US3492405A - Insect chemosterilant methods employing phosphates - Google Patents

Description

United States Patent 3,492,405 INSECT CHEMOSTERILANT METHODS EMPLOYING PHOSPHATES Philip C. Hamm, Glendale, Mo.,- assignor to Monsanto Company, St. Louis, Mo., a corporation of Delaware No Drawing. Filed Mar. 30, 1967, Ser. No. 626,985

Int. Cl. A01n 9/36 US. Cl. 424-224 7 Claims ABSTRACT OF THE DISCLOSURE This invention relates to chemosterilant compositions and to methods for the control or eradication of insect populations. 1

The term insect" is used herein in its broad common usage to include spiders, mites, ticks and like pests which are not in the strict biological sense classified as insects. Thus, the usage herein conforms to the definitions provided by Congres in Public Law 104, the Federal Insecticide, Fungicide, and Rodenticide Act of 1947, Section 2, subsection b, wherein the term insect is used to refer not only to those small invertebrate animals belonging mostly to the class Insecta, comprising six-legged usually winged forms, as beetles, bugs, bee, flies, and so forth, but also to other allied classes of arthropods whose member are Wingless and usually have more than six legs, as spiders, mites, ticks, centipedes, and wood lice.

In accordance with this invention is has been found that insects can be controlled or eradicated by a method which comprises exposing the insect to amount of a compound of the formula wherein R and R are haloalkyl of not more than 4 carbon atoms and 3 halogen atoms (Cl, Br, F and I), and R is alkyl of not more than 18 carbon atoms.

In the above formula R and R can be haloalkyl, for example, chloromethyl, iodomethyl, bromomethyl, fluoromethyl, chloroethyl, iodoethyl, bromoethyl, fluoroethyl, dichloroethyl, diiodoethyl, dibromoethyl, difluoroethyl, chloro-n-propyl, bromo-n-propyl, iodoisopropyl, bromon-butyl, bromo-tert-butyl, 1,3,3 -trichlorobutyl, 1,3,3- tribromobutyl and the various homologues and isomers of haloalkyl of not more than 4 carbon atoms and 3 halogen atoms. In the above formula R is alkyl such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, amyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl and the various homologues and isomers of alkyl of not more than 18 carbon atoms. Compounds of the above formula wherein R and R are of not more than 2 carbon atoms and 3 chlorine atoms, and R is of not more than 12 carbon atoms are preferred.

For the sake of brevity, the compounds of the above formula which are useful in the compositions and methods of this invention are referred to hereinafter as chemosterilants.

In carrying out the methods of this invention, the

a sterilizing 3,492,405 Patented Jan. 27, 1970 chemosterilants, admixtures thereof or compositions containing them are applied to the insects or to their environment in an amount sufficient to exert a sterilizing action. The chemosterilant compositions of this invention generally contain from about 0.001% to about 99.99% by weight of chemosterilant. The lower concentrations of chemosterilant are particularly effective when the compositions are liquid, but it is preferred to use higher concentrations of chemosterilant when the compositions are semi-solid or solid. Compositions comprising from about 0.001% to :about 5% by weight of chemosterilant are preferred with those comprising from about 0.001% to about 2% by weight being particularly advantageous. A wide variety of insects, for example, house flies (Musca domestica), screw-worm flies (C0- chli'omyia hominivorax), Mexican fruit flies (Anastrepha ludens), oriental fruit fly, vinegar flies, eye gnats, stable flies, mosquitoes, boll weevils, pomace flies (Drosophila melanogaster), Mediterranean fruit flies, cotton bollworm, codling moth, plum curculio, and the like, can be controlled or eradicated in accordance with the methods of this invention.

Representative chemosterilants which can be used in the compositions and methods of this invention include the following:

methyl-bis- 2'chloroethyl phosphate ethyl-bis- (2-chloroethyl) phosphate butyl-bis- (2-chloroethyl phosphate octyl-bis- (Z-chloroethyl) phosphate decyl-bis 2-chloroethyl phosphate dodecyl-bis- 2-chloroethyl) phosphate octadecyl-bis- 2-chloroethyl )phosphate methyl-bis- (2-bromoethyl phosphate decyl bis- (2-bromoethyl phosphate methyl-bis- (4,4-dichlorobutyl) phosphate decyl-bis- 4,4-dichlorobutyl) phosphate ethyl-bis- (chloromethyl phosphate decyl-bis- (fluoromethyl) phosphate decyl-bisbromomethyl) phosphate butylbis- (bromomethyl phosphate meth yl-chloromethyl-2-chloroethylphosphate decyl-chloromethyl-Z-chloroethylphosphate decyl-chloromethyl-4=bromobutylphosphate decyl-2-chloromethyl-2-bromoethylphosphate The following example will illustrate the invention.

