Dibenzo[d,f][1,3,2]dioxaphosphepin, 6,6'-[[3,3',5,5'-tetrakis(1,1-dimethylethyl)[1,1'-biphenyl]-2,2'-diyl]bis(oxy)]bis-

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Details on test organisms:

-Test species and strain: Desmodesmus subspicatus CHODAT (SAG 86.81)
- Age (on study day 0): A stock algal culture is maintained continuously at the test facility. Before the exposure an inoculum culture is prepared from the stock culture and incubated for 3 days at 21 – 24 °C (max. temperature difference 2 °C). After this time, the inoculum culture is in exponential growth phase and can be used to initiate the test (study day 0).
- Supplier: Collection of algal cultures in University of Göttingen/Germany

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

Test temperature:

21.1 - 23.9

pH:

7.0 - 7.38

Nominal and measured concentrations:

The following loading rates were tested: 100, 31.6, 10.0, 3.17, 1.00 and 0.317 mg/L. Additionally a control was tested with test medium.

Details on test conditions:

TEST SYSTEM
Test procedure: static
Duration: 3 days (72 hours)
Initial cell density: 0.5 x 104 cells/mL
Illumination: continuously from the top, 68 – 96 μE×m-2×s-1
Culture flasks: 500 mL Erlenmeyer flasks with aluminium caps and two baffles
CO2 supply: by shaking on a rotating shaker, 105 rpm
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 6

GROWTH MEDIUM
- Standard medium used: yes

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 2

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 3

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

31.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Applicant's summary and conclusion

Validity criteria fulfilled:

yes