Registration Dossier
Registration Dossier
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EC number: 209-967-5 | CAS number: 599-61-1
Endpoint summary
Administrative data
Key value for chemical safety assessment
Additional information
The evidence is based on data from the isomer dapsone (4,4'-DDS) Based on the available in-vivo Mouse micronucleus test (bone-marrow), it can be concluded that Dapsone is not mutagenic in-vivo.
This is also confirmed by other in-vitro studies run on Salmonella TA98, TA100, TA 1835, TA 1537 and E. Coli strains WP2 UVRA, WP2 pKM 101 and WP2 uvrA pKM 101, there was no mutagenic effect either with or without activating metabolic system. Under mammalian gene mutation test on tk-locus of L5178 Y mouse lymphoma cells, 4,4 -DDS is not mutagenic in mammalian cells.
Nevertheless, under a chromosome aberration study with 4,4’-DDS performed according to OECD 473 guideline and GLP principles, in cultured peripheral human lymphocytes in two independent experiments, it is concluded that 4,4’-DDS is clastogenic after 3 hours treatment in the absence of S9-mix in human lymphocytes.
Justification for selection of genetic toxicity endpoint
The evidence is based on data from the isomer dapsone (4,4'-DDS) Based on the available in-vivo Mouse micronucleus test (bone-marrow), it can be concluded that Dapsone is not mutagenic in-vivo.
Endpoint Conclusion: No adverse effect observed (negative)
Justification for classification or non-classification
The decision for non-classification is based on a weight of evidence approach. 3,3 -DDS does not contain a structural alert for mutagencity and most experimental studies performed with the isomer 4,4'-DDS (dapsone) in vitro are negative. In vivo studies on clastogenic effects (e.g. micronucleus test) performed with dapsone are also negative.
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