color additives must obtain batch certification from the FDA when used in US-marketed cosmetics. The FDA has classified 65 types of color additives as \"permissible\". Their availability depends on the eye area and general (including lipstick) and external use. The FDA has also set the usage limit for some color additives.  
Although color cosmetics directly contact the skin and must therefore meet all safety requirements, many cosme with unusable and unsafe pigments capable of causing side effects such as pigmentation have previously been marketed, which highlights the need for appropriate regulation. In the Republic of Korea, cosme manufacturers are required to list all the ingredients of a given product. The Ministry of Food and Drug Safety has listed the colorants allowed for use in color cosmetics as well as the related standards and analytical methods. In particular, the Cosmetics Act lists 129 pigments that can be used in cosmetics. However, the use of these pigments is subject to restrictions depending on the type of cosmetics and/or the targeted skin area. In addition, standards for ingredients that cannot be used in cosmetics and those that can be used only under certain restrictions are also designated and managed through timely notices. The above act also prohibits approximately 90 carcinogenic or harmful colorants from use in color cosmetics.  
Previous studies on pigment analysis employed high-performance liquid chromatography (HPLC), ultra-high-performance liquid chromatography (UHPLC), ultra-high-performance supercritical fluid chromatography, and liquid chromatography-electrospray ionization tandem mass spectrometry [12; 13; 15; 21; 22; 23; 24; 25; 26; 27; 28; 29; 30], but have mostly focused on food or textiles and not cosme. [PERSON] et al. used liquid chromatography-tandem mass spectrometry (LC-MS/MS) to simultaneously analyze nine water-soluble pigments found in cosmetics/personal care products and detected seven of these targets at levels of 0.054-580 \(\upmu\)g/g [24]. In another work, [PERSON] et al. analyzed 19 synthetic dyes used in confectionaries and cosmetics using LC-MS/MS [11] and detected nine targets at levels of 0.232-989 \(\upmu\)g/g in the 24 tested samples. [PERSON] et al. analyzed 63 pigments in cosmetics (eye shadow, eyeliner, lipstick, blusher, toothpaste) using UHPLC coupled with quadrupole-Orbitrap high-resolution mass spectrometry [10] and detected 11 targets (Basic Violet 1, Basic Violet 10, and Basic Violet 3, etc.) at levels of 0.0190-13.2644 mg/kg in the 26 tested samples.  
The growing interest in long-lasting cosmetics such as tattoo lipsticks, tattoo eyebrows, and hair tints has increased the incidence of the related side effects. Currently, regulatory authorities manage products by issuing various guidelines; however, no effective analysis methods for illegal colorants in cosmetics have been established. This study contributes to the safety of color cosmetics by developing a method for detecting prohibited colorants therein (Figure 1). Unlike previous investigations, the present work uses HPLC coupled to a diode array detector (HPLC-DAD) and UPLC-MS/MS to develop an analytical method for analyzing illegal colorants and fragmentation of pigments using liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS).