﻿12 BULLETIN 1149, U. S. DEPARTMENT OF AGRICULTURE. 



Table 5. — Hydrocyanic acid (parts per million) in fumigated field corn. 





Number 







Hydrocyanic acid after 









Sodium 

 cyanide. 



of times 

 chamber 

 was evac- 

 uated. 



Oday. 













1 day. 



4 days. 



7 days. 



14 days. 



30 days. 



60 days. 



90 days. 



Oz. per 





















100cu.fl. 



















1 



1 



1 



1 



2 





 1 

 2 

 3 









7.5 

 4.2 

 1.2 



2.5 

 2.1 

 1.2 



.8 



1.7 



1.2 None. 

 .8 None. 

 . 8 None. 

 .8 None. 



1.7 1.2 

































62 



5.8 



1.2 



0.8 



0.8 



2 



1 



25 



8.3 



3.3 1.7 1.2 



1.2 



1.2 



.4 



2 



2 



12 



5.0 



2.5 1 1.7 1.7 



1.7 



1.2 



.8 



2 



3 



8 



5.0 



2.5 1.7 1.7 



1.2 



1.2 



.4 



4 







42 



6.6 



3.3 3.3 2.5 



1.7 



1.2 



1.2 



4 



1 



25 



10 



3.3 3.3 2.9 



2.9 



2.1 



1.7 i 



4 



2 



25 



8.3 



4.2 I 3.3 2.1 



1.7 



1.7 



1.7 | 



4 



3 



17 



6.6 



3.3 I 2.5 2.5 



2.1 



2.1 



1.7 



6 







33 



5.0 



4.2 3.3 3.3 



2.1 



2.1 



1.7 



6 



1 



33 



10 



6.6 



5.8 5.8 



5.8 



5.0 



4.2 



6 



2 



33 



6.6 



5.0 



5.0 5.0 



3.3 



3.3 



3.3 





3 



33 



12 



6.6 



6.6 5-S 



4.2 



3.7 



3.3 



Table 6. — Hydrocyanic acid (parts per million) in fumigated cowpeas. 





Number 







Hydrocyani 



; acid after 









Sodium 

 cyanide. 



of times 

 chamber 

 was evac- 

 uated. 

















day. 



1 day. 



4 days. 



7 days. 



14 days. | 



30 days. 



60 days. 



90 days. 



Oz. per 





















lOOcu.ft. 





















1 



1 



1 



1 



2 





 1 

 2 

 3 









6.2 

 16 

 4.2 



4.2 

 5.0 

 4.2 



4.2 



3.3 



3.3 

 4.2 

 4.2 

 4.2 



2.5 



2.5 

 2.5 ; 

 2.5 ! 

 1.7 



2.1 



1.7 



2.1 

 1.7 

 1.2 



1.7 



12 



1.7 



.8 



.8 



1.7 



1.2 



1.7 



.8 



1.2 



1.7 









56 



16 



2 



1 



33 



16 



5.0 



3.3 



2.5 



2.1 



2.1 



1.7 



2 



2 



21 



17 



5.0 



4.2 



2.5 ! 



2.1 



1.7 



1.7 



2 



3 



16 



11 



4.2 



33 



3.3 



2.1 



2.1 



1.7 



4 







83 



33 



17 



6.6 



5-8 



5.8 



3.3 



2.1 



4 



1 



50 



33 



13 



5.0 



5.0 



5.0 



4.2 



33 1 



4 



2 



42 



33 



8.3 



5.0 



4.2 i 



4.2 



4.2 



3.3 



•i 



3 



42 



23 



6.6 



5.8 



5.8 



5.0 



3.3 



3.3 



6 







33 



17 



8.3 



8.3 



6.6 ' 



4.2 



4.2 



3.3 



6 



1 



83 



27 



8.3 



8.3 



7.5 



7.5 



6.6 



5.0 1 



6 



2 



130 



27 



17 



13 



5.0 



5.0 



5.0 



4.2 1 



6 



3 



100 



- 40 



13 



12 



. 



6.6 



6.6 



5.0 



No hydrocyanic acid was found in unfumigated samples of any of 

 the products, showing that none of it was naturally present in them. 



All of the seeds absorbed hydrocyanic acid on fumigation. The 

 results obtained on the day of fumigation have little comparative 

 significance, since much of the gas was loosely held and variations of 

 three or four hours in the times of standing were unavoidable. They 

 show, however, that the quantity then present is fairly large. Most 

 of it disappears during the first few days. In fact, in most cases the 

 hydrocyanic acid content, on the fourth day, was not more than 5 

 parts per million. After this time there was an extremely slow dis- 



