Propanoic acid, 2-[4-[4,6-bis([1,1'-biphenyl]-4-yl)-1,3,5-triazin-2-yl]-3-hydroxyphenoxy]-, isooctyl ester

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

31-Jan-2003 to 21-March-2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP compliant; Guideline Study (OECD 201); Deficiencies: The coefficient of analysis of the daily growth rate in the control replicates and the coefficient of analysis of the average specific growth rates in the control replicates were not reported.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Version / remarks:

1984

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

Version / remarks:

adopted on 29th December 1992

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.5400 (Algal Toxicity, Tiers I and II) (January 2012)

Version / remarks:

adopted in April 1996

Deviations:

no

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: Japanese Ministry of Agriculture, Forestry and Fisheries, Test Data for Registration of Agricultural Chemicals, 12 Nohsan No 8747, 24 November 2000

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

444-090-3

EC Name:

-

Cas Number:

204848-45-3

Molecular formula:

C44 H43 N3 O4

IUPAC Name:

Propanoic acid, 2-[4-[4,6-bis([1,1'-biphenyl]-4-yl)-1,3,5-triazin-2-yl]-3-hydroxyphenoxy]-, isooctyl ester

Details on test material:

- Appearance: yellow powder

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

- Test concentration was verified by chemical analysis. Duplicate 200 mL samples were taken from control and the test stock solution at 0 hours and from culture vessels at 96 hours (additional replicates containing "no algae" media) for analysis. The samples were not filtered to remove algal cells before analysis.
Additional 140 mL samples were taken from flasks containing "no algae" media at 96 hours (replicate pooled).
- Sampling method:
Samples (200 mL) were extracted by liquid-liquid partitioning into dichloromethane (4x25 mL). The combined organic extracts were evaporated to dryness and the residues dissolved in sufficient THF/water (50/50 v/v) to bring the expected analyte concentration within the calibration range

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method:
80 mg of the test substance was dispersed directly into 2 L of nutrient medium to give an initial stock dispersion of 40 mg/L, which was then stirred for approximately 70 hours. The stock dispersion was then filtered through a pre-conditioned 0.45 µm cellulose nitrate membrane filter conditioned to the test substance to give a 100% saturated solution. Algal pre-culture was mixed with the control and exposure solution at a rate of 5.9 mL per 1000 mL to give a starting cell density of approximately 10E-04 cells/mL.
- Controls:
Additional flasks containing the test substance at a nominal concentration equivalent to 100% saturated solution, but without the presence of algal cells, were also prepared in order to obtain information on the extent to which the test substance was lost by either adsorption onto or absorption by the algal cells ( "no algae" test cultures).

Test organisms

Test organisms (species):

Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)

Details on test organisms:

TEST ORGANISM
- Common name: Selenastrum capricornum
- Strain: No CCAP 278/4
- Source (laboratory, culture collection):
Culture Collection of Algae and Protozoa, CEH, Windermere, Cumbria, UK
- Method of cultivation:
Flasks containing sterile nutrient medium were inoculated from a master culture and were maintained under continuous illumination (7720-8000 lux) in an orbital incubator at 24 °C to give an algal suspension in log phase growth, characterised by a cell density of 1.7 x 10E+06 cells/mL.

ACCLIMATION
- Culturing media and conditions (same as test or not): Same as test

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Remarks on exposure duration:

to fulfill requirements of OPPTS guideline

Test conditions

Test temperature:

24.7-24.8 °C

pH:

9.1-9.5

Nominal and measured concentrations:

The definitive test concentration was selected following a range finding study with concentrations of 1.0, 10 and 100% as saturated solutions. The dose response seen during this range finding test indicated that there was no significant effect at the maximum concentration of 100% saturation. In the definitive study, a single aqueous mixture was prepared at the assumed aqueous saturation level.
Nominal concentration: 100% saturated solution; 40 mg/L
Geometric mean measured concenfration: 0.42 µg/L
Nominal exposure concentrations quoted in this report refer to the test material as received; no allowance has been made for a purity of less than 100%

