CBS NEWS -- With every new beauty business and service comes a warning. Today's focus is eyelash extensions.

Technicians glue synthetic fibers one by one to your natural lash line. Some adhesives contain formaldehyde, which can cause allergic reactions and even long lasting damage. Bacteria can also grow in fake lashes, leading to infections. And some customers can lose their real lashes from repetitive treatments

"What's very crucial is they need to clean their extensions, their eye area," says spa owner Paul Byun. "A lot of clients, they don't don't touch their extensions because they want them to last long."

Along with your own responsibility, there is the responsibility of the facility offering the service. Really look at the business to rate the cleanliness.

Right now, only Texas and Utah require technicians to get licensed solely for eyelash extensions. But in North Carolina eyelash extensions and services are part of the cosmetology program.

For any beauty service, you should know what to look for when it comes to licensing and facility cleanliness. Check out our stories:

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