The A.A.O. recommends caution to consumers.
The American Academy of Ophthalmology (A.A.O.) has issued a warning advising consumers to be very careful with coloured, over-the-counter (OTC) contact lenses, which are widespread and popular especially around Halloween time.
In fact, data from a study published in the September issue of Eye & Contact Lens: Science & Clinical Practice some tested samples tested positive for chemicals that can damage the eyes.
Traces of chlorine were detected in three types of contact lenses, while iron residues were found in four pairs of lenses. These chemicals may derive from the dyes used to give the lenses their colour or other aesthetic effects. One pair of lenses released chlorine after a routine wash, causing researchers to be alarmed about possible toxic effects on the eye. The researchers also found that the dyes printed or applied on some cosmetic lenses create an uneven surface. This rough surface could scratch the eye, potentially creating a pathway for bacteria that can cause infections, such as keratitis and corneal ulcers, or even blindness.
4 out of 5 of these lenses could not be legally sold in the US as they have not been approved by the FDA (Food and Drug Administration), however they are easily available online through numerous websites.
For this purpose, the A.A.O. has prepared guidelines for the purchase of coloured contact lenses:
- Only buy cosmetic lenses from retailers that require a prescription and sell FDA-approved material.
- If you do not already have a prescription for contact lenses, visit an ophthalmologist or optometrist for a valid prescription and an eye examination.
- Even those with perfect vision should be examined and the appropriate lens indicated by an eye health specialist. Inappropriate lenses can scratch the ocular surface and create an opening for infection.
- Redness, swelling, excessive discharge, pain or discomfort can be signs of an eye infection. If you present with these symptoms, visit an ophthalmologist immediately. Untreated eye infections can cause blindness.
For more details see:
The A.A.O. page of information on cosmetic lenses
The article "Scanning Electron Microscopy Findings With Energy-Dispersive X-ray Investigations of Cosmetically Tinted Contact Lenses".
Dr. Carmelo Chines
Direttore responsabile
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