52 POWDERED VEGETABLE DRUGS 



insecticide which does not destroy or modify the active constituents 

 of the drug nor poison it. Bisulphide of carbon is perhaps the most 

 effective insecticide. It kills the larvae and mature insects, but does 

 not destroy the eggs ; hence several inspections are necessary after the 

 insecticide has been used, as the eggs may be present from which new 

 larvae develop. 



The bisulphide of carbon may be used as follows : Place the cleaned 

 drug loosely in the container or in a roomy, dry, clean box with tight 

 cover or lid. Pour some of the bisulphide of carbon in a flat vessel 

 and place it in the box containing the drug, close the box and leave the 

 drug exposed to the vapor of the insecticide for several hours or more, 

 the time of exposure depending upon the quantity of the drug. 



Pieces of gum camphor placed with the drug are said to drive 

 away insects; it does, however, not kill them. Boxes and containers 

 in which insect parasites have existed should be thoroughly washed 

 and scalded in boiling water to kill the eggs that may be present and 

 then thoroughly dried, before the drugs are replaced. 



Powdered drugs may be treated like crude drugs. Larvae and 

 insects may, however, be more readily removed by sifting; the eggs 

 will, of course, pass through the sieve with the powder; hence repeated 

 inspection and perhaps repeated sifting may be necessary. The 

 mature insects of powdered drugs usually work their way to the sides 

 of the glass bottles and other transparent containers where they can 

 be readily detected. The larvae remain in the interior of the powder. 



Chloroform and ether may be used like bisulphide of carbon, or it 

 may be sprinkled over the drug directly and the container closed. 

 These insecticides must, however, not be used too frequently or too 

 profusely, as they undoubtedly destroy some of the active constituents. 



In the majority of cases it is best to discard infested drugs, espe- 

 cially powders, as it is not possible to remove the insects completely 

 without much care and trouble. Furthermore, the presence of para- 

 sites in considerable numbers is an indication that the store-room, as 

 well as drug stock and containers, need a thorough overhauling and 

 cleaning, in order to make it suitable for the purpose of storing crude 

 and powdered drugs. It is difficult and practically impossible to 

 prevent the invasion of parasites in dirty, littered store rooms having 

 bad floors, walls and ceilings with large cracks, nail holes, nooks and 

 corners which are never cleaned, and where the atmosphere is moist 

 and where fresh air does not circulate, and to which sunlight has no 

 access. The opinion that "any old corner" will do as a store-room for 

 drugs is all too prevalent. The store-room should be dry, cool, well 

 lighted and well aerated and spacious. 



