RECOMMENDATIONS BY ASSOCIATIONS, ETC. 43 



The results of our experiments have led us to the following conclusions: 



1. The relative nonpoisonous nature of the azo colors used for coloring wines explains 

 why this artificial coloring has not caused any real epidemic. 



2. This artificial coloring of wines by coal-tar colors is dangerous. It opens the door 

 to the employment of coloring matters of very variable and noxious properties. Thus 

 Martius Yellow, which is poisonous, has been used for 10 years past to color pastry 

 (3 grams per 100 kilograms) and it may be used to-morrow, perhaps, to color wines mixed 

 with a red or a blue. 



3. A rigid law against the artificial coloring of wines ought to be promulgated, 

 particularly if this coloration covers detestable practices most prejudicial to the public 

 health. The addition of salicylic acid, glycerin, and tartaric acid, or the acidifying 

 by sulphuric acid, is cloaked by the use of the coloring matter. 



Some sulphonated azo-coloring matters are sufficiently inert to enable their being 

 employed as artificial color in foods, bonbons, and liquors. These colors are manu- 

 factured according to simple processes which give theoretical yields and no metallic 

 sail , such as mercury, tin, or arsenic participates; sulphate of soda is the only impurity. 



In view of the great extent of the use of these coloring matters, it is better to regulate 

 their consumption by tolerating certain of these products rather than to interpose an 

 illusory barrier to their use. Where you can not arrest a stream you can at least regu- 

 late its course. 



It would be better definitely to classify these substances with respect to their noxious 

 properties, tolerate some and prohibit the others, rather than to be exposed to the 

 consequences of permitting manufacturers to introduce into food, without any scien- 

 tific control whatever, any products whatever. 



These coloring matters should be sold in commerce under the names of harmless 

 colors as determined by analysis. By chemical analysis it would be recognized as to 

 whether we were dealing with one color or with a mixture of two or three colors. 



The colors most used are made up of red, yellow, and blue, which apparently imitate 

 the appearance of the wines of the Midi. Thus we have recognized such coloring 

 matters in Roccellin, Naphthol Yellow, and Methylene Blue. 



Sulphonated Fuchsin is very much used, combined with a yellow and a blue. This 

 mixture turns green with ammonia, like the coloring matter of wine. In fact, Acid 

 Fuchsin is decolorized by ammonia. The yellow and blue remain intact, and give a 

 green which suggests true wine color. 



SOCIETY OF SWISS ANALYTICAL CHEMISTS. 



In 1891 the Society of Swiss Analytical Chemists recommended 

 that certain coloring matters which are to be regarded as harmful 

 to health should not be permitted to be used in the preparation of 

 articles of food intended for sale in which artificial coloring is at all 

 permitted. 



The coal-tar colors thus prohibited are identified in the following 

 by their Green Table numbers, only one trade name being given: 

 Picric A,cid (1); Dinitrocresol (2); Martius Yellow (3); Aurantia (6); 

 Orange II (86); Metanil Yellow (95); Safranin (584); Methylene 

 Blue (650). (Zts. Nahr. Unters. Hygiene, 1891, v. 5, p. 293.) 



TSCHIBCH. 



In 1893 Tschirch recommended as follows: 



1. The coal-tar colors, and in a narrow sense the anilin colors, are no longer harmful 

 on account of their arsenic content, since at the present time the great majority of 

 them are prepared free from arsenic. 



2. Some colors have shown themselves to be harmful to the system. 



