(±)-7-[(3-chloro-6,11-dihydro-6-methyldibenzo[c,f][1,2]thiazepin-11-yl)amino]heptanoic acid S,S-dioxide

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:

march 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.3 (Algal Inhibition test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

(±)-7-[(3-chloro-6,11-dihydro-6-methyldibenzo[c,f][1,2]thiazepin-11-yl)amino]heptanoic acid S,S-dioxide

EC Number:

276-851-9

EC Name:

(±)-7-[(3-chloro-6,11-dihydro-6-methyldibenzo[c,f][1,2]thiazepin-11-yl)amino]heptanoic acid S,S-dioxide

Cas Number:

72797-41-2

Molecular formula:

C21H25ClN2O4S

IUPAC Name:

(±)-7-[(3-chloro-6,11-dihydro-6-methyldibenzo[c,f][1,2]thiazepin-11-yl)amino]heptanoic acid S,S-dioxide

Test material form:

solid: crystalline

Details on test material:

White powder

Specific details on test material used for the study:

Batch 562371/016

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:

Strain : Chodat
Family : Chlorophyceaa
Order : Chlorococcales
Obtained in Dec 2009 from the institut fur Pflanzenphysiologie of Universitat Gottingen.
The Alga are kept as stock culture on solid agar at 8°C.

Study design

Test type:

not specified

Water media type:

freshwater

Total exposure duration:

72 h

Post exposure observation period:

0, 24, 48, 72h

Test conditions

Test temperature:

21.0 to 25.0°C

pH:

7.3 to 7.7

Details on test conditions:

light intensity : 6800 lux

Reference substance (positive control):

yes

Remarks:

Dichromate (CAS 7778-50-9)

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

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

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Effect concentrations 3

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

ca. 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Effect concentrations 4

Duration:

72 h

Dose descriptor:

NOEC

Effect conc.:

ca. 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 5

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 6

Duration:

72 h

Dose descriptor:

LOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

biomass

Details on results:

One valid main study was performed.
As the test item is poorly soluble in water, a saturated solution was prepared. this was done by shaking the nominal load with the appropriate amount of deionised water for 24 hours, followed by membrane filtration. The lower treatments were prepared by dilution of this saturated solution.
The study was performed using three concentrations containing 1, 10 and 100 mg/L.
The treatments were used to incubate the unicellular freshwater green alga Desmodesmus subspicatus for a period of 72 hours. The cell concentration of each replicate was determined by measuring the absorption of the cuvettes at 440 nm every 24 hours with a spectral photometer. With there measured values, the number of cells was calculated (linear correlation between cell concentration and adsorption given). Then the
growth rate, the area under the growth curve and the yield were determined.
The EC50s of potassium dichromate were tested in a current reference test. The values lay within the normal range of the laboratory.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The following results for the tests item were determined :
72h LOEC> 100mg/L (growth tae and biomass)
72h EC50 (growth rate and biomass) > 100mg/L
72h NOEC (growth rate and biomass) = 100 mg/L

Executive summary:

One valid main study was performed.

As the test item is poorly soluble in water, a saturated solution was prepared. this was done by shaking the nominal load with the appropriate amount of deionised water for 24 hours, followed by membrane filtration. The lower treatments were prepared by dilution of this saturated solution.

The study was performed using three concentrations containing 1, 10 and 100 mg/L.

The treatments were used to incubate the unicellular freshwater green alga Desmodesmus subspicatus for a period of 72 hours. The cell concentration of each replicate was determined by measuring the absorption of the cuvettes at 440 nm every 24 hours with a spectral photometer. With there measured values, the number of cells was calculated (linear correlation between cell concentration and adsorption given). Then the

growth rate, the area under the growth curve and the yield were determined.

The EC50s of potassium dichromate were tested in a current reference test. The values lay within the normal range of the laboratory.

The following results for the tests item were determined :

72h LOEC> 100mg/L (growth tae and biomass)

72h EC50 (growth rate and biomass) > 100mg/L

72h NOEC (growth rate and biomass) = 100 mg/L