Sodium nitrate

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

range finding: October 5 to 9, 2000

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on test solutions:

At test initiation, test solutions were prepared by diluting the appropriate amount of test substance into 15 L of dilution water in the test chamber. Nominal total product test concentrations of 6.25, 12.5, 25.0, 50.0, and 100 mg/L were prepared by diluting approximately 0.0938, 0.1875, 0.3750, 0.7500, and 1.5000 grams of the test substance, respectively. The test substance was stirred into solution with a glass rod. The dilution water control was prepared using only dilution water.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
Common name: Rainbow trout
- Strain: Oncorhynchus mykiss
- Source: obtained as fertilized eggs from Troutlodge, Inc., (Sumner, WA) and were reared for approximately five months prior to definitive test initiation.

ACCLIMATION
- Acclimation period: two-day acclimation period
- Acclimation conditions: Approximately 160 fish were removed from the holding tank and placed in acclimation. Acclimation water temperature ranged from 15.0 to 15.6°C.
- Feeding: fish were not fed during acclimation
- Health during acclimation (any mortality observed): no mortality was observed. No diseases were observed or treated during the holding period prior to test initiation.

Test type:

static

Water media type:

freshwater

Total exposure duration:

96 h

Hardness:

Total hardness 146 mg/L as CaCO3, total alkalinity 142 mg/L as CaCO3, and conductivity 310 µS/cm.

Test temperature:

14.6 to 15.4°C

pH:

7.56 to 8.12 in control and treatment solutions during the conduct of the definitive test

Dissolved oxygen:

Dissolved oxygen concentrations were equal to or greater than 9.22 mg/L (equal to or greater than 95% of saturation) at initiation of the definitive test. Dissolved oxygen concentrations ranged from 6.16 to 8.14 mg/L (64 to 84% of saturation) during the remainder of the definitive test.

Nominal and measured concentrations:

Nominal total product test concentrations of 6.25, 12.5, 25.0, 50.0, and 100 mg/L were prepared by diluting approximately 0.0938, 0.1875, 0.3750, 0.7500, and 1.5000 grams of the test substance, respectively.

Details on test conditions:

TEST SYSTEM
- Test vessel: 5-gallon glass jars containing 15 L of control or test solution and covered with clear plastic petri dish covers
- Material, size, headspace, fill volume: The glass jars had measurements of
approximately 47 cm (height) by 26 cm (inside-diameter) with 29 cm solution depth
- No. of organisms per vessel: each chamber contained its complement of five fish (or 10 fish
per treatment)
- No. of vessels per concentration (replicates):duplicate
- No. of vessels per control (replicates):duplicate
- No. of vessels per vehicle control (replicates): (one)
- Biomass loading rate: Instantaneous loading was calculated to be 0.35 g of fish tissue per liter of test solution.

OTHER TEST CONDITIONS
- Adjustment of pH:
- Photoperiod: Fluorescent lighting was maintained on a 16-hour daylight photoperiod with 30-minute simulated dawn and dusk periods.
- Light intensity: The light intensity was measured daily during the definitive test
and ranged from 512 to 526 lux. The light intensity was measured with a LI-COR Model LI-189 light meter equipped with a photometric sensor.

TEST CONCENTRATIONS
- Test concentrations: 0.0 (control), 0.1, 1.0, 10, and 100 mg/L (nominal)
- Results used to determine the conditions for the definitive study: Five fish were tested per treatment. No mortality or sublethal effects were observed in the control or any treatment level following 96-hours of exposure. Based upon the results of this test, nominal total product test concentrations of 6.25, 12.5, 25.0, 50.0, and 100 mg/L were selected for the definitive test.

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Nominal concentration confirmed by chemical analysis (>80% recovery)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks on result:

other: Nominal concentration confirmed by chemical analysis (>80% recovery)

Details on results:

- Mortality of control: 0%

All toxicity values were determined based on the mean calculated concentrations. No lethal or sublethal effects were noted at the highest concentration tested. Potassium sodium nitrate concentrations were calculated from total nitrate measurements. Measured total ammonium concentrations at the highest concentration tested were < 0.012 and 0.58 mg/L at test initiation and completion, respectively. Measured un-ionized ammonium concentration at the highest concentration tested were < 0.00039 and 0.0062 mg/L, respectively. The measured concentrations of both total and un-ionized ammonia for all control and treatment solutions were included as water quality parameters.

Reported statistics and error estimates:

Statistical analysis of the concentration versus effect data (mortality) was not performed due to the absence of mortality during the definitive test. The slope of the 96-hour dose-response line (log concentration vs. probit) could not be calculated due to the absence of fish mortality.

Validity criteria fulfilled:

yes

Conclusions:

No mortality or sublethal effects.
Nominal 96h-LC50 > 100 mg/L (confirmed by chemical analysis)
NOEC = 100 mg/L

Executive summary:

The acute toxicity of Potassium sodium nitrate to rainbow trout was investigated in a test according to OECD203 and GLP.

