Dihydro-2,2-dioctyl-6H-1,3,2-oxathiastannin-6-one

Endpoint summary

Description of key information

Oral

Under the conditions of a OECD 401 and EU Method B.1 guideline study, the oral LD50 value for Dioctyltin mercaptopropionate in Sprague-Dawley rats was established to exceed 2000 mg/kg body weight.

Dermal

By read-across to Dioctyltin oxide, the dermal LD50 of Dioctyltin mercaptopropionate, corrected for molecular weight, is considered to be greater than 2488 mg/kg bodyweight.

Dermal: Read-across to structurally similar substance: DOTO (Dioctyltin oxide)

The acute dermal median lethal dose (LD₅₀) of DOTO determined in a OECD 402 and EU Method B.1 guideline study

in the Wistar strain of rat was determined to be greater than 2000 mg/kg bodyweight.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

2 488 mg/kg bw

Additional information

Oral

The acute oral toxicity potential of Dioctyltin mercaptopropionate to the rat was investigated in accordance with the standardised guidelines OECD 401 and EU Method B.1 under GLP conditions using a fixed dose method. The study was awarded a reliability score of 1 in accordance with the criteria set forth by Klimisch et al. (1997).

A single group of 5 male and 5 female Sprague-Dawley strain rats was dosed at a level of 2000 mg/kg of Dioctyltin mercaptopropionate prepared in coconut oil and observed for a period of 14 days. All animals were killed at the end of the observation period and subjected to necropsy examination.

No mortality occurred during the 14 day post-dose observation period. A slight loss of body weight or a reduced body weight gain were observed in the females at the end of the first week of the study. Clinical signs observed included piloerection, a soft faeces production and a swollen abdomen. A hunched posture and hair loss were also noted in the females. In addition, the skin/fur of the ventral region appeared dirty in the majority of the animals. Necropsy examination revealed no abnormalities.

These results indicate that the test material has little toxic effect in the rat following oral administration of a single dose at a level of 2000 mg/kg. The lack of mortality demonstrates the LD50 to be in excess of 2000 mg/kg body weight.

Under the conditions of this study, the oral LD50 value in Sprague-Dawley rats was established to exceed 2000 mg/kg body weight.

Inhalation

In accordance with column 2 of section 8.5.2 of REACH, the acute toxicity by inhalation study with Dioctyltin mercaptopropionate has been omitted as scientifically unjustified on the grounds that inhalation exposure to the substance is unlikely under normal conditions of use. The acute toxicity of the substance has been determined adequately by the oral route.

Dermal: Read-across to structurally similar substance: DOTO (Dioctyltin oxide)

The acute dermal toxicity of the DOTO was investigated in accordance with standardised guidelines OECD 402 and EU Method B.3. During the study, a group of ten animals (five males and five females) was given a single, 24 -hour, semi-occluded dermal application of the test material to intact skin at a dose level of 2000 mg/kg bw. Clinical signs and bodyweight development were monitored during the study. All animals were subjected to gross necropsy. Under the conditions of the study there were no deaths and no signs of systemic toxicity. Animals showed normal weight gains and there were no signs of dermal irritation. Furthermore, no abnormalities were noted at necropsy. The acute dermal median lethal dose (LD₅₀) of the test material in the Wistar strain of rat was therefore determined to be greater than 2000 mg/kg bw.

By read-across to Dioctyltin oxide, the dermal LD50 of Dioctyltin mercaptopropionate, corrected for molecular weight, is considered to be greater than 2488 mg/kg bodyweight.

Justification for classification or non-classification

The oral LD50 of Dioctyltin mercaptopropionate is > 2000 mg/kg bw. By read-across to Dioctyltin oxide, the dermal LD50 of Dioctyltin mercaptopropionate corrected for molecular weight, is considered to be greater than 2488 mg/kg bodyweight.

Target substance and source substances share the identical organotin moiety, and the organotin moiety is generally recognized as the relevant toxophore of organotins. Mercaptopropionic acid, which is as mercaptopropionate the moiety of the target substance which is not covered by the source substance, is not classified for acute toxicity.

In accordance with the criteria for classification as defined in Annex I, Regulation (EC) No 1272/2008, Dioctyltin mercaptopropionate does not require classification with respect to acute toxicity via the oral or dermal route. Dioctyltin mercaptopropionate is not classified for acute inhalative toxicity because of lacking data