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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.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

Administrative data

Key value for chemical safety assessment

Additional information

In Vitro Genetic Toxicity

 

One key study was identified to evaluate the in vitro genotoxic toxicity potential of dodecane-1-thiol in bacteria.

 

In a key bacterial reverse mutation assay (Pence, 1983a; Klimisch score = 1), Salmonella typhimurium strains TA 98, 100, 1535, 1537, and 1538 were exposed to dodecane-1-thiol in DMSO at concentrations of 123.5, 374.4, 1111, 3333, and 10,000 μg/mL in the presence and absence (± S9) of metabolic activation. Exposure to five graded doses of dodecane-1-thiol in the presence and absence of metabolic activation did not result in an increase in the number of revertants. The positive controls did induce the appropriate response. Dodecane-1-thiol is therefore not considered to be mutagenic in the bacterial reverse mutation assay.

 

Supporting data available from a publication (Zeiger et al., 1987; Klimisch score = 2) also indicates that dodecane-1-thiol is not mutagenic when tested in the bacterial reverse mutation assay.

 

One key study was identified to evaluate the in vitro cytogenicity of dodecane-1-thiol in mammalian cells.

 

In a key mammalian sister chromatid exchange assay (Hazleton, 1984; Klimisch score = 1), Chinese hamster ovary cells (K-1, Number CCL61) were exposed to dodecane-1-thiol (CAS Number 112-55-0) at concentrations of 0.1, 0.3, 1.0, 3.3, or 10 µg/mL with and without metabolic activation (S-9 from Aroclor induced rats). Cytotoxicity was observed at the highest dose level tested. No statistically significant increase in the number of SCE’s per chromosome occurred at any dose of the test substance with or without activation. Dodecane-1-thiol was therefore determined to be negative in this study.

 

One key study was identified to evaluate the in vitro gene mutation potential of dodecane-1-thiol in mammalian cells.

 

In a key mammalian cell gene mutation assay, L5178Y mouse lymphoma cells cultured in vitro were exposed to dodecane-1-thiol at concentrations at 1.8, 2.7, 4.0, 6.0, 9.0, 13.5, 20.1, and 30.0 µg/mL in the presence and absence of mammalian metabolic activation. Concurrent positive controls were ethylmethane sulfonate (620 µg/mL) without metabolic activation and 3 -methylcholanthrene (3 µg/mL) with metabolic activation. A negative and solvent control was also employed concurrently. Exposure to eight graded doses of dodecane-1 -thiol, in the presence and absence of metabolic activation, did not increase the induction of forward mutations in L5187Y mouse lymphoma cells at the T/K locus. Dodecane-1-thiol is therefore considered to be negative in the in vitro mammalian cell gene mutation assay.

In Vivo Genetic Toxicity

One key study was identified to evaluate the in vivo genetic toxicity potential of dodecane-1-thiol.

In an in vivo bone marrow micronucleus assay, ICR mice (5/sex/dose) were orally administered (via gavage) dodecane-1-thiol in corn oil at singe doses of 0, 1250, 2500, or 5000 mg/kg bw. Bone marrow cells were harvested at 24, 48, and 72 hours post-treatment and examined microscopically for micronucleated polychromatic erythrocytes.

No mortality occurred in male or female mice in the micronucleus study. Signs of toxicity included lethargy and diarrhea in male and female mice at all dose levels and crusty eyes in one male dosed at 5000 mg/kg bw. Slight reductions (up to 23%) in the ratio of polychromatic erythrocytes to total erythrocytes was observed in some of the test article-treated groups relative to the vehicle control groups. No significant increase in micronucleated polychromatic erythrocytes in test article-treated groups relative to the respective vehicle control group was observed in male or female mice at 24, 48 or 72 hours after dose administration (p>0.05, Kastenbaum-Bowman). n-dodecyl mercaptan did not induce a significant increase in micronucleated polychromatic erythrocytes in either male or female mice. Therefore, dodecane-1-thiol was concluded to be negative in the mouse micronucleus assay.


Short description of key information:
Multiple key studies were identified to evaluate the in vitro and in vivo genetic toxicity potential of dodecane-1-thiol. Dodecane-1-thiol was not mutagenic to Salmonella typhimurium in vitro and was negative in a mammalian sister chromatid exchange assay using Chinese Hamster Ovary (CHO) cells. Dodecane-1-thiol did not increase the induction of forward mutations in L5187Y mouse lymphoma cells at the T/K locus and did not induce an increase in micronucleated polychromatic erythrocytes in an in vivo mouse bone marrow micronucleus assay.

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

All in vitro genetic toxicity studies (i.e., gene mutation studies in bacteria; cytogenicity studies in mammalian cells; and gene mutation studies in mammalian cells) from dodecane-1-thiol showed negative results. An in vivo mouse micronucleus study with dodecane-1-thiol also produced no evidence of genotoxicity. Consequently, dodecane-1-thiol does not meet the criteria for classification and labelling as described in EU Dangerous Substances Directive 67/548/EEC or CLP EU Regulation 1272/2008.