Tin disulphide

Endpoint summary

Description of key information

Both in vitro and in vivo studies were performed in a tiered testing approach, demonstrating that Tin disulfide

is not corrosive or irritating to skin and eye. The same approach was done for read-across substance

Tin sulfide, which also was negative for skin and eye corrosion and irritation.

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

In vitro studies to predict skin corrosion and irritation of tin disulfide were performed by means of MatTek EpiDerm(TM) according to OECD 431 (Piehl, 2012a) and OECD 439 method (Piehl, 2012b). In the first study, mean tissue viability was 99.4% (3 min) and 96.7% (60 min); predicted corrosivity of tin disulfide was non-corrosive. In the second study, mean tissue viability was 101.2%, therefore predicted irritation potential was non-irritant. These studies, with negative outcome, were not enough for classification, therefore they were considered to be supportive. As a final step, a key in vivo study for skin irritation was performed in New Zealand White rabbits with tin disulfide by semi-occlusive dermal application according to OECD 404 method (Yasso, 2012). Erythema and edema were scored at 1, 24, 48 and 72 hours and on Day 7 following patch removal. At 1 hour post exposure, erythema was absent to very slight and edema was absent. At 24 hours erythema was very slight, edema was absent and shiny areas were observed in one animal. By 48 hours, erythema was absent to very slight and edema was absent with shiny areas and flaking skin observed. Erythema remained absent to very slight, edema was absent and flaking skin persisted at 72 hours. Both erythema and edema were absent by Day 7. No abnormal physical signs were observed.Two animals had net body weight gain by study termination, although one of the animals lost weight between 72 hours and Day 7. The remaining animal lost weight by study termination. The Modified Primary Irritation Index was 0.55. In conclusion, tin disulfide is not a Category 2 irritant according to CLP Regulation. Supporting information was also available from tin sulfide as read across substance. MatTek EpiDerm(TM) testing according to OECD 431 showed a mean tissue viability of 101.3% (3 min.) and 107.8% (60 min.), therefore predicted corrosivity of tin sulfide was non-corrosive (Piehl, 2010a). Dermal irritation potential tested in MatTek Epiderm(TM) according to OECD 439 showed a mean tissue viability of 101.5%, therefore predicted irritation potential of tin sulfide was non-irritant (Piehl, 2010b). Finally, in vivo testing for skin irritation in rabbits according to OECD method 404 demonstrated that there was no erythema or edema observed after 4 hours semi-occlusive application. Test article stained the dose sites at all observation periods, but there were no abnormal physical signs and body weights were normal. Tin disulfide and Tin sulfide showed a comparable tolerance profile for this endpoint.

 

An in vitro study to predict eye damage and irritation of tin disulfide was performed by means of HETCAM test according to Invittox method No. 47 (Cerven, 2012). The chorioallantoic membrane (CAM) of White Leghorn eggs, incubated for 10 days, was dosed with 0.3 mL test substance at 10% (w/v) in olive oil, leading to an irritation score (IS) of 0. Based on a threshold concentration of >10% and the IS 10% of 0, the irritating potential of the test article, was determined as none to slight. This study, with negative outcome, was not enough for classification, therefore it was considered to be supportive. Next, a key in vivo study according to Draize method was performed with tin disulfide in three New Zealand White rabbits (Blair, 2012). The test article (0.1 mL equivalent (94.4 mg)) was placed into the conjunctival sac of one eye of each rabbit. The eyes were examined pretest and scored by the Draize technique at 1, 24, 48 and 72 hours postdose. There was no corneal opacity or iritis noted at any observation period. Conjunctival irritation of redness and or discharge, was noted in two out of three eyes, one eye cleared by 24 hours and the other eye by 48 hours. The control eyes appeared normal at all observation periods. There were no abnormal physical signs noted during the observation period. One animal gained body weight and the other two animals remained the same. Supporting information was also available from tin sulfide as read across substance. HETCAM testing according to Invittox showed an irritation score of 0 (Cerven, 2010), whereas in vivo testing for eye irritation in rabbits according to OECD method 405 demonstrated that there was no eye irritation (Blair, 2010). Tin disulfide and Tin sulfide showed a comparable tolerance profile for this endpoint.

 

Justification for selection of skin irritation / corrosion endpoint:
Key in vivo study with reference substance confirming absence of irritation 

Justification for selection of eye irritation endpoint:
Key in vivo study with reference substance confirming absence of irritation

Justification for classification or non-classification

No classification and labelling is needed for skin and eye corrosion or irritation of tin disulfide according to EU labelling regulations Commission Directive 93/21/EEC and CLP regulation (No. 1272/2008 of 16 December 2008).