Test concentrations were confirmed by chemical analysis (nitrate measurements).

The nominal 96h-LC50 > 100 mg/L and the NOEC is 100 mg/L.

Reference 2

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

2008

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

The study was not carried out according to GLP and the concentrations were measured as nitrate-nitrogen with a HACH-Lange reagens kit, which is a method that is not very specific. Furthermore the specific nominal and measured test concentrations were not reported. To reduce reproductive behaviour, the photoperiod was 9:15 (light:dark), which deviates from the usual 16:8 cycle. However, it is well described in a peer-reviewed journal. Therefore it is considered reliable with restrictions and fit for use in a weight of evidence approach.

Qualifier:

according to guideline

Guideline:

other: ASTM E729-26 (1997) (Standard guide for conducting acute toxicity tests on test materials with fishes, macroinvertebrates and amphibians). In Annual Book of ASTM Standards, Vol. 11.05, West Conshohocken, PA, pp 220-240

Deviations:

not specified

GLP compliance:

no

Remarks:

The study was published in public literature and performed as a scientific experiment which does not need to comply with GLP.

Analytical monitoring:

yes

Details on sampling:

Concentrations were determined daily.

Vehicle:

no

Test organisms (species):

other: Topeka shiner (Notropis topeka)

Details on test organisms:

TEST ORGANISM
- Common name: Topeka shiner
- Source: Juvenile (~7 months) Topeka shiners were obtrained annually over a 3-year period from Lost Valley Fish Hatchery in Missouri, USA. They were held at appr. 12 °C in 1,500 L flow-through aerated holding tanks until the acclimation period. During the holding period, fish were fed frozen brown shrimp (Artemia salina) augmented with flake food once or twice daily.
- Age at study initiation: 19 months (juveniles), 32 months (adults)
- Length at study initiation: 46.3 ± 1.58 mm (juveniles); 66.2 ± 1.74 mm (adults)
- Weight at study initiation: Not determined
- Feeding during test: No

ACCLIMATION
- Acclimation period: Fish were acclimated to test temperatures in the holding tank. Food was withheld from the fish 24h prior to the test. The length of the acclimation period is not reported
- Acclimation conditions: same as test

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

210 - 230 mg/L (CaCO3)

Test temperature:

Juveniles: 24.5 ± 0.04 °C
Adults: 23.9 ± 0.04 °C

pH:

Juveniles: 8.26 ± 0.02
Adults: 8.26 ± 0.01

Dissolved oxygen:

> 6.0 mg/L

Nominal and measured concentrations:

Five concentrations and a control were tested in duplo. However, it is not reported what concentrations were tested.

Details on test conditions:

TEST SYSTEM
- Test vessel: Aquaria with a stainless steel screen at one end maintaining water depth at 22 cm
- Material: Not reported
- Dimensions: 50 x 25 x 30cm
- Fill volume: 27.5 L
- Aeration:
- Type of flow-through (e.g. peristaltic or proportional diluter): Peristaltic diluter
- Renewal rate of test solution (frequency/flow rate): 6 - 7 times per day
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates):2
- No. of vessels per control (replicates): 2
- Biomass loading rate: Unknown (weight of fish not reported)

TEST MEDIUM / WATER PARAMETERS
- Source: A deep well (not further specified), total alkalinity, chloride concentration and pH were recorded

OTHER TEST CONDITIONS
- Adjustment of pH: No
- Photoperiod: 9:15 (light dark) to reduce reproductive behaviour
- Light intensity: Not reported

EFFECT PARAMETERS MEASURED :Mortality (every 12h)

TEST CONCENTRATIONS
No information provided on test concentrations

Reference substance (positive control):

not specified

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

1 559 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

other: NO3-N

Basis for effect:

mortality (fish)

Remarks on result:

other: Adult (32 months), median measured concentration, 95% CI 1412 - 1720 mg/L

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

1 354 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

other: NO3-N

Basis for effect:

mortality (fish)

Remarks on result:

other: Juvenile (19 months), median measured concentration, 95% CI 1275 - 1437 mg/L

Details on results:

No mortality was observed in the control.

Validity criteria fulfilled:

not specified

Conclusions:

The median measured 96h LC50 value to adult (32 months old) Topeka shiners of sodium nitrate (measured as NO3-N) was 1559 mg/L.
The median measured 96h LC50 value to juvenile (19 months old) Topeka shiners of sodium nitrate (measured as NO3-N) was 1354 mg/L.

