Barium hydroxide

Toxicity to other above-ground organisms

Administrative data

Endpoint:

toxicity to other above-ground organisms

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: No guideline study, but study was conducted in a scientifically correct way, and data are useful for the evaluation of Ba-toxicity via oral exposure

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1994

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Original report not available: mice and rats were fed barium via drinking water for 13wk and 2y.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

barium(2+) dichloride dihydrate

EC Number:

600-412-6

Cas Number:

10326-27-9

IUPAC Name:

barium(2+) dichloride dihydrate

Sampling and analysis

Analytical monitoring:

not specified

Details on sampling:

not reported in Dallas and Williams, 2001

Test organisms

Test organisms (species):

other: rats and mice

Details on test organisms:

not reported in Dallas and Williams, 2001

Study design

Study type:

laboratory study

Limit test:

no

Total exposure duration:

104 wk

Test conditions

Test temperature:

not reported in Dallas and Williams, 2001

Details on test conditions:

not reported in Dallas and Williams, 2001

Nominal and measured concentrations:

not reported in Dallas and Williams, 2001

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

13 wk

Dose descriptor:

other: NOAEL

Effect conc.:

2 000 other: ppm barium chloride dihydrate

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

behaviour

Remarks on result:

other: data for rats and mice

Effect concentrations 2

Duration:

104 wk

Dose descriptor:

other: NOAEL

Effect conc.:

60 other: mg/kg/d

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: neoplasms or nonneoplastic lesions

Remarks on result:

other: male rat

Effect concentrations 3

Duration:

104 wk

Dose descriptor:

other: NOAEL

Effect conc.:

75 other: mg/kg/d

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: neoplasms or nonneoplastic lesions

Remarks on result:

other: female rat

Effect concentrations 4

Duration:

104 wk

Dose descriptor:

other: NOAEL

Effect conc.:

75 other: mg/kg/d

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: kidneys, nephropathy, renal tubule regeneration, lymphoid depletions

Remarks on result:

other: male mice

Effect concentrations 5

Duration:

104 wk

Dose descriptor:

other: NOAEL

Effect conc.:

90 other: mg/kg/d

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: kidneys, nephropathy, renal tubule regeneration, lymphoid depletions

Remarks on result:

other: female mice

Details on results:

The main findings of the long-term exposures (13 wk, 2 yr) are summarized hereunder:
- I3 wk study: It was concluded from the neurobehavioural data that there were no consistent effects on behaviour produced by Ba exposure. The No-observed-adverse-effect-level (NOAEL) for this subchronic study was considered to be 2000 ppm Ba chloride dihydrate; this corresponds to 110 mg Ba/kg/d for male rats, 115 mg Ba/kg/d for female rats, 205 mg Ba/kg/d for male mice, and 200 mg Ba/kg/d for female mice. These data were also reported by Dietz et al (1992).
- 13 wk study: Death in mice in the highest dose groups (450 mg Ba/kg/d for males and 495 mg Ba/kg/d for females) were associated with renal toxicity. Renal lesions in rats were much less severe at the highest dose level (200 mg Ba/kg/d for males and 180 mg Ba/kg/d for females).
- In the 2yr study, the evaluated endpoints were hematology values and increases in neoplasms; the conclusion was “no increased incidences of neoplasms or nonneoplastic lesions that could be attributed to BaCl2 dihydrate” for rats receiving average dose rates of 60 (male) and 75 (female) mg/kg/d.
- For mice (endpoints were kidneys, nephropathy, renal tubule regeneration, lymphoid depletions) the identified NOAEL was 75 mg Ba/kg/d for males, and 90 mg Ba/kg/d for females.

Applicant's summary and conclusion

Conclusions:

Data can be used in a weight of evidence approach for the derivation of a PNECoral (secondary poisoning)