Registration Dossier

Administrative data

Key value for chemical safety assessment

Additional information

In vitro gene mutation study in bacteria

Both the key and supporting AMES studies showed no reverse mutation with or without S9 activation.

Cytogenicity study in mammalian cells/micronucleus study

The in vivo micronucleus test showed no evidence of genetic toxicity. However, the results from the non-disjunction assay produced a positive result without metabolic activation. This shows the potential for dioctylin dichloride to induce chromasonal aberrations.

Gene mutation study in mammalian cells

No genetic toxicity was observed in the in vivo mouse lymphoma study. With respect to the in vitro studies, both of the HGPRT tests produced negative results, as did the test on chinese hamster cells. But a positive result without activation was seen in the in vitro mouse lymphoma assay.

DNA damage and repair studies

Both of the in vivo DNA damage and repair studies produced negative results. The in vitro DNA repair examinations of both human fibroblasts and rat hepatocytes, did not show evidence of substance related effects. The supporting study looking at covalent DNA binding also produced a negative result.


Short description of key information:
The below information details the results of the in vitro studies
Genetic toxicity in vitro AMES.Key Study 001. Negative with and without activation.
Genetic toxicity in vitro AMES. Support Study 001. Negative with and without activation
Genetic toxicity in vitro. DNA repair test (human fibroblasts). Negative
Genetic toxicity in vitro. DNA repair test (rat hepatocytes). Negative
Genetic toxicity in vitro. Gene mutation HGPRT test. Negative with and without activation
Genetic toxicity in vitro. Mouse Lymphoma. Positive without activation, negative with activation
Genetic toxicity in vitro. Chinese hamster cells. Negative without activation
Genetic toxicity in vitro. Lack of Covalent DNA binding. Negative with and without activation for Calf Thymus DNA. Negative for Chinese hamster lung fibroblasts (V79)
Genetic toxicity in vitro. Non-disjunction. Positive without activation, negative with activation.
Genetic toxicity in vitro.HGPRT test G 89/1. Negative with and without activation

The below information details the results of the in vivo studies
Genetic toxicity in vivo. Mouse Lymphoma. Negative
Genetic toxicity in vivo. Sister Chromatic Exchange, Bone Marrow. Negative
Genetic toxicity in vivo. Rat Liver and Thymus DNA. Negative
Genetic toxicity in vivo. Micronucleus test in bone marrow cells. Negative

All studies flagged as key studies were rated at least reliability score 2 according to the criteria of Klimisch et al, 1997, based upon depth of reporting and methodologies inline with generally accepted scientific principles.

As the genetic toxicity endpoint has been investigated thoroughly and in different ways the information presented is considered to represent a complete picture of genetic toxicity potential.

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Two positive results were seen in in vitro genetic toxicity studies. The positive result in the non-disjunction assay will not lead to a classification with respect to cytogenicity as no positive effects were seen in the in vivo micronucleus study. The positive result in the in vitro mouse lymphoma assay will not lead to classification with respect to gene mutation as the in vivo equivalent showed no evidence of genetic mutation.

In conclusion, the evidence from the available studies suggests that dioctyltin dichloride does not display genetic toxicity, and as such does not require any classification in this field.