Registration Dossier

Administrative data

Description of key information

Skin irritation study in rabbits and eye irritation studies in rabbits

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

Skin irritation study in rabbits:

Dipropylene glycol n-propyl ether (DpnP, purity 99.32% by weight) was evaluated for primary dermal irritaion. Aliquots of 0.5 ml of DPnP were applied for four hours to the intact skin on the back of six New Zealand White rabbits. Very slight erythema was observed on two of the six rabbits within 30 minutes of test material removal. Three of the six rabbits at 24 and 48 hours had very slight erythema. Very slight erythema was present on one of the six rabbits 72 hours after test material removal which was resolved by test day 7.

One of the rabbits patch was inadvertently caught under the tape and was held very tightly in place for the four hour exposure. As a result of this error in application technique, the rabbit had severe erythema and gradually diminishing edema for the remainder of the study, neither of which were interpreted to be compond related. The test was terminated 14 days after test material removal. Dermal application of 0.5 ml dipropylene glycol n-propyl ether had no effect on body weight. Based on the results of the study, dipropylene glycol n-propyl ether will not be classified as irritating.

Eye irritation study in rabbits:

There are two studies available for this substance. In the first study, Dipropylene glycol n-propyl ether (DPnP), purity of 99.32% (by weight), was assessed for the potential to cause ocular irritation after instillation of a 0.1 ml aliquot into the conjunctival sac of the right eye of six New Zealand White rabbits. Examination of the eyes revealed slight to moderate redness of the conjunctiva, moderate to marked chemosis, and marked discharge one hour after dosing, in all animals. Five of the six animals had very slight to slight opacity, at the one hour read.

 

The redness, chemosis, discharge and corneal opacity diminished or resolved in all animals during the following three days. All ocular effects were resolved by seven days post dosing, and the test was terminated. Instillation of dipropylene glycol n-propyl ether into the eye had no effect on body weight. Based on the results, dipropylene glycoln-propyl ether can be classified as a mild eye irritant.

In the second study, 0.1 ml of ARCOSOLV® DPnP (Dipropylene Glycol mono-n-Propyl Ether) was instilled into the lower conjunctival sac of the right eye. The eyelid was held closed for approximately 1 second and released. A washout followed, consisting of 60 mL of deionized water over a period of approximately 30-40 seconds, commencing approximately 30 seconds after dosing. The left eye of each animal was manipulated in an identical manner to simulate the dosing of the right eye and served as a contralateral control. The eyes were examined for ocular reactions in accordance with the method of Draize at approximately 1, 24, 48 and 72 hours after dosing and on study days 4, 7, 10, 14, 17 and 21, if irritation persisted. Sodium fluorescein was used to aid in revealing possible corneal damage at 24 hours and at all subsequent observations.

Conjunctival irritation (grades 1, 2, 3 and 4) were noted for all animals. Positive corneal irritation (grade 1) was noted for 1 animal 48 hours post-dosing and subsided by the 72 hour post-dosing observation. Conjunctival irritation noted at study termination (study day 21).

Based on the results, ARCOSOLV® DPnP (Dipropylene Glycol mono-n-Propyl Ether) can be classified as a mild eye irritant., however the weight of evidence indicates that the substance will not be classified for eye irritation.

Justification for classification or non-classification

Skin irritation study in rabbits:

Based on the results of the study and Guidance to Regulation (EC) No. 1272/2008 on Classification, Labelling and Packaging of substances and mixtures, dipropylene glycol n-propyl ether will not be classified as irritating.

Eye irritation study in rabbits:

Based on the results of the studies and Guidance to Regulation (EC) No. 1272/2008 on Classification, Labelling and Packaging of substances and mixtures, dipropylene glycol n-propyl ether will not be classified as an eye irritant.