In recent years, cosmetic tattoos [permanent make-up (PMU)] on eyelids, eyebrows and lips have become increasingly popular. However, most colorants are manufactured for non-medical purposes, without any established history of safe use in humans...Beauticians tended to use various PMU products, but all contained Pigment Red 181 (CI 73360). All patients tested showed a clear delayed reaction to Pigment Red 181 or the tattoo ink, or both, after prick testing. Histology indicated an allergic reaction. Each lip lesion slowly abated after several months of topical or systemic therapy with steroids in combination with tacrolimus, but none has yet completely resolved...In light of the severe and often therapy-resistant skin reactions, we strongly recommend the regulation and control of the substances used in PMU colorants (1).

References___________________________

(1) Permanent make-up colorants may cause severe skin reactions.
Wenzel SM, Welzel J, Hafner C, Landthaler M, Bäumler W.  -  Contact Dermatitis. 2010 Oct;63(4):223-7. doi: 10.1111/j.1600-0536.2010.01799.x.

CI 73360: what it is, cosmetic uses, safety and alternatives

CI 73360 is a chemical compound, also known as Red 30 or D&C Red 30, is a red pigment used in cosmetics, personal care products, and some pharmaceutical products to impart color.

It is classed chemically as a thioindigoid colour.

The name describes the structure of the molecule

• The CI (Color Index) numbering is a standardized system for classifying dyes. 
• "73360" is the specific number assigned to this particular red pigment.

Description of raw materials used in production

The exact composition and raw materials for producing CI 73360 may vary depending on specific production methods and companies. However, the production of organic pigments like CI 73360 often involves aromatic precursors and conducting chemical reactions to form the dye structure.

Synthesis process

The specific synthesis of CI 73360 is not available to the public due to industrial patents or trade secrets. However, the production of similar pigments often involves chemical reactions between aromatic precursors, followed by purification, grinding, and treatment processes to yield the final product.

What it is for and where

Cosmetics

It is a restricted ingredient as IV/100  a Relevant Item in the Annexes of the European Cosmetics Regulation 1223/2009. Substance or ingredient reported: 6-Chloro-2-(6-chloro-4-methyl-3-oxobenzo[b]thien-2(3H)-ylidene)-4-methylbenzo[b]thiophene-3(2H)-one

Cosmetics - Used as a coloring agent in various cosmetic products such as lipsticks, blushes, eyeshadows, and nail polishes.

Personal Care Products - Can be found in products like shampoos, body washes, and other body and hair care products where coloring is desired.

Pharmaceutical Products - Sometimes used to color pills and capsules to make them easily identifiable.

Safety

An impurity has been identified in the dye D&C Red 30 (1), it will be necessary to check over time if the production process has been modified to remove the impurity.

Alternatives

• Molecular formula: C₁₈H₁₀Cl₂O₂S₂
• Molecular weight: 393.31 g / mol
• CAS: 2379-74-0
• EINECS 219-163-6
• UNII    2S42T2808B
• DTXSID601045209

Synonyms:

• Pigment Red 181
• Pigment Yellow 181
• (delta,(sup2,2’(3h,3’h))-bibenzo(b)thiophene)-3,3’-dione,6,6’-dichloro-4,4’
• (2E)-6-chloro-2-(6-chloro-4-methyl-3-oxo-1-benzothiophen-2-ylidene)-4-methyl-1-benzothiophen-3-one
• Vat red 1
• Daltolite Pink FF
• Helindon Pink R
• Durindone Pink FF
• Fenidon Pink R
• Helindone Pink CN
• Indanthren Brilliant Pink R
• Calophyl Pink ZFF
• Fast Pink Y
• Helanthrene Pink R
• Ciba Pink FF
• Vat Pink FF
• Helindone Pink CN
• Amanthrene Pink FF

References_____________________________________________________________________

 (1) Weisz A, Perez-Gonzalez M, Wood JF, Ridge CD, Ito Y. Identification, separation by spiral high-speed counter-current chromatography, and quantification of 7-chloro-5-methyl-2H-1,4-benzothiazin-3(4H)-one, an impurity in the thioindigoid color additive D&C Red No. 30 and its lakes. J Chromatogr A. 2021 Jan 25;1637:461863. doi: 10.1016/j.chroma.2020.461863. 

Abstract. An impurity in the color additives D&C Red No. 30 (R30) and D&C Red No. 30 lakes (R30L) was newly identified and characterized as 7-chloro-5-methyl-2H-1,4-benzothiazin-3(4H)-one (BTZ), and its extent and level in certified batches of these color additives was determined. BTZ was extracted from the dye with ethanol, resulting in a crude extract enriched to a concentration of over 60%. BTZ was then separated from a portion of the enriched extract by high-speed counter-current chromatography using a spiral-tube assembly column with intermittently pressed tubing of 60 ml capacity. It was the first reported use of such a column to separate a small, moderately hydrophobic compound. The two-phase solvent system was also moderately hydrophobic, consisting of hexane-ethyl acetate-methanol-water (5:2:5:2), and the retention of the organic stationary phase measured after the separation was 83.3%. The separation yielded BTZ of two purity grades, the higher of which (~95.5%) was used as a standard to quantify the impurity in 37 batches of R30 and R30L using an HPLC method developed and validated for that purpose. Analyses revealed a wide range of BTZ levels across batches, <0.05 - 0.84%, and suggested that BTZ contamination could be reduced by appropriate adjustments in the manufacturing process. An explanation of the likely source of BTZ - as a side-reaction product in a particular step of the manufacturing process - was also presented.