Potassium cyanate

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1980

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

other: Committee for toxicity testing, USEPA Report No. EPA-660/3-75-009 (1975)

Deviations:

not specified

GLP compliance:

not specified

Analytical monitoring:

yes

Details on sampling:

Sample concentrations were checked before and after the test.

Vehicle:

no

Details on test solutions:

reconstituted hard water

Test organisms (species):

Daphnia magna

Details on test organisms:

less than 24 h old

Test type:

static

Water media type:

freshwater

Total exposure duration:

48 h

Post exposure observation period:

no post exposure period

Hardness:

not indicated.

Test temperature:

not indicated.

pH:

not indicated.

Dissolved oxygen:

not indicated.

Salinity:

not indicated.

Nominal and measured concentrations:

Measured concentrations:
before test: 3.25, 5.49, 9.10, 14.87, 24.95 mg/L
after test: 3.20, 5.24, 9.03, 14.98, 24,89 mg/L

Details on test conditions:

30 organisms per concentration run as 3 replicate groups of 10 organisms.

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

18 mg/L

Nominal / measured:

not specified

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95 % CL: 15.2 - 24.2 mg/L

Details on results:

not indicated.

Results with reference substance (positive control):

no reference substance

Reported statistics and error estimates:

not indicated.

Validity criteria fulfilled:

not specified

Conclusions:

The LC50 for potassium cyanate after 48 h exposure to daphnia magna was determined to be 18 mg/L.

Executive summary:

The 48-hr acute toxicity of potassium cyanate to Daphnia magna was studied under static conditions. Daphnids were exposed to potassium cyanate at measured concentration of 3.25, 5.49, 9.10, 14.87, 24.95 mg/L (start of the test) for 48 hr. Mortality/immobilization and sublethal effects were observed at test termination. The 48-hour LC50/EC50 was 18 mg/L. This study is classified as acceptable and satisfies the guideline requirements (Committee for toxicity testing, USEPA) for an acute toxicity study with freshwater invertebrates.

Results Synopsis:

Test Organism Age: less than 24 h

Test Type: static

LC50: 18 mg/L 95 % C.I.: 15.2 to 24.2 mg/L

Description of key information

Only non-standard studies are available for potassium cyanate. The lowest LC50 identified was 18 mg/L in Daphnia magna.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

LC50

Effect concentration:

18 mg/L

Additional information

Key study:

- The 48-hr acute toxicity of potassium cyanate to Daphnia magna was studied under static conditions. Daphnids were exposed to potassium cyanate at measured concentration of 3.25, 5.49, 9.10, 14.87, 24.95 mg/L (start of the test) for 48 hr. Mortality/immobilization and sublethal effects were observed at test termination. The 48-hour LC50/EC50 was 18 mg/L. This study is classified as acceptable and satisfies the guideline requirements (Committee for toxicity testing, USEPA) for an acute toxicity study with freshwater invertebrates.

 

Supporting Study:

- The 48-hr acute toxicity of potassium cyanate to daphnia magna was studied under static conditions. Daphnids were exposed to potassium cyanate for 48 hr. Immobilization and sublethal effects were observed at test termination. Potassium cyanate showed a distinct toxicity on daphnia magna at a concentration of 23 mg/L. This study is classified as acceptable as supporting study.