4-tert-butylbenzaldehyde

Endpoint summary

Description of key information

Skin:
In vivo:
- Rabbit, 24 h, occlusive, 3 animals tested (Draize test): not irritating; erythema and edema scoring <1.5 in all animals (24, 48, 72 h), remaining desquamation after 8 days (BASF79/168-a)
Eye:
In vivo
- Rabbit, 24 h, substance was not washed out (Draize test): not irritating (BASF AG 1981, Val. 2)
- Rabbit, 24 h, substance was not washed out (Draize test): not irritating (TSCATS 1979, Val. 2)
Respiratory system:
No information is available.

Additional information

There are valid in vivo data available for the assessment of the skin and eye irritation potential of p-tert-butylbenzaldehyde.

 

Skin:

In the key study for skin irritation, p-tert-butylbenzaldehyde was investigated in a Draize test for its skin irritation potential. 0.5 ml of the undiluted substance was applied for 24 hours on the clipped skin of 3 Vienna White rabbits under occlusive conditions (BASF79/168-a). Both erythema as well as edema scoring was <1.5 in all three animals, regarding the reading time points at 24, 48 and 72 h. At the end of the observation period after 8 days, slight desquamation was found in 3/3 animals.

In a supportive Draize test, the undiluted substance was applied for 3 min and 2 hours on the skin of 2 Vienna White rabbits under occlusive conditions (BASF79/168-b). Also in this experiment the substance produced questionable erythema/edema with mean scores of </= 1 in each animal, including the reading time points at 24, 48 and 72 h. Desquamation was seen at the end of the observation period on day 8 in one animal and questionable erythema was still existent in both animals after a 2 hours occlusive application of p-tert-butylbenzaldehyde.

Taken together, slight and reversible irritating effects were seen on the skin of the animals (mean scores were < 1.5 at all relevant reading time points) and remaining desquamation was observed after 8 days and slight erythema in one animal. These findings became evident after harsh testing conditions in the chosen key study compared to actual guideline recommendations (24 hour occlusive application). Therefore, the substance is judged not to be a skin irritant, despite of the questionable erythema in the supporting study, which was still existent at the end of the study period on day 8. This conclusion is further supported by an acute dermal toxicity study in rats, in which the slight irritating effects observed were also fully reversible within 7 days (see Chapter 7.2.3).

Eye:

In the key study for eye irritation, p-tert-butylbenzaldehyde was tested in six Vienna White rabbits in a Draize test. Eyes were left unwashed after application of 0.1 ml p-tert-butylbenzaldehyde and the animals were observed for 8 days (BASF79/168). Slight effects (mean scores < 1) were seen on the cornea of 1/6 animals regarding the reading time points at 24, 48 and 72 h.

Slight to evident conjunctival redness was found in 6/6 animals (mean score including all animals and relevant timepoints = 0.94). The effects observed on cornea were fully reversible within 72 h, the scores obtained for conjunctiva redness were fully reversible within 8 days.

Taken together, the slight effects seen for p-tert-butylbenzaldehyde, which were completely reversible at least within 8 days are used as a basis for classifying p-tert-butylbenzaldehyde as non irritant according to EU and GHS criteria.

Justification for classification or non-classification

The present data on skin and eye irritation do not fulfill the criteria laid down in 67/548/EEC and 1272/2008/EEC, and therefore, a non-classification is warranted.