2H-Tetrazol-5-amine, potassium salt (1:1)

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Report date:

2009

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

yes

Remarks:

The temperature for the main study lay in a range of 23.0 to 24.8 °C (test item and positive control). As no significant immobility occurred during the test, this deviation was stated as uncritical.

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

potassium 5-amino-1H-1,2,3,4-tetrazol-1-ide

Cas Number:

136369-04-5

Molecular formula:

CH2KN5

IUPAC Name:

potassium 5-amino-1H-1,2,3,4-tetrazol-1-ide

Test material form:

solid: particulate/powder

Details on test material:

Batch no.: 08KI030

Sampling and analysis

Analytical monitoring:

yes

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

Daphnia magna is bred in the LAUS GmbH throughout the year. The animals are kept for the use in toxicity tests. They multiply by parthenogenesis, thus being genetically identical. The holding is performed similar to the method described in EN ISO 6341, following SOP 115 002 01 („Zucht und Hälterung von Daphnia magna STRAUS“), edition 9, adopted 27. Apr. 2007.

Study design

Test type:

static

Water media type:

freshwater

Total exposure duration:

48 h

Test conditions

Hardness:

Resulting hardness in mmol/L: 2.50
Resulting hardness in mg CaCO3/L: 250

Test temperature:

23 - 24.8 °C

pH:

7.7 +- 0.2

Dissolved oxygen:

7.3 - 8.6 mg/L

Nominal and measured concentrations:

Nominal: 1.0 / 2.2 / 4.6 / 10 / 22 / 46 / 100 mg/L.
The measured concentrations showed very good correlation with the nominal concentrations. The recovery rate after 48 hours was in a range of 97 % - 101 % of the start concentration. The measured concentrations were in a range of 100 % - 103 % of the nominal concentration. Therefore the determination of the biological results was based on the nominal concentration.

Reference substance (positive control):

yes

Remarks:

potassium dichromate (0.5 / 0.625 / 1.0 / 1.25 / 1.5 / 2.0 / 2.5 / 3.0 mg/L)

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

24 h

Dose descriptor:

NOEC

Effect conc.:

10 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

other: immobilisation

Effect concentrations 2

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

4.6 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

other: immobilisation

Effect concentrations 3

Key result

Duration:

24 h

Dose descriptor:

other: EC50i

Effect conc.:

49 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

other: immobilisation

Effect concentrations 4

Key result

Duration:

48 h

Dose descriptor:

other: EC50i

Effect conc.:

13 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

other: immobilisation

Results with reference substance (positive control):

The 24h-EC50i of potassium dichromate was determined as 1.6 mg/L, lying within the demanded range of 0.6 – 1.7 mg/L.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

All validity criteria were met. For the estimation of the EC50s of test item and positive control, the fits showed sufficient statistical correspondence of the data with the doseresponse- equation. The 24h-EC50i of potassium dichromate was determined as 1.6 mg/L, lying within the demanded range of 0.6 – 1.7 mg/L. The analytical determinations of the test item showed very good correlation between nominal and measured concentrations and very good recovery rates. Therefore, the test item 5-Aminotetrazol Potassium can be stated as stable under the test conditions and the determination of the results was based on the nominal concentrations. The result of the test can be considered valid. The following results were determined for the test item 5-Aminotetrazol Potassium (species: Daphnia magna): 24h-NOEC = 10 mg/L, 48h-NOEC = 4.6 mg/L, 24h-EC50i = 49 mg/L, 48h-EC50i = 13 mg/L.

Executive summary:

The main study was performed using seven concentrations ranging from 1 to 100 mg/L. Twenty daphnia were exposed to the test item for 48 hours in a static test system. After 24 and 48 hours, the immobilised daphnia were counted. Four concentrations showed toxicity between 55 and 90% immobilisation. Two of the animals (10 %) were immobilised in the control. The 24h-EC50i of potassium dichromate was tested in a current reference test. The value was determined as 1.6 mg/L, lying within the demanded range of 0.6 – 2.1 mg/L. At the beginning and at the end of the test, the content of the test item in the test solutions was determined using HPLC. The recovery after 48 hours ranged from 97 to 102 % of the start concentration. The correlation between nominal and measured concentration was 100% - 103 % at the beginning and 100 – 102 % at the end. Therefore, the determination of the biological results was based on the nominal concentration. The following results were determined for the test item 5-Aminotetrazol Potassium (species: Daphnia magna): 24h-NOEC = 10 mg/L, 48h-NOEC = 4.6 mg/L, 24h-EC50i = 49 mg/L, 48h-EC50i = 13 mg/L.