Watching a contact lens slip from your fingertip and land on the floor is a common experience for lens wearers. Whether you can still use it depends on the lens material, the surface it landed on, and the rigorous steps taken immediately after the drop. Introducing a contaminated surface to the eye can lead to severe complications. You should never reinsert the lens without cleaning it first, as the microscopic environment of any floor harbors organisms that pose a significant threat to ocular health. The subsequent cleaning and disinfection process is the determining factor for the lens’s safety.
Understanding Contamination Risks
Dropping a soft contact lens onto any household surface instantly exposes it to a complex bio-hazard environment. The porous material of a soft lens allows microscopic contaminants to adhere easily, creating a direct pathway to the cornea. Floors, even those that appear clean, are home to various microorganisms, including bacteria, fungi, and protozoa.
One concerning bacterial risk is Pseudomonas aeruginosa, a highly virulent organism that frequently causes microbial keratitis, a serious corneal infection. The lens acts as a shield, trapping these bacteria against the eye’s surface, allowing them to multiply rapidly. Fungi, such as Fusarium species, also exist on surfaces and can cause infections that are particularly difficult to treat.
A more severe threat is the protozoan Acanthamoeba, which is ubiquitous in soil and water sources. This microscopic organism causes Acanthamoeba keratitis, a rare but extremely painful and sight-threatening infection. The soft lens material allows the amoeba to cling to its surface, and the subsequent infection often requires intensive, long-term medical treatment.
The Proper Cleaning and Disinfection Protocol
If you attempt to salvage a dropped lens, a strict, multi-step protocol must be followed to maximize the chances of successful decontamination.
Hand Washing and Initial Preparation
Before touching the lens, wash your hands thoroughly with soap and water, then dry them with a lint-free towel to prevent transferring oils or debris. Place the lens in the palm of your hand and apply several drops of fresh, approved contact lens solution. Never use tap water, which introduces the risk of Acanthamoeba and other microbes.
Mechanical Cleaning and Rinsing
Gently rub the lens back and forth with your index finger for 10 to 20 seconds. This rubbing action physically dislodges microorganisms and debris that may be resistant to the solution’s chemical action alone. After rubbing, rinse the lens thoroughly with a steady stream of fresh multipurpose solution to wash away the loosened contaminants.
Disinfection
The final step is complete disinfection, which requires a minimum soaking time in a clean lens case filled with fresh solution. The solution’s packaging will specify the required duration, typically at least six hours or overnight. This allows the chemical agents sufficient time to neutralize any remaining pathogens. Reinserting the lens before this minimum disinfection time is complete compromises its safety.
Situations Requiring Immediate Disposal
There are several scenarios where a dropped contact lens must be discarded immediately, regardless of cleaning efforts.
If you wear daily disposable lenses, they are designed for single use and their material is not robust enough to withstand the intensive cleaning and disinfection process. These lenses must be replaced with a new sterile lens.
Physical damage also necessitates immediate disposal, as tears, chips, or microscopic rips can harbor pathogens or scratch the delicate corneal surface. Inspect the lens carefully under a bright light before attempting any cleaning.
The surface on which the lens landed can be a definitive reason to discard it, such as a bathroom floor, which carries a high concentration of harmful bacteria.
A lens that has come into contact with water, such as being dropped into a sink or on a shower floor, should also be immediately disposed of. This is due to the severe risk of Acanthamoeba contamination, as this protozoan is highly resistant and commonly found in domestic tap water. If you have any remaining doubt about the lens’s cleanliness or notice discomfort upon reinsertion, discard the lens.