INDUSTRIAL FUMIGATION AGAINST INSECTS 47 



is necessary. If a fumigation chamber is used, the fumigants and 

 dosages recommended for the raw products can be used. If vacuum 

 fumigation is resorted to, excellent results can be obtained with a 

 dosage of 30 pounds of the ethylene oxide-carbon dioxide mixture per 

 1 ,000 cubic feet for a period of from 1 to 2 hours. 



Carbon disulphide blanketed with carbon dioxide is frequently used 

 for this purpose. Individual packages can be successfully treated in 

 the packing line with ethyl formate. From 5 to 9 cubic centimeters 

 of this material is spattered into the bottom of the paper or paper- 

 bag liner of 25-pound boxes of dried fruit. The fruit is then dropped 

 into the box, the liner folded over, and the cover nailed or pasted 

 down. 



INFESTATIONS IN WAREHOUSES 



Infestations that develop in storage warehouses can be handled by 

 fumigating the infested fruit in a fumigation chamber or vacuum 

 tank or by fumigating the entire storage section with hydrocyanic 

 acid. If the entire storage section is fumigated, a dosage of from 

 8 to 20 ounces of liquid hydrocyanic acid or its equivalent per 1,000 

 cubic feet of space should be used for a period of 24 hours. The 

 dosage will depend on the tightness of the storage section and the 

 quantity of fruit in storage. 5 



CURED MEATS AND CHEESES 



Infestation of cured meats and cheeses by mites, ham beetles, or 

 skippers frequently makes fumigation necessary. Meat-storage 

 houses that are reasonably tight can usually be successfully fumigated 

 with hydrocyanic acid at the rate of 1 pound of liquid hydrocyanic 

 acid or its equivalent per 1,000 cubic feet for a period of 24 hours. 

 Such treatment does not injure the meats, but if the infestation has 

 penetrated deeply into the meat, it is difficult to get a perfect kill. 

 The Federal meat-inspection regulations 6 require that permission for 

 each fumigation be obtained from the Federal meat inspector. 



Cheeses that are protected by an unbroken layer of paraffin can be 

 safely fumigated with hydrocyanic acid, but, owing to the danger of 

 their absorbing large quantities of the gas, unprotected cheeses should 

 be removed from a warehouse that is to be fumigated. 



For the treatment of small quantities of cured meats, or cheeses, a 

 fumigation vault or other tight container is recommended. Carbon 

 disulphide at the rate of 10 pounds, ethylene oxide at the rate of 2 

 pounds, or the ethylene oxide-carbon dioxide mixture at the rate of 

 20 pounds, per 1,000 cubic feet of space can be used for a period of 

 24 hours. 



STORED TOBACCO 7 



Tobacco that is held in storage (figs. 39 and 40) often becomes in- 

 fested with the cigarette beetle (Lasioderma serricorne Fab.) or the 

 tobacco moth (Ephestia eluteUa Hbn.). If the infested tobacco is 



5 Detailed information regarding the fumigation of dried fruit can be found in the 

 Bureau of Entomology and Plant Quarantine Mimeographed Circular E-353, Dried Fruit 

 Fumigation. 



fl U. S. Department of Agriculture, Bureau of Animal Industry, Service and Regulatory 

 Announcements, January 1921, p. 3, and August 1927, p. 62. 



7 More detailed information on the fumigation of tobacco warehouses will be found 

 in the Bureau of Entomology and Plant Quarantine Mimeographed Circular E-325, The 

 Fumigation of Tobacco Warehouses. 



