Carcinogenic azo dyes

Yahagi, T., Degawa, M., Seino, Y., Matsushima, T. and Okada, M. (1975). Mutagenicity of carcinogen azo dyes and their derivatives. Cancer Lett. 1 91-96. 

To protect human health and improve consumer safety, the European Parliament and the Council of the European Union (EU) pubhshed Directives 2002/61/EC and 2003/3/EC on September 11, 2002 and January 6, 2003, respectively. These restrict the use of carcinogenic azo-dyes in textiles and leather articles and prohibits the sale of such articles dyed with the restricted azo dyes. Directives 2002/61/EC and 2003/3/EC had been transposed into national laws and put into effect in the member states respectively by September 11,2003 and June 30,2004. Aromatic amines (azo dyes) (22 kinds) specified and prohibited by Directive 2002/ 61/EC are listed in Table 3.3. 

The EU Commission classified 22 amines as proven or suspected human carcinogens. Azo dyes which, by reductive cleavage of one or more azo groups, may release one or more of these aromatic amines in detectable concentrations, that is above 30 ppm in the finished articles or in the dyed parts thereof may not be used in textile and leather articles which may come into direct and prolonged contact with the human skin or oral cavity (European Commission, 2002). The EU Directive 2002/61/EC has banned the use of dangerous azo colorants, placing textiles and leather articles coloured with such substances on the market, and requested... 

It was used as an end component in a few azo-dyes, but this use has been discontinued because of its carcinogenic character. 

Chromium, (ri6-benzene)tricarbonyl-stereochemistry nomenclature, 1,131 Chromium complexes, 3,699-948 acetylacetone complex formation, 2,386 exchange reactions, 2,380 amidines, 2,276 bridging ligands, 2,198 chelating ligands, 2,203 anionic oxo halides, 3,944 applications, 6,1014 azo dyes, 6,41 biological effects, 3,947 carbamic acid, 2,450 paddlewheel structure, 2, 451 carboxylic acids, 2,438 trinuclear, 2, 441 carcinogenicity, 3, 947 corroles, 2, 874 crystal structures, 3, 702 cyanides, 3, 703 1,4-diaza-1,3-butadiene, 2,209 1,3-diketones... 

Ponceau 4R (E 124, Cl Food Red 7, Cochineal Red A, New Coccine) is a mono azo dye consisting essentially of trisodium d-2-hydroxy-l-(4-sulfonato-l-naphthy-lazo)-6,8-naphthalenedisulfonate. It is a reddish powder or granules, soluble in water, sparingly soluble in ethanol. The absorption maximum is 505 nm in water, E, = 430. It is a suspected carcinogen and cannot be used as a food colorant in the US and other countries. -"... 

One of the main concerns regarding azo dyes is related to the possibility of their reduction by azoreductases, with the formation of unsulfonated aromatic amines with potential carcinogenicity. 

Sulfonated azo dyes are widely used in different industries [16]. Some structure of sulfonated and unsulfonated azo dyes is shown in Fig. 1. These water-soluble azo dyes will enter the environment generally with wastewater discharge. Also, these sulfonated and unsulfonated azo dyes have a negative aesthetic effect on the wastewater, and some of these compounds and biodegraded products are also toxic, carcinogenic, and mutagenic [17]. There exists clear evidence that sulfonated azo dyes show decreased or no mutagenic effect compared to unsulfonated azo dyes... 

Hildenbrand S, Schmahl FW, Wodarz R et al (1999) Azo dyes and carcinogenic aromatic amines in cell culture. Int Arch Occup Environ Health 72 M52... 

The use in consumer products of azo dyes that yield carcinogenic amines under reductive conditions is illegal in Germany. Detection of such carcinogenic amines in textiles is problematic, and a method was proposed combining TLC, automatic multiple development... 

Azo dyes, used in textiles, leather, printing, paper making, drugs and food industry Mutagenic and carcinogenic... 

The carcinogenic aromatic amines released from azo dyes in leather were investigated by using microwave-assisted extraction (MAE) or supercritical fluid extraction (SFE) followed by RP-HPLC. The chemical structures of dyes and aromatic amines are listed in Fig. 3.69. The flow schemes for SFE and MAE are shown in Figs 3.70. and 3.71. 

S. Borros, G. Barbera, J. Biada and N. Agullo, The use of capillary electrophoresis to study the formation of carcinogenic aryl amines in azo dyes. Dyes Pigm., 43 (1999) 189-196. 

Bowman MC, Rushing CR. 1981. Trace-level determination of benzidine, 3,3 -dichlorobenzidine in animal chow wastewater and human urine. In Egan H, ed. Environmental carcinogens - selected methods of analysis. Volmne 4. Some aromatic amines and azo dyes in the general and industrial environment. Lyon, France International Agency for Research on Cancer, 159-174. 

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