COAL-TAR COLORS USED IN FOOD PRODUCTS. 



On the following Buss is noncommittal: 



Auramin (425) 



Biebrich Scarlet (163) 



Water blue (480) 



Magenta (448) 



Aurin J (483) 



Acid Green (435) 



Wine Green (?) 



Milling Red (?) 



Azo-acid Blue (36) 



Fast rose... m 



Naphthol Black of various brands, which seemed to be mixtures. 



2. It has been pointed out that the following nine colors are harm- 

 less: 



Naphthol Yellow (4) 



Naphthol Brown (?) 



Chinolin Yellow (667) 



Pyrotin RRO (115) 



Acid Green (434, 435) 



Most of these have not been examined experimentally, but scien- 

 tific studies have been made of the poisonous qualities of Azo-Blue 

 and Naphthol Yellow. (Zts. angew. CJiemie, 1896, p. 24.) 



3. Chlopin in his monograph (see p. 75) says: 



On the basis of my personal experience I consider the testing of the action of coal- 

 tar dyes on man not permissible, since such experiments may induce in the subjects 

 of experiment more or less serious symptoms of poisoning, for which in some cases 

 there are no antidotes at our disposal. To such accidents, in my opinion, only the 

 experimenter himself may subject himself, because he knows what he is doing. Pre- 

 liminary tests of dyes on dogs and other animals afford no guaranty of escape from dis- 

 agreeable accidents which may take place in the testing of the dye on man. (Page 111 . ) 



These data and calculations convincingly prove how erroneous the current opinion 

 is that for the coloring of food substances and beverages only exceedingly small, 

 almost unweighable, quantities of dyes are used. (Page 113.) 



On page 221 et seq., the following general discussion of this subject 

 is found : 



THE MANNER OF ACTION OF POISONOUS DYES ON THE ANIMAL ORGANISM. 



The mechanism and the chemistry of the action of the artificial dyes of the aromatic 

 series on the animal organism remains to the present day, with few exceptions, 

 exceedingly slightly and superficially studied. The same can be said also concern- 

 ing the pathological and anatomical changes which are induced by these dyes. 



More than the others there have been studied in the toxicological respect the dyes 

 belonging to the Nitro group; Picric Acid; Martius Yellow (Dinitro-naphthol potas- 

 sium), and Saffron substitute (Dinitrocresol potassium.) 



According to Robert, these dyes belong to the poisons acting on the blood. Accord- 

 ing to the same authority, Methylene Blue, which belongs to the other chemical 

 group of Thiazins, acts similarly. 



In the fundamental works on the sanitary investigations for the dyes, by Cazeneuve 

 and Lepine, by Weyl, and by Santori, we find almost no material relating to the 

 explanation of the manner of the action of the dyes. These investigators limiting 

 themselves to a very cursory description of the symptoms o,f poisoning, and reciting 

 in most general terms the results of autopsy, not even indicating the cause of death. 

 Such, for instance, are the reports of autopsies made by T. Weyl and some other 

 investigators, as quoted above. 



1 Apparently a purified form of Corallin. 



