Barium nitrate

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

The justification for read across is attached in IUCLID Section 13.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

14.5 mg/L

Nominal / measured:

nominal

Conc. based on:

element (total fraction)

Remarks:

Ba

Basis for effect:

other: mortality including immobility

Remarks on result:

other: Biesinger and Christensen 1972

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

27.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (total fraction)

Remarks:

Ba(NO3)2

Basis for effect:

other: mortality including immobility

Remarks on result:

other: Biesinger and Christensen 1972

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

70.31 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (total fraction)

Remarks:

Ba

Basis for effect:

mobility

Remarks on result:

other: Lilius 1994

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

133.6 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (total fraction)

Remarks:

Ba(NO3)2

Basis for effect:

mobility

Remarks on result:

other: Lilius 1994

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

110 mg/L

Nominal / measured:

nominal

Conc. based on:

element (total fraction)

Remarks:

Ba

Basis for effect:

mobility

Remarks on result:

other: Calleja 1993

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

209 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat. (total fraction)

Remarks:

Ba(NO3)2

Basis for effect:

mobility

Remarks on result:

other: Calleja 1993

Reference 2

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:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Remarks:

Results are based on nominal values, and the test did not exactly follow existing guidance (1972-study), but the test method was well described and test conditions (e.g. test medium composition) were properly reported and monitored. The study should however be considered reliable with restrictions.

Principles of method if other than guideline:

Not a guideline study but meets generally accepted scientific standards and methodology is well documented and described.

GLP compliance:

not specified

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain: laboratory clone
- Source: University of Michigan
- Age at study initiation (mean and range, SD): 12h +/- 12h
- Feeding during test: no

ACCLIMATION
- Type and amount of food: 0.5 g of powdered dried grass and 10g of enriched trout-fry granules added to 250 mL of Lake Superior water and mixed vigorously in a blender for 5 minutes. This suspension was strained through #20 bolting cloth. The blender was then rinsed with an additional 50 mL of lake water, and the rinse water was added to the suspension. This suspension was stored in a refrigerator and mixed thoroughly each time an aliquot was withdrawn.
- Feeding frequency: 2 times a week for rearing and once weekly for testing

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

44-53 mg CaCO3/L

Test temperature:

18 +/- 1 °C

pH:

7.4-8.2

Dissolved oxygen:

+/- 9 mg O2/L

Salinity:

not reported

Nominal and measured concentrations:

nominal/measured test concentrations not reported: geometric series of 5-12 concentrations (not specified for Ba)

Details on test conditions:

No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): not reported

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Lake Superior water; unfiltered water strained through a #20 bolting cloth
- Metals: 14 µg Ba/L ; 16 µg Sr/L ; 0.78 µg Zn/L ; <0.5 µg Ni/L ; 1.51 µg Cu/L ; <0.5 µg Co/L ; < 0.01 g Hg/L ; < 0.1 µg Cd/L
- Chloride: 1.22 mg/L
- Alkalinity: 42.3 mg/L as CaCO3
- Ca: 13.7 mg /L
- Mg: 3.12 mg/L
- K: 0.53 mg/L
- Na: 1.13 mg/L

Reference substance (positive control):

no

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

14.5 mg/L

Nominal / measured:

nominal

Conc. based on:

element

Basis for effect:

other: mortality including immobility

Details on results:

no food was added during the test

Reported statistics and error estimates:

Results were statistically evaluated with the method of Litchfield and Wilcoxon (1949). LC50 was used for survival and represents an interpolation from three or more partial-effect concentrations.

Chemical characteristics of Lake Superior water were monitored during the testing period according to procedures outlined by the American Public Health Association and procedures employing atomic absorption spectroscopy.

Validity criteria fulfilled:

no

Conclusions:

Results are based on nominal values, and test did not exactly follow existing guidance (1972-study), but test method was well described and test conditions (eg., test medium composition) were properly reported. The 48-h LC50 for Daphnia magna was determined to be 14.5 mg Ba/L, based on nominal concentrations. Because no analytical monitoring of test item concentrations was performed, the study should be considered reliable with restrictions.

Reference 3

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

significant methodological deficiencies

Remarks:

The study was not considered reliable because no analytical monitoring of test substance concentrations was performed.