Details on test conditions:

TEST SYSTEM
- Test vessel: conical flasks
- fill volume: 100 mL
- Aeration: Gaseous exchange and suspension of the algal cells were ensured by the continuous oscillation of the orbital shaker platform, at 130 revolutions per minute.
- Renewal rate of test solution: none
- Initial cells density: 10000
- Control end cells density: 3648000
- No. of vessels per concentration (replicates): 6
- No. of vessels per control (replicates): 6

GROWTH MEDIUM
- Standard medium used: yes

OTHER TEST CONDITIONS
- Adjustment of pH: yes
- Photoperiod: 96 hours
- Light intensity and quality: 3960-4260 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- Determination of cell concentrations:
Measurements were taken at 24, 48, 72 and 96 hours by direct counting using a Coulter® Multisizer II particle counter. The initial counts at 0 hours were assumed based on Haemacytometer counts of the master culture and the calculations of volumes to be added.

TEST CONCENTRATIONS
- Range finding study:
The following definitive test concenfration was selected following a range finding study with concentrations of 1.0, 10 and 100% as saturated solutions. The dose response seen during this range finding indicated that there was no significant effect at the maximum concentration of 100%) saturation. In the definitive study, a single aqueous mixture was prepared at the assumed aqueous saturation level.
- Test concentrations:
Nominal concentration: 100% saturated solution
Geometric mean measured concentration: 0.42 µg/L

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

96 h

Dose descriptor:

other: ErC50

Effect conc.:

> 0.42 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: > 100% saturation; no acute toxic effects within the range of solubility.

Effect concentrations 2

Duration:

96 h

Dose descriptor:

other: EbC50

Effect conc.:

> 0.42 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: > 100% saturation; no acute toxic effects within the range of solubility.

Effect concentrations 3

Duration:

72 h

Dose descriptor:

other: EbC50

Effect conc.:

> 0.42 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

biomass

Remarks on result:

other: > 100% saturation; no acute toxic effects within the range of solubility.

Effect concentrations 4

Duration:

72 h

Dose descriptor:

other: ErC50

Effect conc.:

> 0.42 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: > 100% saturation; no acute toxic effects within the range of solubility.

Effect concentrations 5

Duration:

96

Dose descriptor:

NOEC

Effect conc.:

>= 0.42 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

cell number

Remarks on result:

other: > 100% saturation; no acute toxic effects within the range of solubility.

Details on results:

- Exponential growth in the control (for algal test): Cell concentrations in control cultures increased by a factor of at least 16 within 96 hpurs (mean cell density of controls at 0 and 96 hours: 1.0 x 10E+04 and 3.6 x E+06 cells/mL)
- Any stimulation of growth found in any treatment:
The pH of the control cultures was 8.2 at 0 hours and ranged from 9.2-9.4 at 96 hours and therefore did not remain constant to within 1 unit over the 96 hr-test period. This was concluded to be a consequence of high growth rate.

Results with reference substance (positive control):

- Results with reference substance valid?
The test was considered valid because cell concentrations in control cultures increased by a factor of at least 16 within 72 hours (mean cell density of control at 0 hours: 1.2 x 10E+04cells/mL; mean cell density of control at 72 hours: 2.6 x 10E+06 cells/mL).
- EbC50 (Area-under curve 72 hours): 0.6 mg/L
- ErC50 (Growth rate 0-72 hours): 1.1 mg/L
- NOEC: 0.1 mg/L

Any other information on results incl. tables

The test item did not inhibite the growth of the green algae after 72 and 96 hours of exposure. The presence of the algal cells did not affect the stability of the test item in test media. The median effective concentration for inhibition of growth based on biomass and average specific growth rates could not be calculated because these values lay above that achieved in the saturated aqueous mixture of the test item under the conditions of this test.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

No acute toxic effects occurred within the range of solubility. Therefore, the test substance is with high probability acutely not harmful to aquatic algae.