Which of the following is a type of deposit that may be found on contact lenses?

• A. Protein
• B. Calcium
• C. Lipids
• D. Bacteria

Answer: (A)

Proteins from the tear film readily accumulate on contact lenses, making protein deposits the most common type of buildup you’ll encounter. Tear proteins like lysozyme and albumin can adhere to lens surfaces, especially when cleaning is insufficient or the lens material tends to attract proteins. These deposits can blur vision, alter surface properties, and may be addressed with enzymatic cleaners designed to remove protein buildup. Lipids and minerals can also deposit under certain conditions, and bacteria can adhere to lenses, but bacteria are living organisms rather than surface deposits. So, protein deposition is the typical type of lens buildup.