ABSORPTION OF HYDROCYANIC ACID BY FOODS 
an hour after the fumigation was completed. Most of the samples 
were then divided, one part being held at room temperature (about 
70° F.) and the other in cold storage (about 40° F.). Hydrocyanic 
acid determinations were made on them at the end of 1, 7, 30, and 90 
days. The results of these tests are shown in Table 2. 
All of the dried fruits left unwrapped during fumigation absorbed 
hydrocyanic acid. Because of the wrappings, those fumigated in 
packages absorbed less — sometimes none. The box of dried apples 
was loosely packed and was lined with ordinary newsprint paper which 
permitted the gas to pass into the dried apples ; in fact, it penetrated 
so well that the concentration in the center of the box was nearly as 
high as that in the outside layers. On the other hand, the box of 
apricots was tightly packed and was enclosed in waxed paper. No 
hydrocyanic acid was present in the packed apricots. The pasteboard 
carton of raisins gave little protection from the fumigant. The 
waxed paper tightly wrapped around the seeded raisins, however, 
was a very good protection. The figs in the 20-pound box were 
tightly packed. While a little hydrocyanic acid penetrated through 
the outer wrapping into the outer layer, of fruit, none was found in the 
center of the box. Of course, such fumigation will not kill insects 
inside the box; in fact, live worms were found in the center of the box 
of figs. 
Most of the fruits contained some hydrocyanic acid at the end of 
three months. They lost it more quickly when kept at room tem- 
perature than when kept in cold storage. The high original absorp- 
tion by the black raspberries and the tenacity with which they 
retained the hydrocyanic acid are worthy of note. No explanation of 
this action is offered. Fumigation caused no physical deterioration 
or impairment of keeping qualities in the fruit. 
Careful tests showed that no hydrocyanic acid was present in any 
of the fruit before fumigation. 
Table 3. — Hydrocyanic acid in fumigated candies, nut meats, chocolate, and cocoa 
Tempera- 
ture of 
fumigation 
Hydrocyanic acid present (parts per million) 
Troduct and condition for 
fumigation 
Begin- 
ning 
End 
Ini- 
tial 
Stored at about 70° F. 
for— 
Stored at about 40° F. 
for— 
1 
day 
7 
days 
30 
days 
90 
days 
1 ! 7 
day J days 
30 
days 
90 
days 
°F. 
79 
°F. 
72 
Chocolate creams, fumigated 
11 
22 
11 
18 
180 
200 
7 
9 
9 
3 

Coated nut meats, fumigated 
Chocolate creams in 1-pound 
3 
1 
Coated nut meats in 1-pound 
box _ 
Pecans, meats, fumigated loose .. 
English walnuts, meats, fumi- 
gated loose.- 
70 
70 
82 
66 
66 
76 
11 
11 
3 
5 
1 
4 

2 
11 
9 
7 
8 
3 
3 
Unopened, half-pound can of 

192 

15 
Half-pound can of cocoa, lid 
110 
44 
31 
Unopened, half-pound pack- 
Half-pound package of 
chocolate, fumigated 
11 
7 
4 
