Contact Lens Dangers

Contact lenses are generally safe, but the potential exists for hazardous effects. According to an article published in a 2004 issue of "Contact Lens Spectrum," up to 80 percent of all contact-lens complications are the result of poor practices by lens wearers.

Contaminated Lens Cases

• Many contact lens wearers do not clean their lens cases properly and do not replace them regularly. According to EyeCareSource.com, a study in 1997 showed that of 141 contact lens wearers, 70 percent of their cases were contaminated. This can cause eye infections.

Replacement Issues

• Additionally, a 2009 survey by the University of Waterloo in Canada found that more than half of two-week lens replacement wearers and 15 percent of daily-replacement wearers wore their lenses longer than the manufacturer advised. This can cause material breakdown and make the lenses difficult to clean effectively.

Improper Lens Cleaning

• People who use tap water or homemade solutions to clean their lenses or do not clean them properly can develop acanthamoeba keratitis, a serious corneal infection. Other people at risk are those who put the lenses in their mouth or swim or take showers while wearing contact lenses.

Sleeping with Lenses

• Wearing contact lenses while sleeping is a common cause of painful corneal ulcers, even if the lenses have been approved for this use.

Unapproved Lenses

• Although contact lenses sold in the United States must be approved by the Food and Drug Administration (FDA), people can buy cosmetic-colored contact lenses online from other countries. Some of the colors used are toxic. The FDA has received reports of corneal ulcers associated with wearing these lenses.

Solution Recalls

• Additionally, four contact lens cleaning products and solutions have been recalled after being linked to an increase in eye infections.