Barium bis(dihydrogenorthophosphate)

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:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Publication is acceptable for assessment. Test method is well described. Test substance concentration not given.

Principles of method if other than guideline:

The acute toxicity of Barium chloride dihydrate to Daphnia magna was tested by exposing daphnids to the substance for 48 hours in a static system.

GLP compliance:

not specified

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Source: bred at testing laboratory, originally obtained from the University of Michigan,
- Age at study initiation (mean and range, SD): 12 ± 12 h
Feeding during test: yes
- Type of food: 0.5 g of powdered dried grass and 10g of enriched trout-fry granules to 250 mL of Lake Superior water and mixed vigorously in a blender for 5 minutes.

ACCLIMATION
- Type and amount of food: food suspension comprising powdered dried grass and enriched trout-fry granules.
- Feeding frequency: twice weekly during rearing

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

45.3 mg/L

Test temperature:

18 ± 1 °C

Dissolved oxygen:

Dissolved oxygen concentrations in test containers were near saturation at all times.

Details on test conditions:

TEST SYSTEM
- Test vessel: test chambers
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Lake Superior water, Ba concentration: Barium 0.01 mg/L
- Chlorine: 1.2 mg/L
- Alkalinity: 42.3 mg/L
- Ca/mg ratio: 13.7/3.1 mg/L


OTHER TEST CONDITIONS
- Photoperiod:16:8 h
- Light intensity: 115 ft-c

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

14.5 mg/L

Nominal / measured:

nominal

Conc. based on:

element

Remarks:

Barium

Basis for effect:

mortality

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

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

Adequacy of study:

weight of evidence

Justification for type of information:

Please refer to the analogue justification attached to chapter 13

Reason / purpose for cross-reference:

read-across source

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

14.5 mg/L

Nominal / measured:

nominal

Conc. based on:

element

Remarks:

Barium

Additional information

Data on the acute toxicity of barium bis(dihydrogen orthophosphate) to aquatic invertebrates are not available. The assessment was therefore based on experimental data on barium chloride dihydrate. The read across approach is in accordance with Regulation (EC) No. 1907/2006, Annex XI, 1.5.. The acute toxicity of barium sulphate to aquatic invertebrates was tested with wild caught specimen of Daphnia magna (Khangarot and Ray, 1988). The animals were exposed to the substance for 48 hours in a static test system. After 48 hours a LC50 of 32 mg/L based on the element Barium was determined. A comparable test was conducted by Biesinger and Christensen (1972). Daphnia magna were exposed to Barium chloride dehydrate for 48 hours in a static test system. Based on Barium a LC50 of 14.5 mg/L was determined.