Scientists at the Centre for Disease Control and Prevention, based in Atlanta, Georgia, identified 101 individuals who had reported adverse reactions after receiving the treatment, and went on to interview and study some 92 women. The investigation was prompted after FDA records revealed that between 1998 and 2003 only five reports of adverse reactions to permanent makeup procedures were reported, whereas from 2003 more than 150 reports of adverse reactions were made. In a report published in the New England Journal of Medicine, the science team said that more than nine out of 10 of the volunteers they studies had swelling and tenderness as a direct result of the ink injections associated with the treatment. Nearly as many of the individuals reported itching and four out of five had also reported bumps or other skin outbreaks. What's more the allergic reaction were also long-lasting, remaining visible for anything from five months up to three years. Although the number of people having permanent makeup treatments in the US is currently unknown, it is becoming an increasing popular means of enhancing features such as the eyebrows, eyelids and lips, appealing to on-the-go and sporty individuals, as well as elderly or disabled women who find makeup hard to apply. The treatment is administered by intradermally injecting inks that mainly contain pigments and suspending agents to the required area. In fact the treatment is very similar to getting a tattoo Controversy has surrounded such treatments in the US before, after the American Institute of Intradermal Cosmetics recalled and replaced inks used in its permanent makeup treatments following a disproportionate number of complaints to the FDA back in 2004. Currently the inks and dyes used in permanent makeup are not approved by the FDA, but the government agency is currently re-evaluating the procedure as a reaction to the growth in popularity. In fact the FDA says that, rather than having issues with the ink, its main concern is the use of unsterilized equipment that can cause the spread of infectious diseases.