Reference 3

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

non GLP, no analytical monitoring

Qualifier:

no guideline followed

Principles of method if other than guideline:

No Data

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

not specified

Test organisms (species):

Lepomis macrochirus

Details on test organisms:

TEST ORGANISM
- Common name: common bluegill
- Strain: Lepomis macrochirus Rafinesque
- Source: from private fish hatchery Maryland, USA
- Length at study initiation (length definition, mean, range and SD): 5-9 cm
- Weight at study initiation (mean and range, SD): 1-9 gram
- Feeding during test: no

ACCLIMATION
- Acclimation period: 7 days
- Acclimation conditions (same as test or not): same as test, but in a large aquarium
- Type and amount of food:
- Food type: chopped, freshly cooked, shrimp
- Frequency: daily during acclimatisation period, no feeding in the 43 hours preceeding a test, nor during the test period.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

45 - 50 ppm CaCO3

Test temperature:

19-21 degrees Celsius

pH:

7.2 -8.8

Dissolved oxygen:

4.1-6.6 ppm

Nominal and measured concentrations:

10,000 mg/L
11,500 mg/L
12,000 mg/L
12,500 mg/L
13,500 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: five-gallon Pyrex jars
- Type (delete if not applicable): closed, rubber stoppers
- Material, size, headspace, fill volume: voume 20.4 liter
- Aeration: through aeration tube 7mm in outside diameter, Compressed air at a rate of approx. 160 bubbles per minute was forced through the water over the 96-hour test period.
- Renewal rate of test solution (frequency/flow rate): no renewal
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates):1

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Chu12, modified was prepared from distilled water and analytical or reagent grade chemicals:
KCL and Na2SiO3 at 0.02 g/L,
NaHCO3 and MgSO4.7H2O at 0.04 g/L,
Ca(NO3)2 at 0.03 g/L
CaCO3 at 0.01 g/L
K2HPO4 at 0.002 g/L
Ferric citrate-citric acid at 0.004 g Fe 3+/L

OTHER TEST CONDITIONS
- Adjustment of pH:no
- Photoperiod: no data

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- mortality (criteria cessation of gill movement, and lack of response to a mechanical stimulus for a period of 5 minutes)

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

12 000 mg/L

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Details on results:

- Mortality of control: none
- Survival 96h at 10,000 mg/L = 100/100%
- Survival 96h at 11,500 mg/L = 80/80%
- Survival 96h at 12,000 mg/L = 50/50%
- Survival 96h at 12,500 mg/L = 20/20%
- Survival 96h at 13,500 mg/L = 0/0%

Validity criteria fulfilled:

not applicable

Conclusions:

LC50 at 96h = 12,000 mg/L

Reference 4

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

no GLP, no analytical measurement

Qualifier:

no guideline followed

Principles of method if other than guideline:

No data

GLP compliance:

no

Specific details on test material used for the study:

Test material is stated to be pure.

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Gambusia affinis

Details on test organisms:

TEST ORGANISM
- Common name: Western mosquitofish
- Source: wild caught from Stillwater Creek, Payne County, Oklohama, USA (turbid habitat)
- Age at study initiation (mean and range, SD): adult females, unknown weight and size
- Feeding during test
- Food type: plankton and detritus (collected locally) and various artificial foods
- Frequency: fed as necessary to maintain a healthy condition

ACCLIMATION
- Acclimation period: 2-3 weeks

Treatment
- terramycin was added regularly for prevention of tail-rot disease

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Post exposure observation period:

24, 48, 72 and 96hr

Hardness:

no data

Test temperature:

19-20 degrees Celsius

pH:

7.8-8.3 for test medium
7.0-7.3 after addition of the chemical

Dissolved oxygen:

artificial aeration

Salinity:

no data

Nominal and measured concentrations:

series of concentrations from 10 to 18,000 ppm, with a constant factor of 1.8

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type : cylindrical jars
- Material, size, headspace, fill volume: pyrex jars 12 inch high, 12 inch in diameter, 15 liter
- Aeration: artificial aeration to maintain the oygen level
- Renewal rate of test solution : water was not replaced
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1

TEST MEDIUM / WATER PARAMETERS
- Source of dilution water: water obtained from two farm ponds, high turbidity
- Alkalinity: relatively low alkalinity (usually less than 100 ppm of methyl orange alkalinity)

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- survival scored at 24, 28, 72, 96 hr

Duration:

24 h

Dose descriptor:

LC50

Effect conc.:

11 800 mg/L

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

10 000 mg/L

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

6 650 mg/L

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Details on results:

The LC50 equals the Median Tolerance Limit TLm, which is defined as the concentration at which 50% of organisms would be expected to survive.

Sublethal observations / clinical signs:

-Nominal concentrations (mg/L): ranging from 10 to 18000 mg/L differing with a constant factor of 1.8

-Mortality: 0 /10 (up to 1800 mg/L), 1/10 (3200 mg/L), 7/10 (5600 mg/L) and 10/10 (10000 and 18000 mg/L)

-Other effects: turbidity at 0/96 hr 280/250 mg/L.