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

not specified

Analytical monitoring:

no

Test organisms (species):

Daphnia magna

Test type:

static

Water media type:

freshwater

Total exposure duration:

24 h

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

110 mg/L

Nominal / measured:

nominal

Conc. based on:

element

Remarks:

total Ba

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

209 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

Ba(NO3)2

Basis for effect:

mobility

Reported statistics and error estimates:

The 24-h L(E)C50s were calculated by the Trimmed Spearman-Karber method (Hamilton et al., 1977). The 5- and 15-min
EC50s of the Microtox ® test were obtained by the linear regression package provided by the Microbics Corporation (Mi-
crobics 1989).

Conclusions:

In this Microtox ® test, the 24-h EC50 for Daphnia magna was determined to be 110 mg Ba/L, equivalent to 209 mg Ba(NO3)2/L. No analytical verification of test item concentrations were performed.

Reference 4

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

significant methodological deficiencies

Remarks:

The study was not considered reliable because no analytical monitoring of test material concentrations was performed.

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

yes

Principles of method if other than guideline:

Acute toxicity tests were performed in Standard Reference Water (SRW; NaHC03 2.4 mM, K2S04 0.15 mM, CaCl2 2.0 mM, KH2P04 0.01 mM, pH 7.6) according to the OECD standard protocol (1980) with a few modifications. The tests were performed at 21 ± 1°C in 100 ml polystyrene vessels, with 50 ml liquid in each. Twenty neonates (< 24 h old) were introduced into vessels containing different concentrations of the test chemical and the vessels were closed with a polyethylene cap. There was no feeding and no aeration during the tests. Immobilization was determined visually after 3 and 24 h. For each chemical the test was repeated at least three times.

GLP compliance:

not specified

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain: not stated
- Source: obtained from the Department of Biology, University of Turku
- Feeding during test: no
- Food type: Scenedesmus algae every second or third day depending on the density of the culture

Test type:

static

Water media type:

freshwater

Total exposure duration:

24 h

Hardness:

200 mg CaCO3/L

Test temperature:

21°C

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 mL polystyrene vessels with 50 mL liquid each
- Type (delete if not applicable): closed with PE cap
- Material, size, headspace, fill volume: polystyrene
- Aeration: no
- No. of organisms per vessel: 20

TEST MEDIUM / WATER PARAMETERS
- Culture medium different from test medium: cultured in M4 media (Elendt and Bias, 1990)

OTHER TEST CONDITIONS
- Photoperiod: photoperiod of 12 h light and 12 h dark.

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): immobility

TEST CONCENTRATIONS
- Test concentrations: 5 concentrations used

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

70.31 mg/L

Nominal / measured:

nominal

Conc. based on:

element

Remarks:

total Ba

Basis for effect:

mobility

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

133.8 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

Ba(NO3)2

Basis for effect:

mobility

Reported statistics and error estimates:

For each chemical, five concentrations were used for the determination of EC50s. EC50 values were calculated using regression analysis after linearisation of the dose/ response curves by logarithmic transformation of the concentrations (statistical program; GraphPad 4).

Conclusions:

In this study, a 24-h EC50 value was reported of 70.31 mg Ba/L for Daphnia magna, equivalent to 133.8 mg Ba(NO3)2/L. Test concentrations were not measured.

Description of key information

A read across approach was followed to cover this endpoint. The key study is a study from Biesinger and Christensen (1972) for barium chloride. A 48-h LC50 of 14.5 mg Ba/L was reported for Daphnia magna. This result was recalculated to barium dinitrate based on the barium content of both substances (i.e. 27.6 mg barium trinitrate/L).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

14.5 mg/L

Additional information

Three studies are available containing relevant information for this endpoint. Two of these studies (Lilius et al., 1994 and Calleja et al., 1993) were performed with barium nitrate but were not considered reliable (Klimisch 3) and therefore only used as supporting evidence. The key study is a study from Biesinger and Christensen (1972) performed with the read across substance barium chloride. Results are based on nominal values, and the test did not exactly follow an existing guidance (1972-study), but the test method was well described and test conditions (e.g., test medium composition) were properly reported. A 48-h LC50 of 14.5 mg Ba/L was reported for Daphnia magna.