What ingredient is least likely to have a negative impact on the cornea?

The ingredient least likely to have a negative impact on the cornea is Sorbic Acid. This substance is a widely used preservative, particularly in food and cosmetics, due to its antifungal properties. Its low toxicity profile makes it a favorable choice for use in formulations that come into contact with ocular tissue. Sorbic Acid is generally well-tolerated and has a minimal potential for causing irritation or adverse effects on the cornea, especially compared to other alternatives.

Thimerosal, Hydroxypropyl Methacrylate, and Chlorhexidine, on the other hand, have been associated with various ocular side effects. Thimerosal, for example, is a mercury-containing compound that can cause allergic reactions and irritation of the eyes. Hydroxypropyl Methacrylate is used in contact lens materials and can pose risks if not properly polymerized, leading to potential toxicity. Chlorhexidine is an antiseptic that, while effective against bacteria, can lead to corneal toxicity and irritation when it comes into contact with the eyes.