While the desire for clear vision during a beach vacation or ocean swim is understandable, the definitive answer to wearing contact lenses in the ocean is a strong recommendation against it. Eye care professionals universally advise avoiding all water exposure, including ocean water, while wearing contacts due to the significant risk of infection and physical complications. The ocean environment presents a unique combination of biological and material-based threats that can rapidly compromise eye health and lens integrity. This caution applies to both accidental splashes and intentional swimming, prioritizing eye safety above visual convenience.
Physical Effects of Seawater on Lenses
Seawater is a hypertonic solution, meaning it has a higher salt concentration than the natural tear film of the eye. Soft contact lenses are designed to absorb moisture and maintain a specific shape based on the eye’s natural salinity. When exposed to ocean water, the lens material reacts by changing its shape, a process that can lead to immediate discomfort and blurry vision.
The influx of salt water can cause the soft lens to tighten, sometimes making it adhere more strongly to the cornea. This adherence makes the lens difficult to remove and increases the risk of causing microscopic abrasions on the corneal surface upon removal. The altered fit also allows sand, silt, or other fine debris found in the ocean to become trapped between the lens and the eye, which can easily scratch the cornea. Waves and currents significantly increase the chance of the lens shifting out of place or falling out entirely.
The Threat of Serious Eye Infections
The most serious danger of wearing contact lenses in the ocean is the elevated risk of contracting a severe microbial infection. Ocean water, even when appearing clean, is an unsterile environment teeming with microorganisms, including bacteria, fungi, and parasites. Contact lenses, especially soft ones, are porous and act like microscopic sponges, readily absorbing and trapping these pathogens directly against the eye’s surface.
The primary concern is the presence of the microscopic parasite Acanthamoeba, which is naturally found in virtually all water sources, including seawater. When this organism attaches to a contact lens, it can lead to a rare but devastating condition called Acanthamoeba keratitis (AK). This infection targets the cornea, the clear, dome-shaped front surface of the eye, and is notoriously difficult to diagnose and treat.
Contact lens wearers account for over 85% of AK cases in developed countries because the lens provides a perfect vehicle for the pathogen. The parasite can burrow into the corneal tissue, causing extreme pain, redness, light sensitivity, and severely blurred vision. Treatment for Acanthamoeba keratitis can last for many months, often involving intensive and specialized antimicrobial therapy. In severe cases, the infection can result in permanent vision loss or necessitate a corneal transplant to restore sight.
Recommended Safe Alternatives
For those who require vision correction to safely enjoy water activities, several alternatives exist that eliminate the risks associated with contacts. The most secure option is using custom-made prescription swimming goggles, which provide a watertight seal and clear vision tailored to the wearer’s exact refractive error. Ready-made goggles with “step diopters” are also available for common prescriptions, offering an affordable, off-the-shelf alternative.
If contacts must be worn in conjunction with water exposure, the safest practice is to use daily disposable lenses and pair them with tightly fitted, waterproof swimming goggles. The contact lenses must be removed and immediately discarded upon exiting the water, minimizing the duration of potential contamination. If ocean water accidentally contacts the eyes while wearing any type of lens, the contaminated lenses should be removed and thrown away immediately, and the eyes should be allowed to rest, ideally with glasses, before wearing a fresh pair.