STABLE OLFACTORY REPELLENT COMPOSITION, RESULTANT ARTICLES AND METHOD OF REPELLING PESTS USING SAID COMPOSITION

Abstract: A stable olfactory repellent composition effective for repelling feral and domesticated animals consisting essentially of microcapsules comprising wormwood oil encapsulated by a material compatible with and impermeable to the oil but permeable to the vapors emitted by the oil; articles consisting of a fabricated object impregnated with or incorporating wormwood oil in an amount sufficient to repel; and the method of repelling comprising utilizing wormwood oil.

Description: STABLE OLFACTORY REPELLENT COMPOSTION, RESULTANT ARTICLES AND METHOD OF REPELLING PESTS USING SAID COMPOSITION BACKGROUND OF THE " INVENTION It is well known that rats, mice, squirrels, foxes raccoons, dogs, cats, and other feral and domesticated animals and pests cause damage to a variety of buried items, such as telephone wires and cables, as well as damage to shrubbery, gardens, packed articles of food, plastic arti¬ cles, clothing, and the like. A variety of techniques are used to either kill or repel such pests and while they are to varying degrees successful, they are either uniformly difficult to apply, or expensive, and/or in some instances toxic. Accordingly, they have met with mixed results. In addition, it is difficult, if not impos¬ sible in some instances, to incorporate the repellent with, for example, plastic material used to form underground cable because of incom¬ patibility problems or because of lack of stabil- ity after being incorporated into the plastic material used to form a covering for the cables. Consequently, there continues to be a significant economic cost due to pest damage to articles such as buried cables, wires, plants, food products and the like. Rats, for example, continue to damage a great deal of packaged stored food products, such as grains which are packaged in burlap bags. SUMMARY OF THE INVENTION A novel olfactory repellent composition, method of using the same, and articles impreg¬ nated with the same have now been found which repel feral and domesticated animals and other pests. Briefly stated, the present invention comprises a stable olfactory repellent composi¬ tion effective for repelling feral and domesti¬ cated animals consisting essentially of microcap¬ sules comprising wormwood oil encapsulated by a material compatible with and impermeable to said oil but permeable to the vapors emitted by said oil. The invention also comprises, as set forth more fully below, articles impregnated with or incorporating wormwood oil and the method of repelling animals comprising subjecting a surface from which the animals are to be repelled to the action of wormwood oil in an amount effective to repel. DETAILED DESCRIPTION While the instant invention is broadly applicable to repelling feral animals, as well as domestic animals, such as dogs, cats, and the like, and other pests, it will be described with particularity to rats and the items which they attack, such as wires, cables, and cloths. As to the repellent per se, it is wormwood oil. Wormwood oil is obtained from the dried leaves and flower tops of Artemisia absinthium L. , compositae. Such material is described in the Merck Index and it has been primarily used in the past as a flavoring in alcoholic beverages, such as vermouth and medically in the past as a bitter tonic and an anthelmintic. It has now been surprisingly found that this oil is an aversive stimulus to animals and other pests and will cause such pests to avoid an area, avoid digging in the area, and avoid items that they normally deem palatable. More¬ over, the wormwood oil causes avoidance behavior in most circumstances and under widely varying conditions. Equally importantly, while wormwood oil is offensive to pests, it is not unpleasant with respect to human olfaction. Thus, it can be used in circumstances where humans would be exposed to the order of the product. Another unexpected benefit of wormwood _ — oil is that it is persistent in yielding the amount of vapor necessary to repel feral and domesticated animals. Equally importantly, wormwood is effective when mixed with latex carriers or other plastics, such as those used for coating metal wires and cabels for surface or subsurface use. Further, the wormwood oil can be encapsu¬ lated by any of the conventional microencapsula- tion techniques to form microcapsules which can then be dispersed over an area, such as a garden, to give long-term repelling action. The composition of the shell material can be 90/50 grade polyvinyl alcohol, grade HWG car- rageenan, mixtures thereof, or equivalent encap¬ sulating material. The theoretical payload is 69.4% w/w and the range of capsule size is 250 to 850 microns in diameter. The vapor loss in ambient air for a six week period is only 2.6% at 78° F. to 82° F. and average rela¬ tive humidity of 60%. There is little reason to suspect that vapor loss would be significantly greater at higher temperatures. Not only is the wormwood oil compatible with such encapsu- lating material, but the vapors thereof are permeable with respect thereto and can be emitted from the capsules. Thus, the oil itself can be encapsulated, applied to an area to be pro¬ tected as at the periphery of a vegetable plot or shrubs or the like or a storage facility for packaged food, and continue to emit its repellent odor for substantial periods of time. It is believed that the wormwood oil would also act to protect domestic animals such as sheep and goats from attack from predators. It is known that such predators commonly and most usually kill goats and sheep by biting them in the neck and a number of articles are now proposed for use to be incorporated around the neck of such animals to protect them from attack. As set forth below, testing of the instant repellent composition against red foxes shows that it does repel the foxes and it is believed to repel such other feral animals, such as wolves and coyotes. By applying the repellent composition of the instant invention about the neck of domesticated animals, such as sheep or goats, or applying it to collars made of plastic and the like which are placed about the necks of such animals, it may act to prevent them from attack by feral predators. As to amounts, depending upon the particular circumstances and the size of area to be treated, it has been found that as little as <1 g to 125 g of wormwood oil is effective to give an olfactory scent that is repellent to feral and domesticated animals, such as foxes, rac¬ coons, opossums, gerbils, rats, dogs, cats, and the like. The particular amount for any given circumstance can be readily determined by routine experimentation. The wormwood oil is also capable of being ' incorporated into articles in order to make them repellent to pests. For example, it can be mixed with natural and synthetic latex mate¬ rials and other plastics used to make pipe or used to sheath underground cables and wires in amounts such as 10 percent by volume -and will effectively thereafter keep pests such as rats from attacking the wire or cable so coated. In addition, such materials can be impregnated with the wormwood oil and actively repel pests. Impregnation, however, is more satisfactory with cloth, such as cotton cloths used to cover articles. The invention will be further described in connection with the examples which follow which are set forth for purposes of illustration only. EXAMPLE 1 In a series of repetitive tests, strips of cloth (a 1 cm x 5 cm) were each impregnated with <0.5 g of wormwood oil and placed in cages housing gerbils together with strips of untreated cloth. The impregnated cloth strips remained intact while the untreated cloth strips were virtually pulverized. EXAMPLE 2 Pieces of electrical cable, each 15 cm in length and having a latex cover, had adsorbed on the latex cover of each <1 g of wormwood oil. Such treated pieces were placed in cages with laboratory rats together with untrated pieces of cable. The rats attacked and frayed the untreated pieces of cable and exposed the conducting wire while the treated cable pieces remained intact. EXAMPLE 3 A series of tests were run using animals that were normally fed ALPO. Some of the animals were first maintained on a deprivation diet (68% of their normal ration) and others had food withheld for 24 hours. Both groups then were given rations of ALPO which had been treated with 10 ml of wormwood oil or approximately 5 g of encapsulated wormwood oil. In all in¬ stances the animals did not ingest the treated ALPO. EXAMPLE 4 In pens housing foxes, backfilled holes were created and the foxes with apparent insa¬ tiable curiosity would react vigorously when digging at these holes. However, these same foxes did not show any interest in digging at or exploring backfilled holes in which the dirt had been treated with 5 to 10 g of encap¬ sulated wormwood oil. EXAMPLE 5 Foxes, as well as other animals, were exposed to relative large excavations that were laced with 120 g of encapsulated wormwood oil. The animals avoid the same although they ordinarily are attracted to and actively explore such excavation. While the invention has been described in connection with a preferred embodiment, it is not intended to limit the scope of the invention to the particular form set forth, but, on the contrary, it is intended to cover such alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims.

