Benzenesulfonic acid, mono- and dialkylation products with C16-20 (even numbered, branched and linear) olefins, calcium salts, calcium carbonate, overbased, including distillates (petroleum), hydrotreated, solvent-refined, solvent-dewaxed, or catalytic dewaxed, light or heavy paraffinic C15-C50

Endpoint summary

Description of key information

Two repeat insult patch tests using the Draize procedure have been provided on the substance to be registered. A further two studies performed on the read-across substances sodium 4-icosylbenzenesulfonate and sodium salt of sulfonated C15-C18 n-alpha-olefin have also been provided to support the conclusions drawn for non-classification with regard to skin sensitisation.   

Additional information

Two studies have been provided using the substance to be registered. The first study (Rue, 1991) was performed as an adaption of the Draize patch test in which 45 volunteers were repeatedly exposed to the test material in order to determine its sensitisation potential. Volunteers received nine 0.2 mL induction applications of the test material, applied under a patch. Applications were made to the same site, unless reactions became so strong that a first or second adjacent site was used to complete the induction. Following a 10 - 15 day rest period, the challenge application was applied to an alternative untreated site and the original induction site. Challenge applications were performed using the 25 mm hill top chamber for 24 hours. 48 or 72 hours after each induction application (24 or 48 hours after patch removal) the test site was examined and graded under light (100 watt). Reactions were scored blind by the same scorer according to a numerical and letter grades system. Under the conditions of the test, there was no identifiable evidence of clinical sensitisation observed among the 45 volunteers completing the study.

In the second repeated insult patch test using the substance to be registered (Rue et al., 1991), the test substance was applied undiluted for a 24 h exposure period under an occlusive patch. The duration of 3 weeks for a total of 9 insults showed no indication of irritation for the test substance and this concentration was chosen for challenge. The study was discontinued early for the analogue substance due to the severe irritation response reported. Under the conditions of this study, there was no identifiable evidence of clinical sensitization observed.

In a dermal sensitisation study with the read across substance sodium 4-icosylbenzenesulfonate in mineral oil, 8 men and 45 women were tested using patch testing. Although contact dermatitis was observed in 3/48 of the test subjects, the test material was not a sensitiser.

In a second read across study, the WHO task group on environmental health criteria for linear alykybenzene sulfonates and related compounds has undertaken a review of published data for the assessment of linear alkylbenzene sulfonates. Based upon this review, the substance (sodium salt of sulfonated C15-C18 n-alpha-olefin) class is considered to be not sensitising to humans.

Based on the available human data, for both the substance to be registered and the two read-across substances, the test material can be considered to be not sensitising, supporting the conclusions made on skin sensitisation.