Registration Dossier

Administrative data

Description of key information

No primary skin irritation studies were located for RAEs; however, a read-across skin irritation study (similar to OECD 404) from distillate aromatic extract was identified. Although valid in its methodology, the skin irritation assay differs from the current OECD guidelines in that animals were exposed under occluded conditions for 24 hours instead of semi-occluded conditions for 4 hours.  Considering the conditions of the test, results must be interpreted carefully for the purposes of classification and labelling.  The mean scores for erythema and oedema have been assessed against the deviations, and provided the test would be conducted under standard conditions, slight irritation might be expected but insufficient to classify.  Additionally, RAEs did not elicit skin irritation based on observations made during repeated dermal exposure studies. Consequently, RAEs are not expected to be more irritant than DAE based on higher viscosities. Hence, RAEs do not require classification for skin irritation.

For eye irritation, a read-across study from untreated DAE was found to be not irritating in the eyes of rabbits in an eye irritation study (OECD 405).  Therefore, it is unlikely that RAEs are eye irritants.

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)

Additional information

For purposes of classification and labelling and registration under REACH, aromatic extracts are sub-divided into the categories of distillate aromatic extracts (DAE), treated distillate aromatic extracts (TDAE), and residual aromatic extracts (RAE). Distillate aromatic extracts are derived from the extraction conducted on distillate base oils, whereas residual aromatic extracts are the result of extraction on residual oil that has undergone de-asphalation. The starting materials from which DAE and TDAEs are derived boil across the distillation range of 3-7 ring PACs, the constituents of concern that may cause toxicity. In addition, they have a much lower viscosity compared to the residual aromatic extracts. Therefore reading across to data on DAEs for RAEs is likely to be conservative

No primary skin irritation studies were located for RAEs; however, a read-across study from DAEs was identified. In this study, white rabbits (6 male) were dermally exposed to 0.5 mL of light paraffinic distillate solvent extract for 24 hours to both an intact skin site and abraded skin site (API, 1986). Animals then were observed for 14 days. Irritation was scored by the method of Draize (1959). The mean (24 and 72 hour, intact skin) erythema and oedema scores were 2.45 and 2.5, respectively.

Although this test is valid in its methodology, it differs from the current OECD guidelines in that animals were exposed under occluded conditions for 24 hours instead of semi-occluded conditions for 4 hours. Considering the conditions of the test, results must be interpreted carefully for the purposes of classification and labelling. The mean scores for erythema and oedema have been assessed against the deviations, and provided the test would be conducted under standard conditions, slight irritation might be expected but insufficient to classify.

Using this information in conjunction with the results from dermal repeated dose toxicity studies in which RAEs did not elicit skin irritation, RAEs are not expected to be more irritant than DAE based on higher viscosities. Hence, RAEs do not require classification for skin irritation.

One key read-across eye irritation study was identified (API, 1986). In this study, 0.1 mL of undiluted light paraffinic distillate solvent extract was instilled into the conjunctival sac of one eye of 9 white rabbits. Group I animal eyes remained unwashed, while Group II animal eyes were flushed with water for 1 minute, 20 to 30 seconds after instillation. Animals then were observed for 7 days. Irritation was scored by the method of Draize (1959).

 

The mean cornea, iris, conjuctivae scores (24 to 72 hours) were 0.0, 0.0, and 0.44, respectively. In this study, light paraffinic distillate solvent extract is not an eye irritant. DAEs are classified as not irritating to the eye according to EU criteria.

Justification for classification or non-classification

RAEs did not elicit skin irritation based on observations made during repeated dermal exposure studies. RAEs are not expected to be more irritant than DAE based on higher viscosities. Hence, RAEs do not require classification for skin irritation under the CLP Regulation, (EC)1272/2008. Based on read-across information from DAEs, RAEs do not meet the criteria for classification an as eye irritant as defined by the CLP Regulation, (EC)1272/2008.