Registration Dossier
Registration Dossier
Data platform availability banner - registered substances factsheets
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Diss Factsheets
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 241-234-5 | CAS number: 17194-00-2
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data
Endpoint summary
Administrative data
Description of key information
Key value for chemical safety assessment
Repeated dose toxicity: via oral route - systemic effects
Endpoint conclusion
- Dose descriptor:
- NOAEL
- 114 mg/kg bw/day
- Study duration:
- subchronic
- Species:
- rat
Repeated dose toxicity: inhalation - systemic effects
Endpoint conclusion
- Endpoint conclusion:
- no study available
Repeated dose toxicity: inhalation - local effects
Endpoint conclusion
- Endpoint conclusion:
- no study available
Repeated dose toxicity: dermal - systemic effects
Endpoint conclusion
- Endpoint conclusion:
- no study available
Repeated dose toxicity: dermal - local effects
Endpoint conclusion
- Endpoint conclusion:
- no study available
Additional information
Read-across BaCl2to Ba(OH)2
Repeated dose toxicity, oral
There are no reliable studies for the repeated dose toxicity via the oral route conducted with Ba(OH)2available. However,the toxicity of barium hydroxide and barium chloride may reasonably be considered to be determined by availability of Ba2+cations. As a first surrogate for bioavailability, the water solubility of a test substance may be used. Barium chloride is highly water soluble with ca. 263 g/L at pH ca. 6.5 (and 510.4 g/L at pH 1.5). Also the water solubility of barium hydroxide is high (37.4 g/L at pH > 13). Hence, any read across from barium chloride to barium hydroxide is considered to be justified and will lead to rather equal effect levels.It is noted; although Ba(OH)2 is a strong base (pH 13 for a 10% solution) it will be neutralised within the gastrointestinal tract (pH approx. 1.5 - 2).
Comparing the results of the different oral studies it becomes obvious that the findings of all these studies are not contradictory. The studies conducted by NTP (1994) and Dietz and co-workers (1992) in rats and mice found similar targets of toxicity; although some differences in sensitivity were found. The main adverse effect caused by barium chloride was the nephrotoxicity in rats and mice of both sexes.
The available data in laboratory animals suggest that the toxicity of ingested barium is similar across species. The lowest NOAEL for nephrotoxic effects in rats or mice were identified from the 13-week drinking water study by Dietz et al. (1992) as the NOAEL of61 mg Ba/kg bw/d in male rats and 81 mg/kg bw/d in female ratsand of about 165 mg Ba/kg bw/d in male mice and166 mg Ba/kg bw/d in female mice.
The no-observable-effect concentration of the 13-weeks NTP study (1994) conducted with barium chloride was estimated to be 2000 ppm as based on changes of the final mean body weights, mean body weight gains, mortality, and renal toxicity at 4000 ppm in both species (LOAEL). The dose of 2,000 ppm represents the NOAEL value of this study corresponding to 110 and 115 mg Ba/kg bw/d in male and female rats, respectively, and 205 and 200 mg Ba/kg bw/d in male and female mice, respectively. Thus,the dose of 110 mg Ba/kg bw/d in male ratsand 115 mg Ba/kg bw/d in female ratscan be regarded as relevant NOAEL for chronic barium toxicity in this 13-week study.
Taken the results for male and female rats from both studies (NTP and Dietz et.al) into consideration, an average NOAEL could safely be calculated at 91 mg Ba/kg bw/d, which results in a re-calculated value of 114 mg/kg bw/d for barium hydroxide.
It is explicitly noted that according to the precautionary principle the “worst case value” of 61 mg Ba/kg bw/d (in male rats according to Dietz et al.) is used for the derivation of DNELs. This value refers to approx. 77 mg Ba(OH)2/ kg bw/d.
However, for classification and labelling purposes it appears appropriate to consider all relevant data on repeated dose oral toxicity. As already mentioned above, the results of the NTP study (1994) and the study performed by Dietz et al. (1992) are not contradictory, and in both investigations similar target organs of toxicity were found and no differences in susceptibility of gender was seen. Therefore, it could safely be stated that the calculation of an average value, using the NOAELs for male and female rats coming from the NTP and the Dietz studies, is considered to be a valid approach for the classification and labelling discussion (see below).
Repeated dose toxicity, dermal
According to regulation (EC) 1907/2006 Annex XI (weight of evidence) and Annex VIII column 2 (repeated dose toxicity), testing for sub-chronic dermal toxicity is not considered to be required, for the following reasons:
- Repeated dose toxicity study via dermal route does not need to be performed since the physico-chemical and toxicological properties do not suggest potential for a significant rate of absorption through the skin.
- The substance is classified as corrosive to skin. Due to animal welfare reasons testing is not allowed. A qualitative approach for hazard assessment was chosen.
Repeated dose Toxicity, inhalation
According to the regulation (EC) 1907/2006 testing on long term inhalation toxicity is considered not being scientifically justified. Barium hydroxide is classified as corrosive by worst case. Therefore, the assumption has to be made that the substance is also corrosive to the respiratory tract. Due to animal welfare testing is not foreseen. However, for risk assessment purposes a DNEL for acute inhalation toxicity, local effects is used based on the available IOEL of 0.5 mg Ba2+/m3for soluble barium compounds. A STEL (15 min) was also calculated based on the IOEL (0.5 mg Ba2+/m3). In conclusion, there is no need to initiate testing on long term inhalation toxicity and derogation is considered to be justified.
Repeated dose toxicity: via oral route - systemic effects (target organ) cardiovascular / hematological: lymph nodes; urogenital: kidneys
Justification for classification or non-classification
The results of the NTP study (1994) and the study performed by Dietz et al. (1992) are not contradictory, and in both investigations similar target organs of toxicity were found and no differences in susceptibility of gender was seen. Therefore, it could safely be stated that the calculation of an average value, using the NOAELs for male and female rats coming from the NTP and the Dietz studies, is considered to be a valid approach for the classification and labelling discussion. The results are as follows:
(i) Dietz et al. (1992): NOAEL of 61 mg Ba/kg bw/d in male rats and 81 mg/kg bw/d in female rats
(ii) NTP (1994): NOAEL of 110 mg Ba/kg bw/d in male rats and 115 mg Ba/kg bw/d in female rats
No classification and labelling of barium hydroxide according to regulation (EC) 1272/2008 as specific target organ toxicant (STOT) – repeated exposure, oral is necessary, since the guidance value for a Category 1 classification of C<10 mg Ba(OH)2/kg bw/day, and the guidance value for a Category 2 classification of 10 <C <100 mg Ba(OH)2/kg bw/day are not met. Based on a “weight of evidence” approach the mean NOAEL for sub-chronic toxicity is 114 mg Ba(OH)2/kg bw/d.
Furthermore, no classification and labelling according to regulation (EC) 1272/2008 are expected for long term oral, dermal and inhalation are expected
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.