-Effect concentration vs. test substance solubility: solubility (based on precipitation) higher than effect concentration.

-Dose related effects: mortality.

Validity criteria fulfilled:

not applicable

Conclusions:

Median Tolerance Limit TLm 24h is 11,800 mg/L
Median Tolerance Limit TLm 48h is 10,000 mg/L
Median Tolerance Limit TLm 96h is 6,650 mg/L

Reference 5

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

non GLP, no analytical monitoring

Qualifier:

no guideline followed

Principles of method if other than guideline:

Both freswater and salt water were tested.
Standard bioassay methods as outlined by American Public Health Association were followed. 

GLP compliance:

not specified

Analytical monitoring:

not specified

Vehicle:

no

Test organisms (species):

Salmo sp.

Details on test organisms:

TEST ORGANISM
- Common name: Chinook and rainbow trout (Salmo gairdneri)
- Source: Chinook fingerlings from Marine Experiment Station and Rainbow trout fingerlings from Rhode Island State Trout Hatchery, Perryville, USA
- Weight and Length at study initiation:
Chinook freshwater: 0.978-9.66 g, 52-95 mm
Chinook 15 0/00: 2.733-9.89 g, 67-100 mm
Trout freshwater: 1.154-5.15 g, 52-80 mm
Trout 15 0/00: 2.00-21.0 g, 76-115 mm

- Feeding during test: no data

ACCLIMATION: no data

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Remarks on exposure duration:

and 7 or 10 days

Hardness:

no data

Test temperature:

13-16.8 degrees Celsius

pH:

no data

Dissolved oxygen:

compressed air was supplied to saturation

Salinity:

salinity in salt water experiments was 15 ppt

Details on test conditions:

TEST SYSTEM
- Aeration: compressed air supplied to saturation
- Renewal rate of test solution (frequency/flow rate): at the end of 96 hours
- No. of organisms per vessel: 10
- No. of organisms per concentration: 16-23 on avergae for 96hr assessment, 12-24 for 7 or 10-day assessment
- No. of vessels per control (replicates): 1

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of freshwater: using reconstituted deionized water
- Source/preparation of 15ppt salinity water: using Instant Ocean 9Aquarium Systems Inc., Eastlake, Ohio, USA)

OTHER TEST CONDITIONS
- Adjustment of pH: no data
- Photoperiod: no data

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
- mortality

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

5 800 other: mg NO3- per liter

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Remarks:

chinook freshwater

Remarks on result:

other: 95% CL: 5087-6612

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

4 400 other: mg NO3- per liter

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Remarks:

Chinouk saltwater

Remarks on result:

other: 95% CL: 4151-4664

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

6 000 other: mg NO3- per liter

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Remarks:

Rainbow trout freshwater

Remarks on result:

other: 95% CL: 5768-6240

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

4 650 other: mg NO3- per liter

Nominal / measured:

nominal

Basis for effect:

mortality (fish)

Remarks:

Rainbow trout salt water

Remarks on result:

other: 95% CL: 4402-4901

Reported statistics and error estimates:

median tolerance limits (TLm) and confidence limits determined according to Litchfield and Wilcoxon.
TLm values were considered to be equal to LC50.
Pairwise comparison of TLm values

Validity criteria fulfilled:

yes

Conclusions:

LC50 (96-h; freshwater, chinook) = 5,800 mg NO3/L
LC50 (96-h; 15 ppt salinity, chinook) = 4,400 mg NO3/L
LC50 (96-h; freshwater, rainbow trout) = 6,000 mg NO3/L (=8226 mg NaNo3/L)
LC50 (96-h; 15 ppt salinity, rainbow trout) = 4,650 mg NO3/L

Description of key information

In studies with sodium nitrate it appeared that the substance has a high 96 hr LC50 for fish (all >1000  mg/L). Based on a reliable guideline study, sodium potassium nitrate appeared to have an LC50> 100 mg/l.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

1 354 mg/L

Marine water fish

Marine water fish

Effect concentration:

4 400 mg/L

Additional information

Several studies with sodium nitrate itself were present, which are all supporting eachother in the fact that sodium nitrate has a high 96 hr LC50 for fish. Common bleugill LC50 was 12000 mg/L, fresh and saltwater studies with chinook and rainbow trout showed a lowest 96 hr LC50 of 4400 mg/L (based on NO3 -), freshwater Gambusia affinis 96 hr LC50 was determined to be 6650 mg/L. The 96h LC50 to juvenile (19 months old) Topeka shiner was determined to be 1354 mg/L (as NO3 -N). In addition, based on a reliable guideline study OECD 203, sodium potassium nitrate appeared to have a nominal LC50> 100 mg/L (confirmed by chemical analysis) in rainbow trout.