Sulphuric diamide

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:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2016

Report date:

2016

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Freshwater Alga and Cyanobacteria, Growth Inhibition Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Sulphuric diamide

EC Number:

232-262-9

EC Name:

Sulphuric diamide

Cas Number:

7803-58-9

Molecular formula:

H4N2O2S

IUPAC Name:

Sulphuric diamide

Test material form:

solid: crystalline

Specific details on test material used for the study:

Manufacturer: Anhui Shindo Chemical Co. LTD.Batch number: 0106A26 (A01151230)Physical state: Solid, crystalline substanceColour: WhiteStorage: In a dry place,

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

yes

Details on test solutions:

PREPARATION OF STOCK SOLUTIONThe preparation of stock and test solutions was based on the preliminary non GLP range finding test. For the stock solution 200.07 mg of test item was measured into 1 000 ml OECD medium. The suspension was stirred till complete dilution of test item. The stock solution was clear and colourless. The nominal concentration of the stock solution was 200 mg/L.PREPARATION OF TEST SOLUTIONSix test solutions of different concentration were prepared by mixing appropriate volume of OECD medium and stock solution of the test item. These concentrations were arranged in a geometric series with a maximum separation factor 2.0. The following table shows the preparation of test solutions. The volume of the prepared dilution levels was 300 ml except the control solution which was 600 ml.The alga inoculum culture was diluted 375 times so the initial alga cell concentration in every dilution and the control levels were 4 889 cells/ml.

Test organisms

Test organisms (species):

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

Details on test organisms:

Test species: Pseudokirchneriella subcapitata(Korshikov) F.Hindák(formerly known asSelenastrum capricornutum)Source: UTEX The Culture Collcetion of Algae (USA)

Study design

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

72 h

Test conditions

Test temperature:

The temperature inside the incubator at the test vessels was measured and registered continuously by Extech SD200 thermometer and datalogger. Throughout the test the temperature was nearly constant.

pH:

At the beginning of the test the pH values were measured in the remaining test solution of the concurrent test vessels at each dilution level. At the end of the test the pH values were measured in each test vessel. The pH of test solutions was not adjusted at the beginning of the test.

Nominal and measured concentrations:

In the test the following nominal concentrations were applied: 200; 160; 120; 80; 40 and 20 mg/L.

Details on test conditions:

Three replicates were prepared at every test and six at the control level. The vessels contained 75 ml test media. The test vessels were closed with silicone stopper and kept in incubator. For the proper mass transfer of carbon dioxide glass tubes with filter were placed trough silicone stoppers. The test was maintained under static conditions for a period of 72 hours. The temperature during the test remained in the 21 ± 2 °C range. The temperature data were harvested by Extech datalogger. The vessels were shaken and illuminated continuously in the incubator. The vessels were placed randomly into the incubator and were repositioned daily after sampling.

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

162.564 mg/L

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 2

Duration:

72 h

Dose descriptor:

EC20

Effect conc.:

214.48 mg/L

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 3

Duration:

72 h

Dose descriptor:

EC50

Remarks on result:

not determinable

Effect concentrations 4

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

102.283 mg/L

Conc. based on:

test mat.

Basis for effect:

other: yield

Effect concentrations 5

Duration:

72 h

Dose descriptor:

EC20

Effect conc.:

125.265 mg/L

Conc. based on:

test mat.

Basis for effect:

other: yield

Effect concentrations 6

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

184.6 mg/L

Conc. based on:

test mat.

Basis for effect:

other: yield

Details on results:

The ECx for specific growth rate and yield were determined by ToxRat® statistic software.

Applicant's summary and conclusion

Conclusions:

According to the Council Regulation (EC) 440/2008 Sulfamide is not hazardous to the aquatic environment. [72 hr EC50 (for algae or other aquatic plants) > 100 mg/L].