Example Decyl-bis-(2-chloroethyl)phosphate is tested against the house fly using the following procedure:

Adult flies are fed granulated sugar containing 1.0% by weight of decyl-bis-(2-chloroethyl)phosphate. Chemosterilant sugar compositions are prepared by adding 6 ml. of a solution or suspension of chemosterilant in a volatile solvent to' 10 gms. of sugar. The chemosterilant sugar compositions are allowed to dry, repulverized and placed in emergence cages which contain newly emerged adult flies. Cages containing untreated sugar are used as control. All cages are supplied with ample water. After three days the flies are examined and the mortality rate, if any, is noted. At the same time, a dish containing untreated regular fly food consisting of 6 parts sugar, 6 parts powdered non-fat dry milk and one part powdered egg yolk is added to each cage. When the flies are 6 to 7 days old, one-half inch of moist Chemical Specialties Manufacturers Association medium in a soufll cup is placed in each cage for oviposition. A few hours later each souifi cup is removed, filled with water and stirred to separate the egg masses into individual eggs. The eggs from all egg masses are mixed thoroughly and arandom sample of 100 eggs from each cageis placed a on a small piece of wet black cloth. The black cloth is then placed on moist larval medium in a rearing container. If no eggs are laid, oviposition medium is offered again at intervals of one or two days until it has been offered five times or the. flies have oviposited. Three days after oviposition the eggs are examined and the percentage hatched is determined. The larvae that hatch crawl from the cloth into the rearing medium. About 7 days after oviposition, the number of pupae are counted to determine the number of larvae that reach the pupal stage of development. The flies fed decyl-bis-(Z-chloroethyl) phosphate gave a 26% hatch of eggs and 13 pupae whereas the control flies gave a 91% hatch of eggs and 90 pupae.

In carrying out the methods of this invention, the chemosterilants can be used alone or in combination with an adjuvant in liquid, solid or gaseous form. The chemosterilant compositions of the invention are prepared by admixing the chemosterilant with an adjuvant including diluents, extenders, carriers and conditioning agents to provide compositions in the form of finely-divided particulate solids, semi-solids, aerosols, solutions and dispersions or emulsions.- Thus the chemosterilant can be used with an adiuvant such as finely-divided particulate solid, a liquid of organic origin, Water, a Wetting agent, dispersing agent, an emulsifying agent or any suitable combination of these.

Typical finely-divided solid carriers and extenders which can be used in the chemosterilant compositions of this invention include for example, the tales, clays, pumice, silica, diatomaceous earth, quartz, fullers earth, salt, sulfur, powdered cork, powdered Wood, Walnut flour, chalk, tobacco dust, volcanic ash, cottonseed hulls, wheat flour, soybean flour, tripoli, ground corn cobs, charcoals and the like. Typical liquid diluents include for example, kerosene, Stoddard solvent, hexane, benzene, toluene, water, acetone, ethylene dichloride, xylene, alcohols, diesel oil, glycols and the like. Typical liquefied gases for aerosols include for example, haloalkyls such as dichlorodifluoromethane, fluorotrichloromethane, and the like. Typical semi-solid extenders include for example, soap, petroleum jelly, and the like.

The chemosterilants also can be employed in conjunction'with attractants for the particular insect being controlled. For example, they can be applied to or admixed with attractants or baits such as sucrose, glucose, 1110- N lasses, protein mixtures, powdered egg yolk, powdered milk, yellow corn grits, quincy granules, pumice granules, sex attractants, and the like.

The chemosterilant compositions of this invention, particularly liquids and wettable particles, usually contain as a conditioning agent one or more surface active agents in amounts sufficient to render a given composition readily dispersible in water or in oil. By the term surface-active agen is understood that wetting agents, dispersing agents, suspending agents and emulsifying agents are included therein.

