Registration Dossier

Administrative data

Description of key information

Two read-across studies with an exposure period of 4 hours and semi-occlusive exposure conditions were identified from decene trimer hydrogenated (OECD 404) and 1-dodecene dimer with 1 -decene, hydrogenated (OECD 404).  None of the test materials these studies were identified as dermal irritants in rabbits.  
One key eye irritation study (OEC 405) was identified. 1-Decene trimer, hydrogenated and tetramers was not found to be irritating to the eyes of rabbits in this study.

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

Eight key studies were identified which evaluated the dermal irritation potential of poly alpha olefins and their structural analogues. However, only two of the eight strictly adhered to the current OECD 404 guidelines (4 hour exposure, semi-occlusive conditions) with mean scores for erythema and oedema averaged over 24, 48, and 72 hours. These two studies were conducted with decene trimer hydrogenated and 1-dodecene dimer with 1-decene, hydrogenated. The remaining studies, using occlusive methods and/or skin contact times exceeding 4 hours duration, although considered less reliable since the exposure conditions were more stringent than guideline, produced similar results to the semi-occluded studies conducted for 4 hours. Only one of the studies using occlusive methods and an extended exposure time reported mean erythema or oedema scores exceeding the thresholds for classification (dec-1-ene dimers, hydrogenated), the remaining did not. The two studies on decene trimer hydrogenated and 1-dodecene dimer with 1-decene, hydrogenated are discussed in further detail below and are the presented in the table above because they were the only studies used in the evaluation of classification and labeling. An additional two supporting studies specifically on 1-decene trimer, hydrogenated and tetramers also are presented in the table above; however, they are not discussed below because they do not meet current OECD 404 guidelines.

In the study with decene trimer hydrogenated (Pooles, 2009), 3 young adult New Zealand White Rabbits were dermally exposed to 0.5 mL of undiluted Linealene A-30H (semi-occluded patch with 2.5 square centimeter area) for 4 hours. Animals were observed for 7 days and irritation was scored by the method of Draize. There were no treatment related changes in body weight. Dermal irritation occurred in one rabbit with very slight erythema and oedema through 72 hours. At 72 hours the skin had lost its elasticity and flexibility. There was slight desquamation noted on day 7 in one rabbit. There were no effects observed in the other two rabbits. The mean erythema and oedema score were both reported as 0.33.

 

In the study with 1-dodecene dimer with 1-decene, hydrogenated (Dougherty, 1989), dermal application of 0.5 mL Oronite XS 101 to 6 young adult female New Zealand White rabbits produced mean erythema scores of 0.57 and 0.91 and mean oedema scores of 0.00 and 0.00 (intact and abraded skin, respectively). Flaky skin was observed in some animals up to day 7, but was absent by day 14. No other signs of clinical toxicity were reported.

 

Based on the weight of evidence from the aforementioned dermal irritation studies, poly alpha olefin substances, including 1-decene trimer, hydrogenated and tetramers, are not considered to be skin irritants and do not meet the criteria for classification and labelling for this endpoint.

 

There was no evidence of corrosive effects in any of these investigations.

One key eye irritation study was identified (Doyle, 1988). In this primary eye irritation study, 0.5 mL of Emery 3004 (undiluted) was instilled into the right eye of 6 naïve female New Zealand White rabbits for 24 hours. Eyes of the test animals were not rinsed post exposure. Animals then were observed for 72 hours and irritation was scored by the method of Draize (1959).

 

Two animals showed signs of conjunctival erythema; for one, signs cleared up by 72 hours, while for the other, signs appeared at 72 hours. Based on the reported results, Emery 3004 is not an eye irritant. Based on the results from this study, 1 -decene trimer, hydrogenated and tetramers is not considered to be ocular irritants and is therefore not classified or labeled for this endpoint.

Justification for classification or non-classification

1 -Decene, trimer, hydrogenated and tetramers is not considered to be a skin irritant and does not meet the criteria for classification and labelling for this endpoint.

1 -Decene trimer, hydrogenated and tetramers does not meet the criteria for classification and labelling as an eye irritant as defined by EU regulatory guidelines.