New Safe Insecticides HERMAN WACHS, Dodge & Olcott, Inc., Bayonne, N. J., HOWARD A. JONES, U. S. Industrial Chemicals, Inc., Baltimore, Md., and LAWRENCE W. BASS, U. S. Industrial Chemicals, Inc., New York, Ν. Y.
Downloaded by PURDUE UNIV on June 27, 2016 | http://pubs.acs.org Publication Date: January 1, 1950 | doi: 10.1021/ba-1950-0001.ch011
In the search for safe insecticides, hundreds of products have been prepared and subjected to screening tests against insects. This paper presents information on six materials related to piperonyl butoxide, tested in combination with pyrethrins.
W o r l d food shortages lend added weight to the importance of safe insecticides. M o r e than 5 % of all cereal food is destroyed i n storage b y insects. The millions of tons lost each year are equal roughly to the volume of grains i n international trade. Protection of stored grains is only one aspect of the use of insecticides i n food conservation. Control of insects on growing crops, on livestock, i n food processing plants, i n storage, and i n the household assumes new significance i n view of the necessity for more adequate production of food stuffs. Insecticides that combine high efficiency against insects with complete safety to man and other warm-blooded animals are therefore a mighty weapon to ensure food supplies for the world. During World W a r I I popular interest i n insecticides was centered on the spectacular usefulness of D D T i n combating abnormal exposure of troops and civilian populations to insect pests. This important and versatile material has become almost a household synonym for "insecticide." N o w that we are engaged i n a war against hunger, however, public health authorities are becoming increasingly conscious of the fact that the protection of food products properly demands a high degree of safety i n any insecticides that are used for this purpose, a property that most of the existing commercial synthetic products do not possess. The ideal insecticide should meet the following exacting list of requirements : Toxicity to undesirable insects and lack of toxicity under conditions of use to desir able insects Complete safety for man and other warm-blooded animals R a p i d knockdown action toward insects with minimum recovery Stability on storage and exposure Solubility i n suitable solvents Freedom from irritation, undesirable odor, color, and staining properties Volatility low enough to ensure effectiveness over an adequate period of time Cost i n economic range I n the search for safe insecticides the authors have prepared hundreds of new prod ucts and subjected them to preliminary screening tests against insects. T h a t part of their work dealing with methylenedioxyphenyl derivatives was prompted b y the original fun damental studies of 0 . F . Hedenburg, with whom they have collaborated i n this field. T w o materials of this type—piperonyl butoxide (I) and piperonyl cyclonene (II)—have re cently been introduced commercially. These products have definite insecticidal properties in themselves, but show their maximum efficiency toward insects and other arthropods when used i n combination with pyrethrins. Furthermore, they are at least as nontoxic 43
AGRICULTURAL CONTROL CHEMICALS Advances in Chemistry; American Chemical Society: Washington, DC, 1950.
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ADVANCES IN CHEMISTRY SERIES
toward warm-blooded animals as pyrethrum, which is recognized as the safest insecticide in common use.
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