364 



JOURNAL OF ECONOMIC ENTOMOLOGY 



[Vol. 9 



DETECTION OF ARSENIC IN BEES^ 



By E. B. Holland 



The high periodical mortality in numerous apiaries of the state during 

 the past few years has led to the examination in the Station laboratory 

 of many samples of bees and of comb submitted by the Station apiarist. 

 As a rule, little information was obtainable except that a large per- 

 centage of a colony or colonies had died within two or three days. 

 Disease was not considered the cause of death as no disease of the 

 adult bee has as yet been recognized. On the other hand, the old 

 theory of poisoning, so often advanced as a solution of like problems, 

 appeared more plausible than usual in view of the fact that spraying 

 with arsenate of lead or with Paris green has become the general 

 practice of farmers, horticulturists and tree wardens for protection 

 against leaf-eating insects. Furthermore, bees obtain pollen and 

 nectar from a large number of "honey" plants over an area of ap- 

 proximately a dozen square miles (two mile radius) ^ and are very 

 active during the spraying season. Bees, therefore, must be par- 

 ticularly liable to injury if arsenical or other "stomach poison" 

 insecticides are used in the vicinity. The above assumption was 

 substantiated in a large measure by chemical examination. A small 

 amount of arsenic was found in 12 samples out of 23 submitted, as 

 shown by the following table. The detection of arsenic in stored 

 pollen was of special interest. 



At least 10 grams of material are deemed necessary for satisfactory 

 work. Considerable labor is involved, however, in collecting that 

 number of bees free from dirt and litter. As the arnounts employed 

 varied from 40 grams to less than 2, the tests are not strictly com- 

 parable. Moreover, the percentage of reacting samples was sub- 

 stantially reduced by including several lots secured in the course of 

 the work that were not even suspected of poisoning. 



1 Published with the approval of the Director of the Massachusetts Agricultural 

 Experiment Station. 



^ According to J. L. Bj'ard, superintendent of the College apiary. 



