Dodecane-1-thiol

Endpoint summary

Description of key information

Key data were identified to evaluate the acute oral and acute dermal toxicity potential of dodecane-1-thiol. Key read across data from octane-1-thiol and 1,1-dimethylheptanethiol (strucural analogs of dodecane-1-thiol) were available to evaluate the acute inhalation toxicity potential. The key acute paramaters are presented below:
• Acute oral LD50: >5000 mg/kg bw
• Acute Inhalation LC50: >7.04 mg/L (based on 1,1-dimethylheptanethiol)
• Acute Dermal LD50: >2000 mg/kg bw
 

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Dose descriptor:

LD50

Value:

5 000 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Dose descriptor:

LC50

Value:

7.04 mg/m³ air

Acute toxicity: via dermal route

Endpoint conclusion

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Additional information

Acute Oral Toxicity

 

One key study was identified to evaluate the acute oral toxicity potential of dodecane-1-thiol.

In a key acute toxicity study (Latven 1977; Klimisch score = 2), male WBS/W rats (10/dose) were orally administered (via gavage) a single dose of dodecane-1-thiol at 5000 mg/kg bw. The animals were subsequently observed for a period of 14 days. No mortalities were observed through the study period. Significant daily body weight losses were observed in all test animals for the first three to four days post-treatment. However, all animals exhibited complete recovery by days six to eleven post-treatment. Based on the lack of mortality and treatment-related adverse systemic effects, the acute oral LD₅₀ for dodecane-1-thiol was determined to be >5000 mg/kg bw.

Acute Inhalation Toxicity

 

No key studies were identified for dodecane-1-thiol. Two key read across acute inhalation toxicity studies that evaluated octane-1-thiol and 1,1-dimethylheptanethiol were identified.

In a key read across acute inhalation toxicity study (Collins, 1986; Klimisch score = 2), young adult Sprague-Dawley rats (5/sex) were exposed (head only), to 3.10 mg/L octane-1-thiol for 4.5 hours. Animals were subsequently observed for a period of 14 days.  No mortality was observed and no treatment-related macroscopic or microscopic changes were evident through the study period. Clinical signs such as ataxia, lethargy, salivation, lachrymation, and piloerection were observed immediately following exposure but disappeared by day 2 post-exposure. Gross necroscopy did not reveal any remarkable findings. Based on the lack of adverse systemic effects observed, the inhalation LC₅₀ for octane-1-thiol was determined to be >3.10 mg/L.

 

In another key read across acute inhalation toxicity study (Collins, 1987; Klimisch score = 1), groups of Crl:CD(SD)BR strain rats (5/sex) were exposed via the inhalation route to 1,1-dimethylheptanethiol for 4 hours at a concentration of 7.04 mg/L. Animals were subsequently observed for a period of 14 days. No mortality was observed in either male or female mice through the study period. Clinical signs such as ataxia, piloerection, wet fur, and transient salivation were observed in treated animals. There were no treatment-related effects on body weight and gross necropsy did not reveal any remarkable findings. Based on the lack of mortality and adverse systemic toxicity effects, the acute inhalation LC₅₀ for 1,1-dimethylheptanethiol was determined to be >7.04 mg/L.

Acute Dermal Toxicity

 

One key study was identified to evaluate the acute dermal toxicity potential of dodecane-1-thiol.

 

In an acute dermal toxicity study (Latven, 1977; Klimisch score = 2), six male albino rats were dermally exposed to dodecane-1-thiol at a dose of 2000 mg/kg bw. Animals were subsequently observed for a period of 7 days. All animals remained asymptomatic and gained body weight during the observation period. The acute dermal LD₅₀ for dodecane-1-thiol was therefore determined to be >2000 mg/kg bw.

Justification for classification or non-classification

Based on evaluation of the acute oral, inhalation, and dermal toxicity data discussed above, dodecane-1-thiol does not meet the criteria for classification as an acute oral, inhalation, or dermal toxicant under EU Dangerous Substances Directive 67/548/EEC or CLP EU Regulation 1272/2008 because the LD(C)₅₀ values reported for this substance exceed the upper discriminating threshold limits for classification defined in the regulations.