Sudan I

Structural formula
General
Surname	Sudan I
other names	Sudan Orange 220 Fat orange R01 1-phenylazo-2-naphthol CI 12055 CI Solvent Yellow 14
Molecular formula	C 16 H 12 N 2 O
Brief description	brown-orange to red powder
External identifiers / databases
CAS number 842-07-9 EC number 212-668-2 ECHA InfoCard 100,011,517 PubChem 5858445 Wikidata Q901018
properties
Molar mass	248.28 g mol −1
Physical state	firmly
Melting point	134 ° C
safety instructions
GHS hazard labeling from  Regulation (EC) No. 1272/2008 (CLP) , expanded if necessary Caution H and P phrases H: 317-341-351-413 P: 280
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Sudan I is a synthetically produced azo dye from the group of Sudan dyes .

presentation

Sudan I can be produced by azo coupling of diazotized aniline with 2-naphthol .

properties

Sudan I consists of β-naphthol with an arylazo group attached to the α-position of naphthol. Because it contains the functional group RN = NR ', it belongs to the azo compounds. It turns out that Sudan I suffers from oxidative photo-degradation through two different mechanisms, singlet oxygen degradation and the degradation of free radicals, which reduces the authenticity of the materials. This effect can be reduced by introducing radical quenching substituents.

metabolism

While the metabolism of Sudan I is not yet understood in humans, its metabolism in rabbits is known. There Sudan I is mainly metabolized by the liver through oxidative or reductive reactions.

Azo reduction from Sudan I produces aniline and 1-amino-2-naphtol, and this reaction appears to be responsible for the detox. In vivo, after oxidation of Sudan I, C-hydroxylated metabolites are formed as the main oxidation products and excreted in the urine. These metabolites are also found in vitro after oxidation with rat hepatic microsomes.

The C-hydroxylated metabolites can be regarded as detoxification products, while the microsome-catalyzed enzymatic splitting of the azo group of the benzinediazonium ion (BDI) formed from Sudan I reacts with the DNA in vitro. The major DNA adduct formed in this reaction was identified as 8- (phenylazo) guanine, which was also found in the liver DNA of rats exposed to Sudan I.

use

Sudan I, powder

Sudan I is used, among other things, for yellow Semtex dyeings. It is used industrially for coloring heating oil, shoe polishes, floor wax and for the production of writing colors.

In the European Union , the colors Sudan I to IV have not been approved as food additives since 1995 because they can be broken down in the body into amines , some of which are carcinogenic . Since the EU-wide controls introduced in mid-2003, Sudan dyes have been repeatedly detected in imported products. While the controls previously concentrated on chili powder , turmeric and native palm oil are now also being targeted. The substances can also be found in products containing tomatoes and paprika, such as pesto .

safety instructions

Sudan I can cause allergic skin reactions and irritation of the skin, which can occur in particular with textile workers or when wearing tight-fitting textiles that are dyed with this dye. Allergic reactions are induced when the azo dye binds to human serum albumin (HSA) and forms a dye-HSA conjugate, which causes the release of histamine . Sudan I is also believed to cause genetic defects. The mutagenicity and genetic risk were with the Ames test assessed and animal studies. In addition, there is a suspicion of carcinogenic effects.

Individual evidence

1. ↑ ^{a b c d} Entry on 1-phenylazo-2-naphthol in the GESTIS substance database of the IFA , accessed on November 8, 2016(JavaScript required) .
2. ↑ Entry on 1-phenylazo-2-naphthol in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on February 1, 2016. Manufacturers or distributors can expand the harmonized classification and labeling .
3. ↑ Synthesis of Sudan ‐ I
4. ↑ Clayden, JG, N. Warren, S. Wothers, P., Organic Chemistry 1st ed .; Oxford University Press: 2001.
5. ↑ Griffiths, J .; Hawkins, C., Synthesis and photochemical stability of 1-phenylazo-2-naphthol dyes containing insulated singlet oxygen quenching groups. Journal of Applied Chemistry and Biotechnology 1977, 27 (4), 558-564.
6. ↑ Childs, JJ; Clayson, DB, The metabolism of 1-phenylazo-2-naphthol in the rabbit. Biochemical Pharmacology 1966, 15 (9), 1247-1258.
7. ↑ Stiborova, M .; Asfaw, B .; Anzenbacher, P .; Hodek, P., A New Way To Carcinogenicity Of Azo Dyes - The Benzenediazonium Ion Formed From A Non-Aminoazo Dye, 1-Phenylazo-2-Hydroxynaphthalene (Sudan-I) By Microsomal-Enzymes Binds To Deoxyguanosine Residues Of DNA. Cancer Letters 1988, 40 (3), 327-333.
8. ↑ Stiborova, M .; Asfaw, B .; Frei, E., Peroxidase-Activated Carcinogenic Azo-Dye Sudan-I (Solvent Yellow-14) Binds To Guanosine In Transfer-Ribonucleic-Acid. General Physiology and Biophysics 1995, 14 (1), 39-49.
9. ^ Alexander Beveridge: Forensic Investigation of Explosions , CRC Press, 1998, ISBN 0-7484-0565-8 , p. 297 ( limited preview in Google book search).
10. ^ Landeslabor Berlin: Annual Report 2010 - Landeslabor Berlin-Brandenburg .
11. ↑ Federal Institute for Risk Assessment : Sudan I to IV dyes in food (PDF; 158 kB), BfR opinion of November 19, 2003.
12. ↑ lgl.bayern.de: Food: Sudan 1 in Spices and Spice Preparations - Results of the studies between July 2003 and December 2004 - Internet offer , accessed on November 10, 2016.
13. ↑ Hunger, K., Toxicology and toxicological testing of colorants. Review of Progress in Coloration and Related Topics 2005, 35 (1), 76-89.
14. ↑ Maronpot, R .; Boorman, G., Interpretation of rodent hepatocellular proliferative alterations and hepatocellular tumors in chemical safety assessment. Toxicologic Pathology 1982, 10 (2), 71-78.
15. ↑ Matsumura, S .; Ikeda, N .; Hamada, S .; Ohyama, W .; Wako, Y .; Kawasako, K .; Kasamatsu, T .; Nishiyama, N., Repeated-dose liver and gastrointestinal tract micronucleus assays with CI Solvent Yellow 14 (Sudan I) using young adult rats. Mutation research. Genetic toxicology and environmental mutagenesis 2015, 780-781 , 76-80.

Web links

Commons : Sudan Dyes  - Collection of Images, Videos, and Audio Files

• Colorants Sudan I to IV in food - Statement of the Federal Institute for Risk Assessment (BfR) of November 19, 2003

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