Potassium nitrite

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:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Experimental test result performed according to the guideline.

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

Test solution was prepared by dissolving 1g of the test substance in 1L of ADaM’s media. Achieving test concentrations of 6.25mg/L,12.5mg/L, 25mg/L, 50mg/L,100mg/L, respectively.

Test organisms (species):

Daphnia magna

Details on test organisms:

- Common name: Water flea
- Source: Own breeding of daphnia magna
- Food: No feeding after hatching

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

24 and 48 hrs

Hardness:

153.5 mg of CaCO3

Test temperature:

21.2 ± 0.1°C

pH:

Control: 7.2
Test substance: 7.5

Dissolved oxygen:

7.1 mg/l

Nominal and measured concentrations:

6.25mg/L,12.5mg/L, 25mg/L, 50mg/L,100mg/L, nominal tets concentration used respectively.

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass beaker
- Aeration: No aeration during experiment
- Material, size, headspace, fill volume: 25 ml of glass beaker filled with 20 ml media having headspace of 5 ml
- No. of organisms per vessel: 10 daphnids

Test water:
ADaM’s media is used, prepared in MiliQ water.

OTHER TEST CONDITIONS
- Photoperiod:16 hours light and 8 hours dark

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : pH, Dissolved oxygen, temperature and mobility

- Results used to determine the conditions for the definitive study: Mobility

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Validity criteria fulfilled:

yes

Conclusions:

Based on the immobility of Daphnia magna due to the chemical exposure for 48 hours, the experimental median effective concentrations [EC-50 (48 h)] was determined to be > 100 mg/L. Based on the EC50 value, it can be consider that the chemical was nontoxic and hence, considered to be not classified as per the CLP classification criteria.

Executive summary:

Short term toxicity to aquatic invertebrate study was conducted for 96 hrs for assessing the effect of test chemical. Test conducted in accordance with OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test). Daphnia magna was used as a test organism. The stock solution was prepared by dissolving 1g of the test substance in 1L of ADaM’s media. Achieving test concentrations of 6.25mg/L, 12.5mg/L, 25mg/L, 50mg/L, 100mg/L, respectively was prepared from stock solution. 10 Daphnids was added per concentration. Test conducted under the static system at a temperature of 21.2 ± 0.1°C, hardness of 153.5 mg of CaCO3, dissolved oxygen of 7.1 mg/l and pH of 7.5, respectively for 48 hours. The effect of test chemical was calculated on the basis of immobility observations of Daphnia magna. Observations including (immobility, pH, Temperature, dissolved oxygen content) were recorded in the interval of 24 and 48 hours. After the exposure of test chemical with aquatic invertebrates Daphnia magna for 48 hours, immobility were observed and the EC50 value was determine to be > 100 mg/l. Based on the EC50 value, it can be consider that the chemical was nontoxic and hence, considered to be not classified as per the CLP classification criteria.

Description of key information

Short term toxicity to aquatic invertebrate study was conducted for 96 hrs for assessing the effect of test chemical. Test conducted in accordance with OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test). Daphnia magna was used as a test organism. The stock solution was prepared by dissolving 1g of the test substance in 1L of ADaM’s media. Achieving test concentrations of 6.25mg/L, 12.5mg/L, 25mg/L, 50mg/L, 100mg/L, respectively was prepared from stock solution. 10 Daphnids was added per concentration. Test conducted under the static system at a temperature of 21.2 ± 0.1°C, hardness of 153.5 mg of CaCO3, dissolved oxygen of 7.1 mg/l and pH of 7.5, respectively for 48 hours. The effect of test chemical was calculated on the basis of immobility observations of Daphnia magna. Observations including (immobility, pH, Temperature, dissolved oxygen content) were recorded in the interval of 24 and 48 hours. After the exposure of test chemical with aquatic invertebrates Daphnia magna for 48 hours, immobility were observed and the EC50 value was determine to be > 100 mg/l. Based on the EC50 value, it can be consider that the chemical was nontoxic and hence, considered to be not classified as per the CLP classification criteria.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L

Additional information

Experimental study of the target chemical and supporting weight of evidence study for its read across analogue were reviewed for short term toxicity to aquatic invertebrate endpoint which are summarized as below:

 

In an experimental weight of evidence study from study report, the short term toxicity to aquatic invertebrate study was conducted for 96 hrs for assessing the effect of test chemical. Test conducted in accordance with OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test). Daphnia magna was used as a test organism. The stock solution was prepared by dissolving 1g of the test substance in 1L of ADaM’s media. Achieving test concentrations of 6.25mg/L, 12.5mg/L, 25mg/L, 50mg/L, 100mg/L, respectively was prepared from stock solution. 10 Daphnids was added per concentration. Test conducted under the static system at a temperature of 21.2 ± 0.1°C, hardness of 153.5 mg of CaCO3, dissolved oxygen of 7.1 mg/l and pH of 7.5, respectively for 48 hours. The effect of test chemical was calculated on the basis of immobility observations of Daphnia magna. Observations including (immobility, pH, Temperature, dissolved oxygen content) were recorded in the interval of 24 and 48 hours. After the exposure of test chemical with aquatic invertebrates Daphnia magna for 48 hours, immobility were observed and the EC50 value was determine to be > 100 mg/l. Based on the EC50 value, it can be consider that the chemical was nontoxic and hence, considered to be not classified as per the CLP classification criteria.

 

For the test chemical from authoritative databases and secondary sources, short term toxicity to aquatic invertebrate study was carried out for 48 hrs for assessing the effect of test chemical. Test chemical concentrations were not verified analytically. Study was performed using Daphnia magna (Water flea) as a test organism under static conditions at a temperature of 21-25°C. Dilution water used in the study was glass-wool filtered University Lake water. On the basis of the effect on mobility of the test daphnids, the 48 hr LC50 value was determined to be 490 mg/l. Based on the LC50 value, it can be consider that the chemical was non-toxic and hence, considered to be not classified as per the CLP classification criteria.

 

In a supporting weight of evidence study, short term toxicity to aquatic invertebrate study was carried out for 48 hrs for assessing the effect of test chemical (Secondary source, 2000). Study was carried out in accordance with the DIN 38412 part 11. Test chemical concentrations were verified analytically. Analytical details was not specified in the published literature. Study was performed using Daphnia magna (Water flea) as a test organism under static conditions. On the basis of the effect on mobility of the test daphnids, the 48 hr EC0, EC50 and EC100 value was determined to be 587, 825 and 1010 mg/l, respectively. Based on the EC50 value, it can be consider that the chemical was non-toxic and hence, considered to be not classified as per the CLP classification criteria.

 

On the basis of the above results, test chemical was considered as non-toxic to aquatic invertebrates at environmental relevant concentrations and hence, considered to be 'not classified' as per the CLP classification criteria.