112 PROCEEDINGS OF THE AMERICAN ACADEMY. 



IV. 



ON THE FORMATION OF VOLATILE COMPOUNDS OF 

 ARSENIC FROM ARSENICAL WALL PAPERS. 



By Charles Robert Sanger. 



Received November 9, 1893. 



In cases of chronic poisoning from arsenical wall papers, the form 

 in which the arsenic leaves the paper has been a long disputed ques- 

 tion. Certain well defined symptoms were easily attributable to the 

 local irritant action of arsenical dust in the form of arsenious oxide, 

 the copper greens, etc., and the extension of these symptoms to the 

 digestive organs could be referred to the same cause. Yet, on the 

 other hand, under conditions unfavorable to the separation of arseni- 

 cal dust, as, for instance, where an arsenical paper underlay one that 

 was perfectly free, cases of poisoning have been very frequent, and to 

 explain them the formation of a gaseous or volatile arsenical compound 

 was assumed. 



Experiments to decide this point have been numerous since chronic 

 arsenical poisoning by wall papers was recognized, but none of them 

 until recently have been decisive, as they were with few exceptions 

 carried on under unfavorable conditions and by methods that in point 

 of exactness left much to be desired. Each side has had its adherents, 

 the one asserting that chronic poisoning must be due entirely to dust, 

 the other declaring that the cause lay in the absorption of an arsenical 

 gas, or in the combined action of gas and dust. Many, not believing 

 that the absorption of dust could alone lead to the numerous extreme 

 or obscure cases that have been observed, have used the lack of proof 

 of gas formation as an argument against the possibility of chronic 

 poisoning from arsenical surroundings, although they admitted the 

 local action of dust in certain cases. Further, those who denied the 

 possibility of arsenical poisoning from wall paper under any circum- 

 stances considered their position strengthened by the failure to establish 

 definitely the formation of a gaseous compound. 



It was in this doubtful state that the question lay at the time when 

 this investigation was begun, some seven years ago. My work was 



