Potassium carbamoylcarbamate

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2012-01-16 to 2012-11-13

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study conducted per OECD 202

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

GLP compliance:

yes

Remarks:

Only Exceptions: Lastest water characterization in Feb 2012 and test substance characterization not performed in accordance to GLP.

Test material

Test material information

1

Reference substance name:

Potassium carbamoylcarbamate

EC Number:

247-728-7

EC Name:

Potassium carbamoylcarbamate

Cas Number:

26479-35-6

Molecular formula:

C2H3KN2O3

IUPAC Name:

potassium N-carbamoylcarbamate

Test material form:

solid: particulate/powder

Remarks:

migrated information: particulates

Details on test material:

- Name of test material (as cited in study report):Potassium Allophonate
- Physical state:powder
- Analytical purity:83.8%

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
N/A

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Test solutions were sampled at 0 and 24 hours for fresh solution and 24 and 48 hours on spent solution. For each sampling a 10-mL sample was collected and diluted as necessary with 80:20 acetonitrile:water to provide final concentrations within the analytical standard range of 0.0250 to 1.25 ug a.i./mL. Analytical standards were prepared by diluting volumes of primary stock (1.15 mg a.i./mL) with 80:20 acetonitrile:HPLC water.

Test solutions

Vehicle:

no

Details on test solutions:

A primary standard of .10 mg a.i./L was prepared by diluting 0.237 g (0.2000 adjusted for purity) potassium allophonate to a volume of 1000mL. This standard was used as the highest concentration. Appropriate volumes of the primary standard were diluted up to 1.0 L with dilution water to prepare the 6.3, 13, 25, and 50 mg a.i./L test concentrations. The control was dilution water only.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Source: ABC laboratories In-house culture
- Age at study initiation (mean and range, SD): <24 hrs
- Feeding during test: None
- Food type: In culture; P. subcapitata and wheat grass/salmon starter/yeast blend
- Frequency: In culture; Daily

ACCLIMATION
- Acclimation period: None

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

N/A

Test conditions

Hardness:

142 CaCO3/L

Test temperature:

19.5 to 20.2 degree C

pH:

8.5 to 8.7

Dissolved oxygen:

8.5 to 8.8 on fresh solutions
8.6 to 8.8 on spent solutions

Salinity:

N/A

Nominal and measured concentrations:

Nominal: 0 (control), 6.3, 13, 25, 50, 100 mg a.i./L
Mean Measured:

Details on test conditions:

TEST SYSTEM
- Test vessel: 250 ml glass jars with cover
- Fill volume: 200 ml
- Aeration: None
- Renewal rate of test solution (frequency/flow rate): Daily
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Moderately hard freshwater
- Alkalinity: 154 CaCO3/L
- Conductivity: 341 uS
- Culture medium different from test medium: No
- Intervals of water quality measurement: Total hardness, total alkalinity, and conductivity measured at test initiation. Temperature, dissolved oxygen and pH were measured daily

OTHER TEST CONDITIONS
- Adjustment of pH: None
- Photoperiod: 16 hr daylight photoperiod with 30 minute dawn and dusk periods
- Light intensity: 729 lux

EFFECTS Measured: Immobility within 15 seconds after gentle agitation of test chamber or organism itself

TEST CONCENTRATIONS
- Range finding study: Yes
- Range finding concentrations: 0, 0.1, 1.0, 10 and 100 mg a.i./L
- Results used to determine the conditions for the definitive study: No mortality or immobility in any test concentration

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 88.4 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 88.4 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 3

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

40.7 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

At initiation, measured potassium allophonate concentrations were 95 - 107% of nominal concentrations. At 24 hrs, measured concentrations in fresh solution were 94 - 150% of the nominal concentrations. At 24 and 48hrs, measured concentrations in spent solution were 50 - 95% of the nominal concentrations. The mean measured concentrations throughout the 48 hr exposure were 5.26, 13.9, 23.4, 40.7 and 88.4 mg a.i./L.

After 48 hrs, immobility was 0, 5, 5, 0, 5 and 15% in the 0, 5.26, 13.9, 23.4, 40.7 and 88.4 mg a.i./L treatments respectively. Therefore, the 24- and 48- Hr EC50 was >88.4 mg a.i./L and the NOEC was 40.7 mg a.i./L. No sublethal effects were reported and the 48- Hr concentration-response curve could not be calculated.

Results with reference substance (positive control):

N/A

Reported statistics and error estimates:

EC50 estimates were calculated by probit, Trimmed Spearman-Karber, or Spearman-Karber method with SAS software (Version 9.1). NOEC was determined using a Dunnett's test. No 95% confidence limits could be deteremined.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The D. magna 24- and 48- Hr EC50 for potassium allophonate is >88.4 mg a.i./L, the highest concentration tested. Immobility occured in 15% of the organisms at a concentration of 88.4 mg a.i./L, leading to a NOEC at 40.7 mg a.i./L.