EPOFLOC L-1R

Toxicity to aquatic algae and cyanobacteria

Link to relevant study record(s)

Reference

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

4th - 7th February 2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

yes

Remarks:

- The coefficient of variation was 36.52% when it should be <35%. Removal of an outlier brings it down to 34.22% and this is therefore not considered significant.

GLP compliance:

yes (incl. QA statement)

Vehicle:

no

Test organisms (species):

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

Details on test organisms:

TEST ORGANISM
- Common name: Pseudokirchneriella subcapitata
- Strain: CCAP 278/4
- Source (laboratory, culture collection): Culture Collection, The Scottish Association for Marine Sciences (SAMS)

ACCLIMATION
- Culturing media and conditions (same as test or not): Temperature: 21 - 24°C, controlled at ±2°C; Illumination: 6000 - 8000 lux continuous white light; Shaking: Orbital set to 200 rpm

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Hardness:

No data

Test temperature:

21.3 - 21.7°C

pH:

7.08 - 8.06

Dissolved oxygen:

No data

Salinity:

No data

Nominal and measured concentrations:

0 (Control), 0.1, 0.32, 1, 3.2, 10 and 32 mg/l

Details on test conditions:

TEST SYSTEM
- Test vessel: 250 ml conical flask
- Material, size, headspace, fill volume: Test volume: 100 ml
- Initial cells density: 1 x 104 cells/ml
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 6

GROWTH MEDIUM
- Standard medium used: yes (according to OECD guidelines) - see Appendix 1 of the attached report for composition of the culture medium.

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Tests performed in deionised water with added nutrients.
- Intervals of water quality measurement: pH and temperature were measured. Water qualities determinantions on pooled replicates for each test and control solution were carried out immediately after to initiating the test and at the end of the 72 hour test period.

OTHER TEST CONDITIONS
- Sterile test conditions: Before use the water was sterilised by autoclaving at 120°C for 15 minutes. Sterile nutrient stock solutions were then added and the pH value adjusted to 8.1 ± 0.1 to obtain the culture medium.
- Light intensity and quality: 6000 - 8000 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): 48 and 72 hour EyC10, EyC20 and EyC50, 48 and 72 hour ErC10, ErC20 and ErC50; 48 and 72 hour NOEC
- Determination of cell concentrations: Haemocytometer and microscope

TEST CONCENTRATIONS
- Range finding study: Yes - A preliminary study was conducted - duration 72 hours. A single replicate at each concentration.
- Test concentrations: 0, 0.1, 1, 10 and 100 mg/l
- Results used to determine the conditions for the definitive study: 72h EC50 between 1 and 10 mg/l (by growth rate) and between 0.1 and 1 mg/l (by yield).

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

0.32 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Key result

Duration:

72 h

Dose descriptor:

other: ErC50

Effect conc.:

9.05 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% confidence limits: 4.52 – 19.3 mg/l

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

0.32 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: Yield

Duration:

72 h

Dose descriptor:

other: ErC20

Effect conc.:

3.03 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% confidence limits: 0.38 – 5.63 mg/l

Duration:

72 h

Dose descriptor:

other: ErC10

Effect conc.:

1.71 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% confidence limits: 0.08 – 3.71 mg/l

Duration:

72 h

Dose descriptor:

other: EyC50

Effect conc.:

1.71 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: Yield

Remarks on result:

other: 95% confidence limits: 0.78 – 3.78 mg/l

Duration:

72 h

Dose descriptor:

other: EyC20

Effect conc.:

0.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: Yield

Remarks on result:

other: 95% confidence limits: 0.06 – 1.01 mg/l

Duration:

72 h

Dose descriptor:

other: EyC10

Effect conc.:

0.26 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: Yield

Remarks on result:

other: 95% confidence limits: 0.01 – 0.62 mg/l

Duration:

48 h

Dose descriptor:

other: EyC50

Effect conc.:

0.26 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: Yield

Remarks on result:

other: 95% confidence limits: 0.09 – 5.4 mg/l

Duration:

48 h

Dose descriptor:

other: EyC20

Effect conc.:

0.05 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: Yield

Remarks on result:

other: 95% confidence limits: 0.04 – 0.18 mg/l

Duration:

48 h

Dose descriptor:

other: EyC10

Effect conc.:

