Dip powder (also known as SNS, for the brand Signature Nail Systems) nails have grown in popularity, but before trying this trendy new service, there's at least one woman warning to proceed with caution.

Most dip powders are a combination of a glue-type liquid and powder that hardens when it hits the air, and leaves long-lasting color on your -- nails minus the need for any ultraviolent (UV) lighting to cure or dry. There also isn't the pungent smell that's often associated with gel or acrylic.

You simply dip your nail in a colored powder of your choice, and seal it with a top coat of polish. The finished look can last anywhere from two to four weeks.

"Just like classic acrylic systems, there are two crucial parts to a dipping system: the liquid hardening agent and the powder," according to chemist Doug Schoon as noted in Refinery29.

"In a dip system, the liquid is based on cyanoacrylates," says Schoon. "They are used for suturing wounds in the body and eyelash glue. When they react with moisture in the air or the nail, it causes them to harden."

On July 6, Robin C. Medley posted a series of photos on Facebook showing what appears to be wounded skin as well as infected nails being dipped in powder.

"For the ones that love dip nails...this is why I don’t do dip," Medley wrote in a caption. "U never know what the previous person had going on with their nails, don’t risk infection with the latest trends."

Medley's post has since been shared more than 20,000 times -- with many people commenting on how unsanitary and frightening the dip powder service can be.

Elle reports that due to sanitation concerns, many salons don't carry the treatment.

"It is incredibly unsanitary for multiple clients to dip their fingers in the same container of powder, even pouring the product over multiple clients' nails and allowing the product powder to fall back into the container is an easy way for nail infections to be passed between clients," says licensed nail technician Harli G.

She continues, "If you notice techs applying the dip powder in either of those ways, leave and go to a different salon."

Experts agree, that a safer alternative is to have the powder poured over the nail base rather than dipping your nail in a jar.

Another suggestion is to bring your own dip powder.

Brands such as SNS - Signature Nail Systems, OPI, Red Carpet Manicure, and Kiara Sky Nails carry dip powder products you can shop for and try yourself or bring to your local salon.