What is it? Pseudomonas is a common form of bacteria that can turn a client’s nails green. The bacteria can be present almost anywhere — on plants and animals, in soil, even in water. Advanced cases will appear as dark green or even black spots on the nail.

How do you get it? Most of the time, the nail bed and the nail plate do not provide a suitable environment for these bacteria to grow. There are times, however, when conditions are perfect, and bacteria grow either on top of the nail bed and under the natural nail, or on top of the natural nail and under an enhancement. Because these bacteria are so prevalent, all it takes is for the skin under the nail to be compromised and then exposed to the pseudomonas bacterium. Alternatively, when product is applied over a nail plate that holds pseudomonas bacteria, it creates a nearly oxygen-free environment — in which these bacteria thrive. They eat the oils and excrete an extremely dark substance. This is what we see when the nail turns green.

How is it treated? The treatment for green nails is to remove the enhancement, and trim, clean, and disinfect the nail to kill the pseudomonas bacteria. Some doctors will suggest a 1% acetic acid treatment, an antibiotic, or an antifungal cream.

What can a tech do? Prevention is the best treatment. The first step in prevention is a clean environment and proper application. Protect yourself and your client by adhering to industry standards. Techs need to be vigilant about thoroughly cleaning their implements, all salon surfaces, their own hands, and the hands and nails of their clients. Careful cleaning and disinfection of the nail surface is essential before applying product. Otherwise, techs could unknowingly trap bacteria between the product and the natural nail. If any of your implements come into contact with an infected nail, immediately clean and disinfect them, wash your hands, your client’s hands, and the surface of your work area. Pseudomonas infection is considered a medical disorder and the client should be referred to a doctor. Techs may want to remove the product from the nail, but if the nail has an infection, they are legally bound to avoid any form of treatment.

What else? In the case of pseudomonas bacteria causing green spots under the nail product, the cause is always one of two things: Either the bacteria was on the nail plate when the product was applied (due to dirty implements or poor prep) or product adhesion was insufficient. When adhesion is insufficient, pseudomonas bacteria can find their way under the product through a chip, crack, or lift. Remember also to educate your clients about nail care. During a client’s first appointment, instruct her not to pick, pry, or glue her nails. Don’t wait until she has glued a cracked or broken nail to tell her about trapped bacteria and green spots. When a client glues the nail, she increases the risk of trapping bacteria under the nail.

Doug Schoon contributed to this article.


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