0.03 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: Yield

Remarks on result:

other: 95% confidence limits: 0.02 – 0.09 mg/l

Duration:

48 h

Dose descriptor:

other: ErC50

Effect conc.:

11.2 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% confidence limits: 7.47 - 17.7 mg/l

Duration:

48 h

Dose descriptor:

other: ErC20

Effect conc.:

0.28 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% confidence limits: 0.11 – 5.45 mg/l

Duration:

48 h

Dose descriptor:

other: ErC10

Effect conc.:

0.08 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Remarks on result:

other: 95% confidence limits: 0.05 – 0.3 mg/l

Details on results:

- Observation of abnormalities (for algal test): All cells appeared normal, no cells were observed that showed any morphological abnormalities
- Colour differences: In all concentrations at 24 hours the algae was observed to be normal. At 48 hours in 0.1, 0.32 and 1 mg/l the algae was normal and light green, in 3.2 mg/l the algae was observed to have few large cells and was light green and in 10 and 32 mg/l the algae was observed to have few large cells and was very light green. At 72 hours in 0.1, 0.32, 1 and 3.2 mg/l the algae was normal, green and light green. In 10 mg/l the algae was observed to be normal and very light green and in 32 mg/l it was normal and colourless.

Results with reference substance (positive control):

- Results with reference substance valid? Results were within the range given in the REACH document, Sep 2004 - ISO 8692 water quality

Reported statistics and error estimates:

Growth curved for each test concentration were plotted as logarithm of the mean cell density against time. The inhibition of growth was calculated using both the biomass (area under the growth curve) and the growth rate method. Where possible, the EC50 values were estimated graphically and 95% confidence limits calculated accordingly to the method of ToxCalcTM Version 5.0 ‘’Comprehensive Toxicity Data Analysis and Database Software’’, copyright 1994 - 1996.

- Test commissioned by: Miyoshi Oil and Fat Co., Ltd.

- Substance under test: Reaction products Epofloc L-1R (EC 939-782-1).

- Test species:Pseudokirchneriella subcapitata, strain CCAP 278/4

- Test type: Growth inhibition: 72 hour EC₅₀

- Test period: From 04 to 07 February 2014

- Test carried out at: Chemex Environmental International Limited, Unit J, Broad Lane Industrial Estate, Cottenham, Cambridge, CB24 8SW, UK

- Results:

 

Yield

0 - 48h E_yC₁₀: 0.03 mg/l (95% confidence limits: 0.02 - 0.09 mg/l)

0 - 48h E_yC₂₀: 0.05 mg/l (95% confidence limits: 0.04 - 0.18 mg/l)

0 - 48h E_yC₅₀: 0.26 mg/l (95% confidence limits: 0.09 - 5.4 mg/l)

0 - 72h E_yC₁₀: 0.26 mg/l (95% confidence limits: 0.01 - 0.62 mg/l)

0 - 72h E_yC₂₀: 0.50 mg/l (95% confidence limits: 0.06 - 1.01 mg/l)

0 - 72h E_yC₅₀: 1.71 mg/l (95% confidence limits: 0.78 - 3.78 mg/l)

0 - 72h NOEC: 0.32 mg/l

 

Growth rate

0 - 48h ErC₁₀: 0.08 mg/l (95% confidence limits: 0.05 - 0.30 mg/l)

0 - 48h ErC₂₀: 0.28 mg/l (95% confidence limits: 0.11 - 5.45 mg/l)

0 - 48h ErC₅₀: 11.2 mg/l (95% confidence limits: 7.47 - 17.7 mg/l)

0 - 72h ErC₁₀: 1.71 mg/l (95% confidence limits: 0.08 - 3.71 mg/l)

0 - 72h ErC₂₀: 3.03 mg/l (95% confidence limits: 0.38 - 5.63 mg/l)

0 - 72h ErC₅₀: 9.05 mg/l (95% confidence limits: 4.52 - 19.3 mg/l)

0 - 72h NOEC: 0.32 mg/l

Validity criteria fulfilled:

not specified

Conclusions:

The ErC50 72h value was estimated as 9.05 mg/l.

Description of key information

The ErC50 was determined to be 9.05 mg/l. The NOEC was found to be 0.32 mg/l

Key value for chemical safety assessment

EC50 for freshwater algae:

9.05 mg/L

EC10 or NOEC for freshwater algae:

0.32 mg/L