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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

Toxicological information

Carcinogenicity

Currently viewing:

Administrative data

Description of key information

According to the NTP study performed 1994, the concentration of 2500 ppm represents a NOAEL for carcinogenicity (corresponding to Ba doses of 60 and 75 mg/kg bw/d to male and female rats, respectively, and 160 and 200 mg/kg bw/d to male and female mice, respectively). Based on this value the NOAEL for BaSO4 is calculated at 102 mg/kg bw/day.

Key value for chemical safety assessment

Justification for classification or non-classification

There was no evidence of carcinogenic activity (showing no chemical related increase of malignant or benign neoplasms) of barium chloride in both sexes of rats and mice that received 500, 1250, and 2500 ppm. Thus, the concentration of 2500 ppm represents a NOAEL (corresponding to barium doses of 60 and 75 mg/kg bw/d to male and female rats, respectively, and 160 and 200 mg/kg bw/d to male and female mice, respectively). No classification of the substance as CMR substance is required.

Additional information

Read across barium chloride to barium sulfate:

The toxicity of barium sulfate 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. 375 g/L at pH ca. 6.5 (pH of artificial sweat solution), whereas barium sulfate is poorly soluble (3.1 mg/L at pH 9). Hence, any read across from barium chloride to barium sulfate is inherently very conservative.

 

Carcinogenicity, oral:

In a 2-year carcinogenicity study (NTP, 1994) groups of 60 male and 60 female F334/N rats received barium chloride dihydrate in drinking water at concentrations of 0, 500, 1250, and 2500 ppm (corresponding to the average daily dose of 0, 15, 30, and 60 mg Ba/kg bw to males and 0, 15, 45, and 75 mg Ba/kg bw to females). In the same study groups of 60 male and 60 female B6C3F1 mice received BaCl2·2H2O in drinking water at concentrations of 0, 500, 1250, and 2500 ppm (corresponding to the average daily dose of 0, 30, 75, and 160 mg Ba/kg bw to males and 0, 40, 90, and 200 mg Ba/kg bw to females).

In rats, there was no treatment-related effect on survival. At the end of 2 years, there were no increased incidences of neoplasms or nonneoplastic lesions in rats that could be related to the test substance. However, there was dose-related decreased incidence of adrenal medulla pheochromocytoma and mononuclear cell leukemia in male rats. In mice, survival and final mean body weights of male and female mice receiving 2500 ppm were significantly lower than those of controls. No increased incidence of neoplasms was observed in exposed mice. The incidence of nephropathy and lymphoid depletion were significantly increased in male and female groups receiving 2500 ppm. In addition, the relative and absolute spleen weights were lower in these groups than in controls.

In conclusion, there was no evidence of carcinogenic activity (showing no chemical related increase of malignant or benign neoplasms) of barium chloride in both sexes of rats and mice that received 500, 1250, and 2500 ppm. Thus, the concentration of 2500 ppm represents a NOAEL (corresponding to barium doses of 60 and 75 mg/kg bw/d to male and female rats, respectively, and 160 and 200 mg/kg bw/d to male and female mice, respectively).

 

Carcinogenicity, dermal:

It can be stated that the systemic availability of barium sulfate following dermal exposure is approx 1% (following HERAG fact sheet - assessment of occupational dermal exposure and dermal absorption for metals and inorganic metal compounds; EBRC Consulting GmbH / Hannover /Germany; August 2007). No adverse health effects were observed in 90-day repeated dose oral toxicity studies at the limit dose, indicating an absence of systemic toxicity. Furthermore, barium sulfate is void of genetic toxicity. Therefore, the conduct of a carcinogenicity study via the dermal route is considered dispensable.

 

Carcinogenicity, inhalation:

Exposure of barium sulfate via inhalation leads only to Baritosis in humans which were exposed to significant concentrations. Baritosis does not produce any symptoms, abnormal physical signs, incapacity for work, interference with lung function, nor liability to develop pulmonary of bronchial infection or other thoracic disease. Therefore, and in accordance with regulation (EC) 1907/2006 Annex X column 2 no testing proposal for a carcinogenicity study is included into the registration dossier of barium sulfate. The substance is neither classified as mutagen category 1 -3 nor there is evidence from the repeated dose studies that the substance is able to induce hyperplasia and / or preneoplastic lesions.