58 COAL-TAB COLORS USED IN FOOD PRODUCTS. 



4. The amount of coloring matter which has been determined quantitatively i 

 bonbons and liqueurs is so small that even the ones regarded as poisonous would ncl 

 be able to develop their harmful effects. (Zts. Nahrs. Unters. Hygiene Waarenk 

 1898, v. 7, p. 338.) 



8. Georgievics (Lehrbuch der FarbencJiemie, Leipzig, 1895 p. 10] 

 says under " Poisonous nature of the coloring matters:" 



It is a little known fact that of the very large number of organic coloring mattei 

 only a few have been found to be poisonous; these are Picric Acid, Victoria Orang 

 (Saffron-surrogate), Aurantia, Metanil Yellow, Orange II, and Safranin. The preju- 

 dice which is still quite widely accepted that most of the artificial coloring mattei 

 are poisonous dates from the early periods of anilin-color manufacture, at which tim 

 magenta and the coloring matters made from it occurred in commerce highly cor 

 taminated with arsenic. At present, however, these coloring matters are prepare* 

 absolutely free from arsenic, and are, as such, nonpoisonous. A few coloring mat 

 ters which occur commercially as zinc chlorid double salts, such as Methylene Blu 

 and Malachite Green, may be harmful in consequence of their zinc content, am 

 should therefore never be employed in the coloring of food products. * * * 

 consequence of their physiological activity some coloring matters are employed 

 medicines, indeed principally Methyl Violet, Auramin and Methylene Blue. Th 

 first two, known as blue and yellow Pyoctanin (pus-destroying) are, owing to thei 

 great antiseptic action and diffusibility, valuable medicines; on account of th 

 unpleasant coloring effect accompanying them they are but little used. Me thy 

 Violet was first recommended as an antibacterial remedy in diseases of the eye 

 Stilling; subsequently it has been employed in other special cases; its principa 

 use, however, is in surgery for the prevention of malignant proud flesh. 



The use of Auramin is entirely analogous. 



Methylene Blue (as a free base) is used principally as an analgesic (pain-relievinj 

 remedy) and is given internally; on account of its ability rapidly to diffuse throug] 

 the tissues of the nervous system; it can also be introduced by injection. It is use< 

 as a remedy against malaria, carcinoma, B right's disease, etc. 



The following have been tested as remedies or as antiseptics: Safranin, Lydii 

 (Mauvein), Vesuvin, Anilin Blue, Carbolic Magenta, Alizarin Yellow C (Gallaceto 

 phenone) , etc. The potassium salt of Dinitro-ortho-cresol was brought into com- 

 merce by the Farbenfabriken vorm. Friedr. Bayer & Co., under the name of Anti 

 nonnin, and has given excellent results as a means against formation of mold ir 

 cellars and against wood fungi. 



9. Weyl (Handbuch der Hygiene, 1896, p. 378) says: 



A few organic coloring matters, but only a very few, possess poisonous properties 

 A rule by means of which the poisonous or nonpoisonous nature of organic colorinj 

 materials can be determined without experiment is unknown even for those colorinj 

 matters whose constitution has been determined and experiments on the poisonous 

 nature of organic coloring matters are very few in number. 



10. Lewin (Lehrbuch der Toxicologie, 1897, p. 230) says: 



In the use of various fabrics or of foodstuffs, which are colored with anilin o 

 coal-tar colors, or in commercial contact with such colors, local and general symptom 

 of poisoning, such as eczema, swelling of the face, vomiting, diarrhea, anaesthesia 

 paresis, etc., have been observed. These are generally due to the toxic nature o 

 the coloring matters, frequently to harmful ingredients of the same, and hardly ever 

 to poisonous mordants. Many workmen in anilin factories show permanent spots 

 for example, on the cornea and conjunctiva, head, chest, face, and neck, withou 



