E142 is a chemical compound, synthetic green triphenylmethane dye (Triphenylmethane is a hydrocarbon), listed as a European food additive. It goes by the name CI 44090 or Green S in the Colour Index International, but has many synonyms.

Chemical name: sodium;4-[[4-(dimethylamino)phenyl]-(4-dimethylazaniumylidenecyclohexa-2,5-dien-1-ylidene)methyl]-3-hydroxynaphthalene-2,7-disulfonate

It appears in the form of a green powder

What it is used for and where

Cosmetics

Colorant. This ingredient has the primary function of colouring the solution in which it is inserted in a temporary, semi-permanent or permanent manner, either alone or in the presence of the complementary components added for colouring.

Food

E142 o Green S showed no adverse signs in studies at doses up to 500 mg per day in relation to body weight/day (1), but interesting activity against Plasmodium falciparum (Welch, 1897) the unicellular parasitic protozoan responsible for malaria (2).

Molecular Formula   C₂₇H₂₅N₂NaO₇S₂

CAS  3087-16-9

 EC number  221-409-2

UNII 9B7E8Y9D0X

DTXSID4046577

Synonyms:

• Wool Green S
• Calocid Green S
• Lissamine Green B
• Acilan Green BS
• Food Green S
• Vondacid Green S
• Acid Leather Green S
• Erio Green S
• Acid Brilliant Green BS

References_____________________________________________________________________

(1) Moorhouse SR, Creasy DM, Gaunt IF. Three-generation toxicity study of rats ingesting Green S in the diet. Food Chem Toxicol. 1987 Dec;25(12):985-93. doi: 10.1016/0278-6915(87)90293-6. 

Brantom PG, Creasy DM, Gaunt IF. Long-term toxicity study of Green S in mice. Food Chem Toxicol. 1987 Dec;25(12):977-83. doi: 10.1016/0278-6915(87)90292-4. 

(2) Leba LJ, Popovici J, Estevez Y, Pelleau S, Legrand E, Musset L, Duplais C. Antiplasmodial activities of dyes against Plasmodium falciparum asexual and sexual stages: Contrasted uptakes of triarylmethanes Brilliant green, Green S (E142), and Patent Blue V (E131) by erythrocytes. Int J Parasitol Drugs Drug Resist. 2017 Dec;7(3):314-320. doi: 10.1016/j.ijpddr.2017.07.002.