An excess of which ion can lead to jelly bumps on soft contact lenses?

An excess of calcium ions can lead to the formation of jelly bumps on soft contact lenses, a condition often referred to as "calcium deposits." When the concentration of calcium in the tear film increases, it can precipitate out on the lens surface, causing these unsightly bumps. This occurs because calcium ions have a tendency to interact with the polymer materials in soft contact lenses, leading to the accumulation of deposits.

These jelly bumps can be problematic as they not only affect comfort for the wearer but can also impair vision and increase the risk of ocular irritation and infection. Maintaining proper pH and electrolyte balance in the tear film is crucial for preventing such occurrences when wearing soft contact lenses.

Other ions listed, such as sodium, bicarbonate, and chloride, do not typically lead to this type of deposit formation on contact lenses, which further emphasizes the unique role calcium plays in this context.