Sodium nitrate

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

No GLP and no analytical monitoring.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

yes

Remarks:

duration only 24 hours, no analytics

Principles of method if other than guideline:

test duration 24h, no analytical verification

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

Stock solution prepared 10000 mg/l.
Dilutions were made from stock.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Strain: Daphnia magna straus
- Source: Institut National de Recherche Chimique Appliquee, France
- Age at study initiation: 6-24h
- Feeding during test: no

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

24 h

Hardness:

2.55 mmol/l

Test temperature:

292-294 K

pH:

8.1

Nominal and measured concentrations:

905, 1280, 1810, 2560, 3620, 5120, 7240, 10239 mg/l

Details on test conditions:

TEST SYSTEM
- Test vessel: 10 ml
- Aeration: none
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates):4

OTHER TEST CONDITIONS
- Photoperiod:16h
- Light intensity: 5 Mikroeinstein (400-750 nm)

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : immobilized daphnids at 0 and 24 h

Key result

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

8 609 mg/L

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

EC0

Effect conc.:

7 240 mg/L

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

EC100

Effect conc.:

10 239 mg/L

Basis for effect:

mobility

Conclusions:

Sodium nitrate did not induce acute immobilisation of Daphnia magna up to 7240 mg/l after 24 hours of exposure (EC 0). EC50 was 8609 mg/l after 24 h.

Description of key information

A 24h EC50 of 8600 mg/L  has been derived for sodium nitrate in a reliable OECD 202 guideline study with daphnia magna.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

8 600 mg/L

Additional information

Several studies with invertebrates are present with sodium nitrate, all showing very high EC50s. In a reliable OECD 202 guideline study with daphnia magna, the 24 hr EC50 was determined to be 8600 mg/L. In another study a 48 hr EC50 was derived to be 3581 mg/L, although limited information on materials and methods was available, but supporting the 24 hr EC50. Studies with other invertebrates showed results expressed as NO3 -, EC50s being >100 or >1000 mg/L.