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

Endpoint summary

Description of key information

Skin Irritation

Under the conditions of a study according to OECD guideline 439 and EU Method B.46, Dioctyltin mercaptopropionate is non-irritant in the in vitro skin irritation test.

Skin Corrosion

Under the conditions of a study according to OECD guideline 431 and EU Method B.40 BIS, Dioctyltin mercaptopropionate is not corrosive in the in vitro skin corrosion test.

Eye Irritation

Under the conditions of a study according to OECD guideline 437 and EU Method B.47, Dioctyltin mercaptopropionate induced an IVIS ≤ 3, no classification is required for eye irritation or serious eye damage.

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

Skin Irritation

An in vitro skin irritation test using a human skin model was carried out in accordance with the standardised guidelines OECD 439 and EU Method B.46 under GLP conditions. The study was awarded a reliability score of 1 in accordance with the criteria set forth by Klimisch et al. (1997).

Triplicate tissues were treated with the test material for an exposure period of 15 minutes. At the end of the exposure period each tissue was rinsed before incubating for 42 hours. Dioctyltin mercaptopropionate was found to directly reduce MTT and therefore additional non-viable tissues were incorporated into the testing for correction purposes. At the end of the post exposure incubation period each tissue was taken for MTT-loading. The maintenance medium from beneath each tissue was transferred to pre-labelled micro tubes and stored in a freezer for possible inflammatory mediator determination. After MTT-loading a total biopsy of each epidermis was made and placed into micro tubes containing acidified isopropanol for extraction of formazan crystals out of the MTT loaded tissues. 

At the end of the formazan extraction period each tube was mixed thoroughly and duplicate 200 µL samples were transferred to the appropriate wells of a pre-labelled 96 well plate. The optical density was measured at 570 nm.

The relative mean viability of the test material treated tissues was 93.1% after the 15 minute exposure period and 42 hours post exposure incubation period. The quality criteria required for acceptance of results in the test were satisfied.

Under the conditions of this study, Dioctyltin mercaptopropionate is non-irritant in the in vitro skin irritation test.

Skin Corrosion

An in vitro skin corrosion test was performed with Dioctyltin mercaptopropionate using a human skin model in accordance with the standardised guidelines OECD 431 and EU Method B.40 BIS under GLP conditions. The study was awarded a reliability score of 1 in accordance with the criteria set forth by Klimisch et al. (1997).

The corrosivity potential of Dioctyltin mercaptopropionate was evaluated using the EpiDerm™ Human Skin Model after treatment periods of 3 and 60 minutes. Duplicate tissues were treated with the test material for exposure periods of 3 and 60 minutes. Negative and positive control groups were treated for each exposure period.  Dioctyltin mercaptopropionate was found to directly reduce MTT and therefore additional non-viable tissues were incorporated into the testing for correction purposes. At the end of the exposure period the Dioctyltin mercaptopropionate was rinsed from each tissue before each tissue was taken for MTT loading. After MTT loading each tissue was placed in 2 mL isopropanol for MTT extraction.

At the end of the formazan extraction period each well was mixed thoroughly and triplicate 200 µL samples were transferred to the appropriate wells of a pre-labelled 96 well plate. The optical density (OD) was measured at 570 nm (OD570).

The percentage viability of the Dioctyltin mercaptopropionate treated tissues after exposures of 3 and 60 minutes was 78.2 and 101.5 %, respectively. The quality criteria required for acceptance of results in the test were satisfied.

Under the conditions of this study, Dioctyltin mercaptopropionate is not corrosive in the in vitro skin corrosion test.

Eye Irritation

The eye irritation potential of Dioctyltin mercaptopropionate was evaluated in vitro in accordance with the standardised guidelines OECD 437 and EU Method B.47, under GLP conditions using the Bovine Corneal Opacity and Permeability test (BCOP test). The study was awarded a reliability score of 1 in accordance with the criteria set forth by Klimisch et al. (1997).

The eye damage of Dioctyltin mercaptopropionate was tested in isolated bovine corneas through topical application for 240 minutes. Dioctyltin mercaptopropionate was applied undiluted and concurrent negative and positive controls were run using sodium chloride 0.9 % (w/v) and 20 % w/v imidazole solution in sodium chloride 0.9 % (w/v), respectively. The two endpoints, decreased light transmission through the cornea (opacity) and increased passage of sodium fluorescein dye through the cornea (permeability) were combined in an empirically derived formula to generate an In Vitro Irritancy Score (IVIS). 

Dioctyltin mercaptopropionate had a mean IVIS of 0.2 after 240 minutes of treatment.

The positive control IVIS was within the range of 65.1 to 123.3. The positive control acceptance criterion was therefore satisfied. The negative control gave opacity of ≤ 2.4 and permeability ≤ 0.072. The negative control acceptance criteria were therefore satisfied.

Under the conditions of this study, as Dioctyltin mercaptopropionate induced an IVIS ≤ 3, no classification is required for eye irritation or serious eye damage.

Justification for classification or non-classification

Dioctyltin mercaptopropionate did not show a skin irritation/skin corrosion or eye irritation/eye corrosion potential in reliable in vitro tests.

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 skin and eye corrosion or irritation.