1-Dodecene, polymer with 1-decene and 1-octene, hydrogenated

Endpoint summary

Description of key information

Two read-across dermal irritation studies (OECD 404) were identified from decene trimer hydrogenated and 1-dodecene dimer with 1-decene, hydrogenated. Neither test material was identified as a dermal irritant in rabbits following 4 hour semi-occlusive exposures.
Two read-across eye irritation studies (OEC 405) was identified. Both test materials, 1-decene trimer, hydrogenated and tetramers as well as 1-dodecene dimer with 1-decene, hydrogenated, were 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. These two studies are discussed in further detail below and are the only studies presented in the table above because they were the only studies used in the evaluation of classification and labeling. 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.

 

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-dodecene, polymer with 1-decene and 1-octene, hydrogenated, 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.

 

With regard to eye irritation, two read-across studies were identified. For 1-decene trimer, hydrogenated and tetramers, 0.5 mL of Emery 3004 (undiluted) was instilled into the right eye of 6 naïve female New Zealand White rabbits for 24 hours (Doyle, 1988). 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. 

 

Another read-across eye irritation study was identified from 1-dodecene dimer with 1-decene, hydrogenated (Dougherty, 1989). In this primary eye irritation study, 0.1 millilitres of undiluted Oronite XS 101 was instilled into the conjunctival sac of one eye of nine young adult male New Zealand White rabbits for 72 hours. No evidence of corneal opacity or iris irritation occurred in either washed or unwashed eyes. Moderate to severe conjunctival redness was apparent in the unwashed eyes of rabbits 1 hour post-exposure. Moderate conjunctival redness was also seen at the 1 hour observation in treated eyes that were rinsed with water 30 seconds after instillation of Oronite XS 101. The redness in treated rabbit eyes decreased by the 24-hour observation and was completely absent at the 48 and 72-hour observation. Slight conjunctival redness was also observed in rinsed control eyes, 1 and 24 hours post rinsing.  In this study, Oronite XS 101is not an eye irritant based on an average Primary Irritation Score of 0.2 to 0.4 in unwashed and washed eyes, respectively, over 24, 48, and 72 hours.

 

Based on the results from these studies, it can be inferred that 1-dodecene, polymer with 1-decene and 1-octene, hydrogenated is not considered to be an ocular irritant and is therefore not classified or labeled for this endpoint.

Justification for classification or non-classification

1-Dodecene, polymer with 1-decene and 1-octene, hydrogenated does not meet the criteria for classification and labelling as a skin irritant under EU Dangerous Substances Directive 67/548/EEC or CLP EU Regulation 1272/2008 based on evaluation of the overall mean erythema and oedema scores from skin irritation studies with structural analogues.

 

1-Dodecene, polymer with 1-decene and 1-octene, hydrogenated does not meet the criteria for classification and labelling as an eye irritant as defined by EU Dangerous Substances Directive 67/548/EEC or CLP EU Regulation 1272/2008 based on read-across studies to structural analogues which were not irritating to the eyes of rabbits.