7, 48.5, and 79.8 µg/L. Analysis of samples collected at 120 hours resulted in values that were all less than 70% of the nominal concentrations. Initial measured concentrations were used for all calculations. No insoluble material was noted during the toxicity test.

 

Exposure of Navícula pelliculosa to Famoxadone Technical resulted in 120 hour EC50 values determined with the number of cells per mL and the average specific growth rate of 13.5 µg/L (with a 95% confidence interval of <9.97 to 18.7 µg/L) and >79.8 µg/L Famoxadone, respectively. The 120 hour NOEC is <9.87 µg/L when calculated using the number of cells/mL and 9.87 µg/L when calculated using the average specific growth rate.

 

Reference 4

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

other: EPA OPP 123-2

Version / remarks:

1989

GLP compliance:

yes

Specific details on test material used for the study:

Purity: 97.8%
Batch: DPX-JE874-221

Analytical monitoring:

yes

Vehicle:

yes

Remarks:

control and solvent control (DMF)

Details on test solutions:

A rangefinding study was conducted along with a definitive test.

Test organisms (species):

Anabaena flos-aquae

Test type:

static

Water media type:

freshwater

Remarks:

Sterile enriched freshwater media adjusted to a target pH of 7.5 ± 0.1 with 0.1 N hydrochloric acid prior to use.

Total exposure duration:

120 h

Test temperature:

23.9 - 24.5 °C

pH:

7.4 - 7.7

Nominal and measured concentrations:

Nominal concentrations: 0 µg/L (control and solvent control), 10, 16, 27, 45, and 75 µg/L.
Initial measured concentrations: ND (none detected at or above the limit of quantitation of 3.99 µg/L; control and solvent control), 8.66, 15.9, 22.1, 42.6, and 84.3 µg/L.

Details on test conditions:

Algae were indiscriminately distributed among three randomly positioned replicates of each control and test concentration at the rate of approximately 3,000 cells/mL within 30 minutes of test substance addition. A fourth and fifth control replicate was established to provide media for the matrix spike samples prepared at 120 hours, if needed. Two stability blank samples were also prepared at a nominal concentration of 75 µg/L. One sample was shielded from the light by encasing the test vessel in foil. The stability blank samples were not inoculated with algae and were incubated under test conditions. The test was performed in 250 mL glass Erlenmeyer flasks (typically approximately 80 mm bottom diameter x 130 mm height) that contained 50 mL of test solution. The test solution depth was approximately 2 cm. Test vessels were loosely capped with inverted glass beakers and randomly arranged on a rotary shaker adjusted to 100 rpm in an incubator during the test (a random numbers table was used to select the location for each vessel). The test vessels were repositioned daily.

Duration:

120 h

Dose descriptor:

EC50

Effect conc.:

> 84.3 µg/L

Nominal / measured:

meas. (initial)

Basis for effect:

growth rate

Duration:

120 h

Dose descriptor:

EC50

Effect conc.:

> 84.3 µg/L

Nominal / measured:

meas. (initial)

Basis for effect:

cell number

Details on results:

The algal population grew well and in log phase growth, resulting in an average of 715,000 cells/mL in the control after 120 hours.

The 120 hour EC50 value determined with either the number of cells per mL or the average specific growth rate is >84.3 µg/L Famoxadone. No effects (size differences, unusual cell shapes, colors, flocculations, adherence of cells to test containers, or aggregation of cells) were noted during the test. The 120 hour NOEC is 42.6 µg/L Famoxadone when calculated using either the number of cells/mL or the average specific growth rate.

Validity criteria fulfilled:

yes

Conclusions:

The 120 hour EC50 value determined with either the number of cells per mL or the average specific growth rate is >84.3 µg/L Famoxadone.
The 120 hour NOEC is 42.6 µg/L Famoxadone when calculated using either the number of cells/mL or the average specific growth rate.

Executive summary:

The acute toxicity of Famoxadone Technical to the freshwater alga, Anabaena

flos-aqüae, was conducted according to EPA OPP guideline 72-3. The test was performed under static conditions with five concentrations of test substance, a solvent control, and a dilution water control at 24 ± 2°C. Nominal concentrations of Famoxadone Technical were 0 µg/L (control and solvent control), 10, 16, 27, 45, and 75 µg/L. The highest tested nominal concentration was above the reported solubility of the test substance in freshwater of approximately 49 µg/L at 20°C. Initial measured concentrations of Famoxadone were ND (none detected at or above the

limit of quantitation of 3.99 µg/L; control and solvent control, 8.66, 15.9, 22.1, 42.6, and 84.3 µg/L. Samples collected at 120 hours resulted in values that were all less than 70% of the nominal concentrations. Initial measured concentrations were used for all calculations. No insoluble material was noted during the toxicity test.

 

The 120 hour EC50 value determined with either the number of cells per mL or the average specific growth rate is >84.3 µg/L Famoxadone. No effects (size differences, unusual cell shapes, colors, flocculations, adherence of cells to test containers, or aggregation of cells) were noted during the test. The 120 hour NOEC is 42.6 µg/L Famoxadone when calculated using either the number of cells/mL or the average specific growth rate.

 

Description of key information

Freshwater

120-hr EC50 for growth rate (Navicula pelliculosa) > 79.8 μg/L; 120-hr EC50 for cell number = 13.5 μg/L, 120-hr NOEC = 9.87 µg/L, OPP 123-2, Reliability = 1

120-hr EC50 for growth rate and cell number (Anabaenaflos-aquae) > 84.3 μg/L, 120-hr NOEC = 42.6 μg/L, OPP 123-2, Reliability = 1

120-hr EC50 for growth rate (Selenastrum Capricornutum) > 86 μg/L; 120-hr EC50 for cell density = 27 μg/L, 120-hr NOEC = 16 μg/L, OPP 123-2 and EU Method C.3, Reliability = 1

Saltwater

120-hr EC50 for growth rate and cell number (Skeletonema costatum) > 75 μg/L, 120-hr NOEC = 75 μg/L, OPP 123-2, Reliability = 1

Key value for chemical safety assessment

EC50 for freshwater algae:

79.8 µg/L

EC50 for marine water algae:

75 µg/L

EC10 or NOEC for freshwater algae:

9.87 µg/L

EC10 or NOEC for marine water algae:

75 µg/L

Additional information

Famoxadone was test in three freshwater aquatic species with a resultant 120-hr EC50’s in growth rate ranging from > 79.8 μg/L to > 86 μg/L and 120-hr NOECs for specific growth rate of 9.87 – 42.6 μg/L.  When tested in a saltwater aquatic species, the 120-hr EC50 for growth rate was > 75 μg/L and the NOEC was 75 μg/L.