OIL-SOLUBLE OR FAT COLORS. 159 



ing and swollen kidney is harmless. On the other hand, a dye (572) 

 which produces no change or symptom observable during life, but 

 fatty degeneration of the liver is shown at the autopsy, is a harmful 

 dye. This lack of conformity makes the relation between dosage, 

 symptoms, and harmfulness or harmlessness more confusing and per- 

 plexing. 



YOUNG'S RULE. 



It must be remembered that smaller amounts of drugs, and, there- 

 fore, of coal tar colors, effect children as a rule than are effective 

 upon adults. Taking Young's rule as a guide, it appears that gen- 

 erally the effective dose for a 3-year-old child is one-fifth the effec- 

 tive adult dose; for a 4-year-old child one-fourth; for a 6-year-old 

 child one-third; for an 8-year-old child two-fifths and for a 12-year- 

 old child one-half the effective adult dose. All of this should be taken 

 into account in drawing conclusions from experiments as to the harm- 

 lessness of any coal-tar dye upon humans. Very little attention has, 

 however, been paid to this aspect of the matter in spite of the fact 

 that colored foods, confectionery, pastry, beverages, and the like are 

 partaken of by children and in many cases such articles are prepared 

 for the sole or particular consumption of the very young. 



From the foregoing data it seems clear that deductions as to the 

 harmlessness or harmfulness of coal-tar dyes when administered to 

 dogs, and not based upon autopsies, are not final nor conclusive as to 

 the effect upon the dog. The extent to which such deductions are 

 correctly transferable to humans is likewise not established. 



XI. OIL-SOLUBLE OR FAT COLORS. 



Oil-soluble colors are used for coloring fats, such as butter, oleo- 

 margarine, edible oils, and the like; of the coal-tar colors the oil- 

 soluble colors are chemically nonsulphonated azo-colors. 



The nonsulphonated azo-colors which have been physiologically 

 examined are: 



11. Sudan I (anilinazo-b-naphthol) (2). 



16. Butter Yellow (anilin-azo-dimethylanilin). 



17. Chrysoidin Y (anilin-azo-m-phenylene-diamin) (2). 



18. Chrysoidin R (anilinazo-m-tolylene-diamin) (1). 

 41. Chrysoidin R (o-toluidin-azo-m-tolylene-diamin). 



197. Bismarck Brown (m-phenylene-diamin-disazo-m-phenylene-diamin) (4). 

 201. Manchester Brown (m-tolylene-diamin-disazo-m-tolylene-diamin) (2). 



The numbers preceding the trade names are the Green Table num- 

 bers ; the scientific names appear in parentheses ; and the number of 

 dealers offering the colors on the United States market in the summer 

 of 1907, out of a possible 12, appear after the scientific name, also in 

 parentheses. 



