March 14, 1913] 



SCIENCE 



401 



regular experimentation two of the men in 

 my group who had followed the regular 

 routine continued for seven days longer, 

 with higher dosage. They began with 5 

 grams a day and finished with 10 grams, 

 the average being 7.5 grams daily. With 

 this large dosage there was no reduction 

 which could be noticed with Pehling solu- 

 tion, and nothing which was outside the 

 normal limits for the ammoniacal solution, 

 although there appeared to be a slight in- 

 crease from the former figures. Other 

 changes were absent. A third man who 

 had not been a member of the experimental 

 squad, but who had followed the same diet 

 routine, took doses beginning with 5 grams 

 and ending with 7.5 grams on the seventh 

 day. No abnormal behavior of any de- 

 scription was noted in his excretion or 

 general condition. In this case it could 

 not be urged that the man had become 

 accustomed to large doses through gradu- 

 ally increasing small doses. 



Temperature, Pulse, Respiration. — All 

 these factors were systematically noted 

 from day to day for each man. Absolutely 

 no variations from the normal were ob- 

 served which might in any way be at- 

 tributed to or connected with the dosage 

 of benzoate. 



Conclusions. — From all these observa- 

 tions the conclusion was drawn that in the 

 dosage administered, which is large enough 

 for practical purposes, sodium benzoate 

 exercises no recognizable physiological ac- 

 tion on the human organism, beyond the 

 slight increase in hippuric acid excretion, 

 a change which is often exceeded after 

 hearty meals of certain berries and fruits 

 which are frequently consumed in quan- 

 tity. I have recited the facts in some 

 detail because of the long-continued and 

 persistent attempts to create the impres- 

 sion, especially in this country, that sodium 



benzoate exerts a toxic action, sufficiently 

 marked to warrant its exclusion from use 

 with foods. 



Gerlach's Studies. — Attention must be 

 called here to an elaborate investigation 

 carried out by Dr. Gerlach, of Wiesbaden, 

 on the efi'ects of sodium benzoate as used 

 in the food industries. These experiments 

 were continued through a long period and 

 appear to have been conducted with great 

 care. From the numerous clinical and 

 metabolism observations made Dr. Gerlach 

 draws the conclusion that sodium benzoate 

 causes no changes in the body which may 

 be considered as harmful, or which may be 

 taken as pointing to departure from the 

 normal in any direction.^** 



COPPER SALTS 



It has long been a popular notion that 

 copper salts are decidedly toxic and the 

 older medical literature contains many ref- 

 erences to poisoning by verdigris and other 

 combinations of copper. Modern study, 

 however, has shown that these assumed 

 effects were greatly exaggerated. The 

 subject has practical interest now because 

 of the custom, which had its origin in 

 Prance, apparently, of fixing the color of 

 certain green vegetables by cooking them 

 in the canning process in contact with 

 small amounts of copper sulphate, or other 

 copper salt. The effect depends on the 

 formation of a very stable green compound 

 of copper and a derivative of chlorophyll. 



The permissibility of the process has 

 been much debated, especially in France, 

 Germany and Belgium. In France the 

 discussion has been a prolonged one and 

 several scientific commissions have taken 

 part in it. Some of the older commissions 

 made reports finding against the use of 



" Dr. med. V. Gerlach, ' ' Physiologisehe Wirk- 

 ungen der Benzoesaeure und des benzoesauren 

 Natron," Wiesbaden, 1909. 



