INVESTIGATIONS ON HARMFULNESS. 51 



tellable information on this subject can be gained only by physiological experiment, 

 8 we can not say definitely whether a substance, color or any other, is injurious or 

 ,ot without finding out for every substance by experiment. This has been done for a 

 onsiclerable number of aniline colors, and these experiments are the only things that 

 eserve any attention. Everything else is idle talk. * * * There are a very 

 irge number of aniline colors that have not been treated yet, and we are safe in saying 

 lat among these will be also some harmless and others injurious. As they have not 

 een experimentally tested, we do not know which are harmless and which are not; 

 t will therefore be clear that a law forbidding the indiscriminate use of aniline color 

 >r the purpose of coloring articles of food is necessary and useful. 

 But if the meaning of the law is to prevent only the use of injurious colors, as it 

 ppears to be, then the way to proceed would be very definitely outlined. Besides 

 hysiological colors, all such colors should be forbidden that have been found to be 

 ijurious and such aniline colors as have not been tested sufficiently. There will 

 len be left over a number of aniline colors which have been proven by experiment 

 D be entirely harmless, even if taken in large doses. 



The experimenters were quite impartial. They had no preconceived ideas, but 

 tarted simply to find out the true state of affairs. Their reports are therefore very 

 liable, and it will not do to overlook or to ignore them. The colors that they found 

 armless can be considered perfectly safe, so much the more as the doses conveniently 

 ken with food would be much smaller than the doses that have proven to be harm- 

 ss. These harmless aniline colors carry all the shades wanted in the food industry, 

 'he law should provide that one of these colors (or mixtures of these) must be used 

 hen a food article is being colored, because these few aniline colors are the only 

 olors that can be considered perfectly safe as far as our present knowledge goes, 

 bthing should be left to guesswork or experimenting, as is the case just now. The 

 olors that are permitted should be enumerated by their scientific as well as by their 

 ommercial names, and only such colors should be listed as permissible for coloring 

 ood products as have been proven to be harmless, even in large doses. Provision 

 hould be made to insure the purity of the colors sold for coloring food; the manner 

 f packing such colors and the labeling of same should be laid down clearly, and all 

 olors now listed, aniline as well as physiological colors, should be strictly forbidden. 

 E the problem is viewed without preoccupation and prejudice, the facts given above 

 speak for themselves. 



nil. INVESTIGATIONS, OTHER THAN ON ANIMALS, BEARING ON 

 THE HARMFULNESS OF COAL-TAR COLORS. 



PFEFFEB. 



Pfeffer, writing on the Absorption of Anilin Colors by Living 

 }ells, summarizes his results as follows: 



The relatively little poisonous Methylene Blue does damage protoplasm in a solution 

 f 0.001 per cent. 



Methyl Violet: This coloring matter is not only stored up in the juices of the cell, 

 ut is also able to color the living protoplasm, and care is necessary, on account of the 

 oisonous nature of the Methyl Violet, to prevent damage; these cautions are based 

 pon solutions of 0.0003 to 0.00001 per cent strength. 



Methyl Violet less poisonous than Cyanin. 



Bismarck Brown about as poisonous as Methylene Blue. 



Fuchsin as poisonous as Methylene Blue. 



Safranin as poisonous as Methylene Blue. 



Methyl Orange is poisonous only to a slight degree. 



Tropseolin 000, Tropseolin 00, and Rosolic Acid are not poisonous. 



