Registration Dossier

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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Description of key information


Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (corrosive)

Eye irritation

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (irritating)

Additional information

The aromatic sulphonic acids, as represented by toluene-4-sulphonic acid (CAS No. 104-15-4) and hydroxybenzenesulphonic acid (CAS No. 1333-39-7) are corrosive to the skin and eye.

A GLP guideline skin irritation study with toluene-4-sulphonic acid conducted in 1988 indicated corrosive properties after 4 hours of exposure; and the effects were not reversible after 7 days. 3-minute exposures followed by washing with water resulted in a much less severe effect that was reversible within 72 hours. During the test on sensitisation the primary skin irritation effect of 0.01 -20% solutions of toluene-4-sulphonic acid

monohydrate in 0.9% NaCl solution was studied. The animals was exposed 24 hours to an occlusive application. An irritation effect was only found with 20%

toluene-4-sulphonic acid

, but in a study by Loden et al (1985) with rabbits, without occlusion and after 4 hours, the same concentration in pure water solution caused burns

A 1962, non-guideline eye irritation study with a 65% solution hydroxybenzenesulphonic acid indicated corrosion of the eye even after 5 seconds of exposure. There was no reversibility indicated within 14 days.

Effects on skin irritation/corrosion: corrosive

Effects on eye irritation: corrosive

Justification for classification or non-classification

Based on existing tests the substance is classificated as "Corrosive" following Regulation 1272/2008. Based on existing studies a tested concentration < 20% didn't caused burns or irreversible effect. Therefore a concentration limit of 20% is set, under that the substance can be classified as "Irritant"