“Something bad has happened. I’ve got eyelash extensions,” singer and actress Kristin Chenoweth confessed on the "Late Show with David Letterman" last year while wearing large dark sunglasses, and visibly drowsy on Benadryl. “Here’s the problem: The glue has formaldehyde in it, and I’m allergic,” Chenoweth said. “I swelled up and I’m sneezing. . . . It looks like I have lips on my eyelids.”
The Broadway star is far from alone in her quest for longer, thicker eyelashes. Women have been enhancing their lashes since before the days of Cleopatra. Mascara, marketed since 1917, is a multibillion-dollar industry. False eyelashes went mainstream in the 1960s (thanks in part to Twiggy). The market has benefited from promotion by celebrity trendsetters including Nicki Minaj and Rihanna. The Kardashian sisters recently announced their line of false eyelashes and tweeted, “Faking fuller lashes are a thing of the past. For 2013 faux lashes are being worn BIG and without apology.”
But the quest for beauty can come at a price. Eyelash extensions—single synthetic fibers glued one by one to natural eyelashes—are usually fixed in place by formaldehyde-based adhesives or other biologic glues. The adhesives can cause allergic reactions, as can the solvents used to remove them. In addition, cosmetic eyelash enhancers carry a risk of bacterial and fungal infection.
Eyelash extensions have also been reported to cause irritation to the conjunctiva (conjunctivitis) or cornea (keratitis). The irritation can be caused by direct contact from the lashes themselves or hypersensitivity to the substances used to attach them. Among beauty treatments, eyelash extensions account for the greatest number of eye-clinic consultations in Japan, where they have been very widely used.