Fast Five Quiz: Tattoos

Brett Sloan, MD


September 10, 2020

Although recent studies have found that fewer tattoo inks now contain metallic pigments, photo-aggravated tattoo reactions have been most commonly caused by yellow and red pigments. Edema and erythema may develop upon exposure to sunlight. Although the mechanism is not clear, cadmium sulfide is the light-sensitive material used in photoelectric cells; therefore, the reaction is believed to be phototoxic.

In contrast to hypersensitivity reactions to red and yellow tattoos, reactions to pigments used to create green, blue, and black tattoos are much less common. Chromium in green tattoo pigment has been associated with localized eczematous reactions at the site of the pigment, eczema of the hands, and generalized eczematous reactions. Individuals may have been sensitized initially by exposure to cement. Patch testing to 0.5% potassium dichromate is often positive. Previously quiescent green-colored tattoos may become inflamed during patch testing in potassium dichromate–sensitive individuals.

Blue tattoos that contain cobalt aluminate have been linked to localized hypersensitivity reactions and (rarely) spontaneous development of uveitis.

Allergic reactions to black tattoo pigment are very rare. Presumably, individuals with this allergy are sensitive to carbon.

Read more about photo-aggravated tattoo reactions.


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