The term chemosterilant composition as used herein and in the appended claims includes not only compositions in a suitable form for application but also concentrated compositions which require dilution or extension with a suitable quantity of liquid or solid adjuvant prior to application.

Surface-active agents which can be used in the chemosterilant compositions of this invention are set out, for example, in Searle U.S. Patent 2,426,417, Todd U.S. 2,655,447, Jones U.S. Patent 2,412,510 and Lenher U.S. Patent 2,139,276. A detailed list of such agents is also set forth by J. W. McCutcheon in Soap and Chemical Specialties, November 1947, page 8011 et seq., entitled Synthetic Detergents; Detergents and EmulsifiersUp to Date (1960), by J. W. McCutcheon, Inc., and Bulletin 13-607 of the Bureau of Entomology and Plant Quarantine of the U.S.D.A. In general, less than about parts by-weight of the surface active-agent is present per 100 parts by weight of chemosterilant composition.

The preferred chemosterilant compositions are in the form of wettable powders, dusts, aqueous suspensions or solutions, hydrocarbon solutionsand emulsifiable oils.

Wettable powders are water-'dispersible compositions containing one or morejchernoster'ilant's and an inert solid extender. However, their performance issometimes aided by the inclusion of a wetting agent such as those listed hereinbefore. Convenience in manufacture frequently demands the inclusion of an inert, absorptive grinding aid. Suitable classes of grinding aids are natural clays, diatomaceous earth and synthetic minerals derived from silican or silicate. Preferred grinding aids include attapulgite clay, diatomaceous silica, synthetic fine silica and synthetic calcium and magnesium silicates.

The inert finely-divided solid extender for the dusts can be of vegetable or mineral origin. The solid extenders are characterized by possessing relatively low surface areas and are poor in liquid absorption. Suitable inert solid extenders for chemosterilant dusts include micaceous talcs, pyrophyllite, dense kaolin clays, ground calcium phosphate rock and tobacco dustl' The wettable powders described above can also be used in the preparation of dusts. While such wettable powders can be used directly in dust form, it is more advantageous to dilute them by blending with the dense dust diluent. In this manner, dispersing agents, corrosion inhibitors and anti-foam agents may also be found as components of a dust.

Emulsifiable oils are usually solutions of chemosterilant in water-immiscible or partially water-immiscible solvents together with a surfactant. Suitable solvents for the active ingredient of this invention include hydrocarbons and certain water-immiscible ethers, esters or ketones. Suitable surfactants are anionic, cationic and nonionic such as alkyl aryl polyethoxy alcohols, polyethylene sorbitol or sorbitan fatty acid esters, polyethylene glycol fatty esters, fatty alkylol amide condensates, amine salts of fatty alcohol sulfates together with long chain alcohols and oil soluble petroleum sulfonates or mixtures thereof, The emulsifiable oil compositions generally contain from about S te parts active ingredient, about 1 to 50 parts surfactant and about 4 to 94 parts solvent, all parts being by weight based on the total Weight of emulsifiable oil.

The chemosterilants useful in the c mpositions and methods of this invention can be prepared in various ways, e.g., by the process set forth in detail in U.S. Patent 3,010,988.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. Method for the control of house files by chemosterilization which comprises exposing house flies to a sterilizing amount of a compound of the formula wherein R and R are haloalkyl of not more than 4 carbon atoms and 3 halogen atoms, and R is alkyl of not more than 18 carbon atoms.

2. Method of claim 1 wherein R and R are chloroalkyl and R is decyl.

3. Method of claim 1 wherein R and R are-chloroethyl.

4. Method of claim 1 wherein R 'is decyl.

5.- Method of claim 1 wherein'the compound is decylbis-(2-chloroethyl)phosphate.

6. Method of claim 1 wherein the compound is ethylbis- (Z-chloroethyl phosphate.

3,492,405 5 6 7. Method of claim 1 wherein the compound is decyl- OTHER REFERENCES b1s-(2-chloromethy1)phosphate. Boikevec, Alexej, Insect Chemosterilants, vol. VII,

References Cited 6143 1966' UNITED STATES PATENTS 5 ALBERT T. MEYERS, Primary Examiner 3,010,988 11/1961 Raffelson et a1 260-461 VINCENT D. TURNER, Assistant Examiner 3,093,536 6/1963 Loeifier 16722