Registration Dossier

Administrative data

Description of key information

The key study for skin irritation, conducted according to a test protocol that is comparable to the appropriate OECD Test Guideline 404, but not in compliance with GLP, found 3-trimethoxysilylpropane-1-thiol not irritating to the skin of New Zealand white rabbits (BRRC 1990).

The key study for eye irritation, conducted according to a test protocol that is comparable to the appropriate OECD Test Guideline 405, but not in compliance with GLP, found 3-trimethoxysilylpropane-1-thiol not irritating to the eyes of New Zealand white rabbits (BRRC 1990).

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

The key study for skin irritation (BRRC 1990) applied the undiluted test material (0.5 ml) to the intact (shaved) skin of six New Zealand white rabbits for four hours under an occlusive dressing. The dressings were then removed, the skin washed and the skin reactions observed for up to 14 days. None of the rabbits had any signs of skin irritation, and no other clinical signs of toxicity were observed. It was therefore concluded by the study authors that the test substance was not irritating to the skin.

Additional skin irritation studies were also available, which did not meet current guideline requirements, but add supporting information for this endpoint and support the conclusion of the key study (DCC, 1969, DCC 1961, Consultox 1976).

The key study for eye irritation (BRRC 1990) instilled the test material into the lower conjunctival sac of one eye per rabbit (six rabbits per volume). The eyelids were held together for one second. The eyes were scored, by a scoring system similar to that recommended in OECD test guideline 405, at one, four and 24 hours, 2, 3 and 7 days after dosing. Additional readings were made, if necessary, at 14 and 21 days. Fluorescein (2%) staining was used to determine corneal injury before dosing and one day after instillation. No corneal injury or iritis was observed in any of the eyes. Within one hour minor transient conjunctival irritation (redness) was observed in 5/6 animals from the 0.1 ml group. All eyes were normal within 48 hours. Therefore, overall the test substance was not irritating to eyes.

Additional eye irritation studies were also available, which did not meet current guideline requirements, but add supporting information for this endpoint and support the conclusion of the key study (DCC, 1969, DCC 1963, Consultox, 1976).


Justification for classification or non-classification

Based on the available data, 3-trimethoxysilylpropane-1-thiol does not require classification for irritation according to Regulation (EC) No. 1272/2008.