Claims: WHAT IS CLAIMED IS: 1. A stable olfactory repellent compo¬ sition effective for repelling feral and domesti¬ cated animals consisting essentially of micro- capsules comprising wormwood oil encapsulated by a material compatible with and impermeable to said oil but permeable to the vapors emitted by said oil. 2. The composition of Claim 1 wherein the encapsulating material is 90/50 grade poly- vinyl alcohol, grade HWG carrageenan, or mixtures thereof. 3. The article having an aversive stimulus to a feral or domesticated animal consisting essentially of a fabricated object impregnated with or incorporating wormwood oil in an amount sufficient to repel said animal. 4. The article of Claim 3 wherein the fabricated object is selected from a coated metal wire or cable intended for surface or subsurface use. 5. The article of Claim 3 wherein the fabricated object is a cloth. 6. The article of Claim 3 wherein the wormwood oil is encapsulated by a material compatible with and impermeable to said oil but permeable to the vapors emitted by said oil. 7. A method for repelling a feral or domesticated animal comprising subjecting a surface or area from which said animal is to be repelled to the action of wormwood oil in ' an amount effective to repel said animal there¬ from. 8. The method of Claim 6 wherein the wormwood oil is encapsulated by a material compatible with and impermeable to said oil but permeable to the vapors emitted by said oil. 9. A method for repelling a feral or domesticated animal from surface or subsurface coated wires or cables or plastic pipe comprising applying wormwood oil to said coated wires or cables or plastic pipe in an amount effective to repel said animal therefrom.

Inventors: DEAN EDWARD E, TOMLINSON SAMUEL J SR, DEAN, EDWARD, E., TOMLINSON, SAMUEL, J., SR.
Applicants: SOUTHWEST RES INST, SOUTHWEST RESEARCH INSTITUTE
Application year: 1985
Main classification: A01N65
IPC codes: A01N25, A01N65