UNITED STATES DEPARTMENT OF AGRICULTURE 
BULLETIN No. 568 
Joint Contribution from the Bureau of Plant Industry 
WM. A. TAYLOR, Chief, and the Bureau of 
Chemistry, CARL L. ALSBERG, Chief 
&Jff 
Washington, D. C. 
PROFESSIONAL PAPER 
August 8, 1917 
THE PRESENCE OF ARSENIC IN HOPS. 
By W. W. Stockberger, Physiologist in Charge of Drug-Plant and Poisonous-Plant 
Investigations, Bureau of Plant Industry, and W. D. Collins, Food- Investigation 
Chemist, Bureau of Chemistry. 
Situation with respect to arsenic in hops . 
Collection of materials for examination. . , 
Analysis of materials 
CONTENTS. 
Page. 
Results of analyses. 
Conclusions 
Pager, 
3 
7 
SITUATION WITH RESPECT TO ARSENIC IN HOPS. 
At times the detection of minute traces of arsenic in shipments of 
American hops exported to foreign countries has led to their rejection 
by prospective purchasers. The loss sustained in such cases is 
borne by the exporter; consequently American growers, who sell as a 
rule to local buyers only, do not realize fully the extent to which the 
salability of American hops on foreign markets may be affected 
unfavorably by an occasional contaminated shipment. 
The profitableness of hop production in the United States is deter- 
mined practically by the extent of the foreign demand for the crop 
surplus in excess of the requirements for domestic consumption. 
Any impairment of the quality of American hops, whether definitely 
proved or only suspected by foreign consumers, lessens the chances 
for marketing the surplus at reasonable prices and eventually reacts 
upon the grower in a lower price for his product. Although the 
probability of any damage to the public health from arsenic com- 
municated by hops to ale or beer seems very remote, nevertheless the 
minute quantity of arsenic permissible in hops under some foreign 
standards of purity lays the grower under obligation to use everjr 
reasonable precaution to avoid all possible sources of contamination.. 
In a bulletin published in 1908 by the Bureau of Plant Industry/ 
impure sulphur was suggested as the source of the traces of arsenic 
1 Stockberger, W. W. The sources of arsenic in certain samples of dried hops. In U. S. Dept. Agr.„ 
Bur. Plant Indus. Bui. 121, p. 41-46. 1908. 
101097°— Bull. 568—17 
