Pseudoephedrine

Endpoint summary

Description of key information

Skin irritation, rabbit (OECD TG 404, no GLP): not irritating
Eye irritation, rabbit (OECD TG 405, no GLP): not irritating

Additional information

Skin irritation

The skin irritating potential of the read-across substance (+)-Pseudoephedrine hydrochloride was examined in 2 male and 1 female Vienna White rabbits (OECD TG 404, no GLP). The animals were exposed to about 0.5 g of a 80% test substance solution for 4 hours under semiocclusive conditions. After 4 hours slight erythema (3/3 animals) and edema (2/3 animals) were observed, but were fully reversible within 24 h. The mean for erythema and edema over 24, 48, and 72 h was therefore 0.

The results indicate that (+) Pseudoephedrine when tested as a hydrochloride salt (pH ca. 6) is not irritating to the skin. Due to the higher pH value of the free base (pH ca. 10) a skin irritating effect can, however, not be excluded.

Eye irritation

The eye irritating potential of the read-across substance (+)-Pseudoephedrine hydrochloride was examined in 2 male and 1 female Vienna White rabbits (OECD TG 405, no GLP). The animals were exposed to about 0.1 mL (37 mg) of test substance, and no rinsing of the eye was performed. Observations were performed after 1, 24, 48, and 72 h. Conjunctivae redness (well-defined) and chemosis (slight) was observed in all 3 animals after 1h. The mean for opacity-degree of density was 0.1, mean for conjunctivae redness was 0.3, mean for chemosis was 0.1. All findings were fully reversed within 48 h.

The results indicate that (+) Pseudoephedrine when tested as a hydrochloride salt (pH around 6) is not irritating to the eyes. Due to the higher pH value of the free base (pH ca. 10) an eye irritating effect can, however, not be excluded.

Respiratory irritation

There exists no standard test method for the assessment of respiratory irritation. Thus, findings for skin/eye irritation and acute inhalation toxicity are reviewed. The test substance has been shown not to be irritating to the skin and the eyes. Results from an acute 4-hour inhalation study revealed signs of toxic stress including nose discharge (reddish), salivation, accelerated respiration while exposition. After exposition smeared fur (bloody, near head), accelerated/irregular respiration, and respiratory sounds were observed.

All symptoms were reversible within 5 (males) and 8 (females) days. Pathological observations in the dead animals revealed no abnormalities. In conclusion, it can not be excluded that the test substance is an irritant to the respiratory tract based on the current information. Human data or animal data from repeated inhalation toxicity studies are not available for further assessment of respiratory irritation.

Justification for classification or non-classification

Dangerous Substance Directive (67/548/EEC)

- Classification required for irritation/corrosion as irritating to eyes, respiratory system and skin (Xi; R36/37/38).

Classification, Labeling, and Packaging Regulation (EC) No. 1272/2008:

- Classification required for Skin irritation/corrosion, Serious eye damage/eye irritation and Specific organ toxicity - single exposure (Skin Irrit. 2, H315; Eye Irrit. 2, H319; STOT SE 3, H335).