Getting a tattoo is a popular method of self-expression, but it also comes with some health risks. Understanding the current concerns and risks about tattoo ink will help you make a better-informed decision about decorating your body.

When most people think of the dangers of tattoos, they imagine artists in seedy tattoo shops using contaminated needles in an unsanitary environment. While the dangers of HIV and other diseases does exist in the tattooing world, the inks used pose more widespread risks. Tattoo inks can have several effects on the skin and other areas of the body.

Regulation
According to TattooDesigns.org.uk, the Food and Drug Administration (FDA) has not approved many of the pigments used in tattoo inks for contact with the skin. Since there is little federal oversight of the products used in tattooing, the composition, quality and ingredients of tattoo inks can vary significantly. The FDA also does not require tattoo ink manufacturers to disclose the ingredients used in their inks.

Contaminants
Since the FDA allows tattoo ink manufacturers to produce inks without disclosing ingredients, the spectrum of contaminants is unknown. TattooHealth.org references a study conducted by the Institute for Consumer Health and Protection that found that some tattoo inks contained sulphides, oxides, selenides and metallic salts. The study also noted that many chemicals appearing in tattoo inks were originally intended for use in printing and writing inks, as well as in automotive paints.

Short-Term Effects
The pigments, metals and chemicals in tattoo inks can promote skin infections, according to TattooHealth.org. Even under the most sanitary conditions, skin that has been recently tattooed can develop a serious infection. Some people also experience allergic reactions after tattooing, as well as cosmetic scarring.

Long-Term Effects
Although there are few long-term risks, tattoo inks can complicate magnetic resonance imaging (MRI) tests years after a person is tattooed. The reaction of tattoo inks to MRI pulses can cause swelling or burning sensations in tattooed areas, according to TattooHealth.org.

Allergic Reaction
An allergic reaction to tattoo ink is possible when you receive a tattoo, though allergic reactions are rare. Red tattoo ink, because some red inks are made with mercury or cinnabar, is the cause of most allergic reactions from tattoo ink, according to a study published in a 2009 issue of "Journal of Cosmetic Dermatology." If you are allergic to shellfish due to the mercury, tell your tattoo artist before receiving a tattoo with red tattoo ink. While a tattoo is healing, ulcers or a rash may form on your tattoo if you are experiencing an allergic reaction to the tattoo ink. Scabs are normal during the healing of a tattoo and should not be confused with ulcers or a rash on or around the tattoo. If an allergy to ingredients in tattoo inks develops in the future, your healed tattoo may react with swelling, itching or a small rash.

Disease Transmission
Disease transmission is possible with tattoo inks if the tattoo artist is not a licensed professional. Professional tattoo artists disperse ink into disposable caps to avoid contaminating an ink bottle and never place ink that is in a contaminated ink cap back into the bottle. Any leftover ink after a tattoo procedure is disposed into a biohazard trash can to prevent the spread of infection or disease. The needle on a tattoo machine breaks the skin to insert the tattoo ink. If the tattoo ink is contaminated from a previous client's infected blood, it is possible for you to contract diseases such as hepatitis B or C or HIV, according to Mayo Clinic.com. Receiving a tattoo from someone that works outside a tattoo shop, such as in the home or at a party, is not safe and should be avoided to lessen the risk of disease transmission from tattoo ink.

There is one risk from tattoos, however, over which you may not have much control. In rare cases, skin can reject the tattoo ink.

Can Skin Reject Tattoo Ink?
The body rejects things by creating an allergic reaction to a substance it registers as harmful, even if the substance is not, says Mayo Clinic. Such is the case when skin rejects tattoo ink, usually with an itchy, red rash in the tattooed area. An allergic reaction to tattoo ink is rare, but it can hit even years after you get a tattoo. Sometimes, medications work for treatment, but in other cases, the best bet is to get the tattoo removed. Skin can also react soon after a tattoo by breaking out in itchy, raised bumps known as granulomas or form keloids, which are large, raised areas of scar tissue.

Cause
Allergic reactions to tattoos come about because of some of the substances used in ink pigments, Mayo Clinic and Dermatology Insights say. Some inks contain cadmium, mercury or other substances and compounds that some people's bodies deem as harmful. Red ink is one of the top culprits for allergic reactions, although neither Mayo Clinic nor Dermatology Insights note any specific components in red ink that differ from other colors and cause the higher rate of rejection.

Approved Pigments
Tattoo inks come in a huge palette of colors, ranging from Bahama blue to banana cream yellow, ruby red to titanium silver. More than 50 different pigments and shades are on the market, the U.S. Food and Drug Administration says, with new ones added regularly. The FDA has approved exactly zero for injection into the skin. This does not mean, however, all unapproved pigments will cause an adverse reaction. It means the FDA has been falling down on the job, which it readily admits on its website.

Removal?
The variety of possible chemicals present in tattoo inks makes tattoo removal a difficult task. Even laser removal, which is designed to break up pigments, might not be able to remove some inks. This means that a tattoo wearer might need to have a cover-up tattoo done to hide the resistant inks. Cover-up tattoos are usually much larger than the designs they cover because additional skin area is need to camouflage the old ink, according to Dreamland Creations.