1,4:3,6-dianhydro-2,5-bis-O-(diphenoxyphosphoryl)-D-glucitol

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 with analytical concentration control

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2011

Report date:

2011

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

1,4:3,6-dianhydro-2,5-bis-O-(diphenoxyphosphoryl)-D-glucitol

EC Number:

935-211-5

Cas Number:

1305113-15-8

Molecular formula:

C30H28O10P2

IUPAC Name:

1,4:3,6-dianhydro-2,5-bis-O-(diphenoxyphosphoryl)-D-glucitol

Details on test material:

- Name of test material (as cited in study report): Isosorbid-O,O'-bis(diphenylphosphorsäureester)
- Physical state: solid
- Analytical purity: 97.9 Mol-%
- Storage condition of test material: ambient

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Sampling was performed at the start of the exposure (0 h) from the inoculated replicate 7 of each test group. At the end of the exposure (72 h) samples are taken from the combined inoculated replicates from each test group.
The samples were taken using a glass pipette and deposited into glass ampoules, which are rinsed with test solution before they are filled. Sample volume 20 mL

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
The test substance is poorly soluble in water. Therefore the test solution was prepared using a saturation column in order to achieve a saturated solution of the test substance. The saturation column was prepared by weighing approx. 200 mg of test substance into a weighing boat and dissolving it in approx. 200 mL dichloromethane. The solvent solution was then poured over the pre-cleaned quartz wool (approx. 20 g) in a stainless steel pan and the solvent was completely evaporated leaving the test substance adhered to the glass wool. The loaded quartz wool was rolled and packed into a glass column (50 cm long with 2.8 cm internal diameter) fitted with a plug of clean quartz wool to keep particulate matter in the column. Silicon stoppers fitted with short glass tubes were attached to the ends of the column, which was then connected to a peristaltic pump (Watson Marlow GMBH, Germany, 500 series) via a short length flexible tubing (Watson Marlow GmbH, Germany, Marprene). The packed column was rinsed with dilution water (column flow rate < 1 L/h) for about one day and the rinse water discarded.

The outflow of the column was introduced into a stock solution tank with an overflow. The stock solution (100%) was taken from the stock solution tank and used for preparation of the test treatment. All test vessels were allowed to saturate (for up to 7 days) with samples of test water collected and analysed to monitor test concentrations during this time. The 100% stock solution remained static and was replaced daily in the test vessels during the saturation period. Exposure was started once stable analytical results were obtained.

The exposure was started by adding inoculum culture at a ratio of 1:100 to the test solutions. The test solution after addition of algal inoculum is considered equivalent to the nominal concentration since no more than 1% dilution occurs.

Test organisms

Test organisms (species):

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

Details on test organisms:

TEST ORGANISM
- Strain: CHODAT (SAG 61.81)
- Source: Collection of algal cultures Inst. Plant Physiology, Göttingen, Germany; maintained continuously at the test facility
- Age of inoculum (at test initiation): 3 - 4 days, exponential growth phase

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Test conditions

Test temperature:

23.1 - 23.4 °C

pH:

7.1 - 8.8

Nominal and measured concentrations:

Nominal: 0.3 mg/L (and control)
Measured at 0 h (uninoculated): 0.136 mg/L
Measured at 0 h (inoculated): 0.136 mg/L
Measured at 72 h (uninoculated): 0.110 mg/L
Measured at 72 h (inoculated): 0.068 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Erlenmeyer flask (nominal volume 250 mL) plugged with gas permeable silicon sponge caps
- Initial cells density: 5000 cells/mL
- No. of vessels per concentration (replicates): 6
- No. of vessels per control (replicates): 6

GROWTH MEDIUM
- Standard medium used: yes

TEST MEDIUM / WATER PARAMETERS
- Culture medium different from test medium: no
- Intervals of water quality measurement: pH at the start and at the end; temperature continuously

OTHER TEST CONDITIONS
- Photoperiod: permanent illumination
- Light intensity and quality: ca. 4440 - 8880 lux (± 15%) , 400 - 700 nm, artificial light, type universal white

EFFECT PARAMETERS MEASURED
- Determination of cell concentrations: fluorescence using a Tecan Infinite 200Pro fluorometer; cell count in a Neubauer haemocytometer

TEST CONCENTRATIONS
- Range finding study
- Test concentrations: 100 mg/L
- Results used to determine the conditions for the definitive study: ErC50 > 100 mg/L

Reference substance (positive control):

yes

Remarks:

potassium dichromate (K2Cr2O7)

Results and discussion

Effect concentrations

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 0.096 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Remarks on result:

other: saturated solution

Details on results:

- A saturated solution was tested. No effects were observed within the range of solubility.

Results with reference substance (positive control):

EC50 = 0.96 mg/L (determined 2011-07-04)