Fatty acids, C8-10, diesters with 1,4:3,6-dianhydro-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

Study period:

from 01/09/08 to 04/11/08

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2008

Report date:

2008

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Isosorbide Diesters

EC Number:

700-073-5

Cas Number:

1215036-04-6

Molecular formula:

As it is an UVCB, we can not provide the exact molecular formula.

IUPAC Name:

Isosorbide Diesters

Details on test material:

Identification
Product name: LAB 3822
CAS number: /
Batch number: FAL 07/25
III - 2 - Characteristics
Composition: Di-ester dianhydrohexitol : 87% (w/w)
Molecular Formula: C24H42O6
Molecular weight: 426 g.mol-1
Percentage of carbon: 67.6%
Mono-ester dianhydrohexitol: 11%
Residual organic acids: 0.5%
Water: 0.1%
Percentage of carbon: 65.4% (determination by carbon analyser)
Melting point: not applicable
Boiling point: 374.6°C
Vapor pressure at 25°C: 0.03Pa
Solubility: very weak in water ; miscible in ethanol and DMSO
Expiry date: March 2009 (according to analysis certificate of 19/07/2007)
Storage conditions: at room temperature but preferably between 10 and 15°C

Test solutions

Vehicle:

no

Details on test solutions:

The LAB 3822 is slightly soluble in water but no solubility value is specified by the
sponsor.
In order to test the dissolved part of the test item, a stock solution at 500 mg/L was
prepared, for each renewal, in growth medium as follows:
Ultrasonication during 10 minutes
Magnetic stirring during 10 minutes
Centrifugation for 30 minutes (3000 g)
The stock solution was then diluted in growth medium to get the appropriate nominal
initial concentrations.
The test solutions were renewed after a period of 24 hours.

Test organisms

Test organisms (species):

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

Details on test organisms:

Pseudokirchneriella subcapitata, green algae belonging to the order of Chlorococcales
(previously named Selenastrum capricornutum and Raphidocelis subcapitata),
Strain: CCAP 278/4
Liquid culture of Pseudokirchneriella subcapitata was obtained from the Culture Center for
Algae and Protozoa (CCAP) Institute of Freshwater Ecology, Ferry House, Ambleside,
Cumbria, U.K.
Vessels: 250 ml conical flasks with air permeable stoppers filled with 100 ml of test
solution.
Number of replicates: 3
Test concentrations: 20.7 – 45.5 – 100.0 – 220.0 and 484.0 mg/L (nominal concentrations)
Controls: 6 static controls, 6 semi – static controls.
Negative controls: one for each test concentration ( test solution without algae).
Initial cell concentration: 104 cells/ mL taken from an exponentially growing preculture.
Aeration: none.
Renewal of test solutions: every 24 hours, algal cells are collected by centrifuging the test
solutions and resuspended in the test solution freshly prepared
Determination of the algal cells concentration: every 24 hours, before renewal, a volume
of 2 mL has been sampled before centrifugation in order to determine cells concentration.
This has been done by measuring alga cells number with a counter coulter and test solution
fluorescence using a microplate fluorimeter (excitation: 438 nm, emission: 685 nm).
Environmental conditions : flasks incubated within the range 23 – 25°C under continuous
illumination (white light, intensity within the range 6350 – 7630 lux) and constantly shaken
(125 rpm).
Duration: 72 hours

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

72 h

Test conditions

pH:

7.9

Results and discussion

Effect concentrations

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

172.2 mg/L

Nominal / measured:

nominal

Basis for effect:

growth rate

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

The biomass in the control cultures (semi-static) increased by a factor of more than 16, corresponding to a specific growth rate of 0.92 day-1(mean cell density at T 0h: 104 cell/.mL ; mean cell density at T 72h: 116.43 104 cell/mL). The mean coefficient

Conclusions:

In semi – static conditions, an ErC 50 (0 – 72 h) of 172.2 mg/L (nominal concentration) has been determined.

Executive summary:

TEST PURPOSE Determination, under defined conditions, of the effects of the test item on the growth of the unicellular green algal species: Pseudokirchneriella subcapitata.

GUIDELINE Updated OECD guidelines for testing of chemicals, n°201 (Adopted 23 March 2006): Freshwater Alga and Cyanobacteria, Growth Inhibition Test.

TEST SYSTEM Pseudokirchneriella subcapitata

TEST ITEM LAB 3822

TEST CONCENTRATIONS 20.7 – 45.5 – 100.0 – 220.0 and 484.0 mg/L (in nominal concentrations)

DURATION 72 hours (semi-static conditions, renewal every 24 hours)

RESULTS

ErC 10 (0 – 72 h): 11.3 mg/L (5.2 – 21.1 mg/L)

ErC 50 (0 – 72 h): 172.2 mg/L (133.5 – 217.5 mg/L)