Boron trichloride

Genetic toxicity: in vivo

Administrative data

Endpoint:

genetic toxicity in vivo

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: A degradation category approach is applied, based on the very rapid hydrolysis of boron trichloride. The description and justification of the category is presented in Section 13.

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Data source

Reference

Reference Type:

other: REACH registration dossier

Title:

Unnamed

Year:

2010

Materials and methods

Test material

Test material information

Constituent 1

Reference substance name:

Hydrogen chloride

EC Number:

231-595-7

EC Name:

Hydrogen chloride

Cas Number:

7647-01-0

IUPAC Name:

chloride

Constituent 2

Reference substance name:

boric acid

IUPAC Name:

boric acid

Results and discussion

Any other information on results incl. tables

In the in vivo situation, BCl3 contacts first a mucous membrane most likely in the upper airways and then is transported by blood to the target organs such as bone marrow. HCl and also boric acid are released when BCl3 is coming into contact with the water. Both degradation products are well investigated and were reported to be not genotoxic, neither in vitro nor in vivo. False positive results were only reported in case of significantly lowering of the pH by HCl in in vitro studies.

Relevant information for the 2 degradation products:

Hydrogen chloride:

According to column 2 of Annex IX of REACH, in vivo genotoxicity assays will be required if a positive result is seen in in vitro genotoxicity assays. Hydrochloric acid is not genotoxic in in vitro tests using bacterial or simple eukaryotic cells, while its effects on the pH of the medium precludes the possibility of testing in other in vitro non-bacterial systems. Hydrochloric acid rapidly dissociates almost completely in contact with water, releasing the chloride ion and the hydrogen ion which combines with water to form the hydronium ion. Both chlorine and hydronium ions are normally present in the body, and mammals constantly secrete gastric juices, containing hydrogen ion concentrations equivalent to 0.17 N HCl, into the stomach.

 

Boric acid:

In vitro gene mutation studies in bacteria and in mammalian cells, and in vitro cytogenicity studies concluded that boric acid is not genotoxic under the conditions of the studies. In addition, the results of an in vivo bone marrow cytogenetic assay (chromosome aberration) also showed boric acid to be non genotoxic.

Endpoint conclusion:

There are no indications from the degradation products that BCl3 could be mutagenic/genotoxic.

 

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): negative
There are no indications from the degradation products that BCl3 could be mutagenic/genotoxic.

Executive summary:

In the in vivo situation, BCl3 contacts first a mucous membrane most likely in the upper airways and then is transported by blood to the target organs such as bone marrow. HCl and also boric acid are released when BCl3 is coming into contact with the water. Both degradation products are well investigated and were reported to be not genotoxic, neither in vitro nor in vivo. False positive results were only reported in case of significantly lowering of the pH by HCl in in vitro studies.

Relevant information for the 2 degradation products:

Hydrogen chloride:

According to column 2 of Annex IX of REACH, in vivo genotoxicity assays will be required if a positive result is seen in in vitro genotoxicity assays. Hydrochloric acid is not genotoxic in in vitro tests using bacterial or simple eukaryotic cells, while its effects on the pH of the medium precludes the possibility of testing in other in vitro non-bacterial systems. Hydrochloric acid rapidly dissociates almost completely in contact with water, releasing the chloride ion and the hydrogen ion which combines with water to form the hydronium ion. Both chlorine and hydronium ions are normally present in the body, and mammals constantly secrete gastric juices, containing hydrogen ion concentrations equivalent to 0.17 N HCl, into the stomach.

 

Boric acid:

In vitro gene mutation studies in bacteria and in mammalian cells, and in vitro cytogenicity studies concluded that boric acid is not genotoxic under the conditions of the studies. In addition, the results of an in vivo bone marrow cytogenetic assay (chromosome aberration) also showed boric acid to be non genotoxic.

Endpoint conclusion:

There are no indications from the degradation products that BCl3 could be mutagenic/genotoxic.