GB1604856A - Use of certain polyol toxicants as ectoparasiticides or ovicides - Google Patents

Abstract

The diols used have both of their hydroxyl groups in non-adjacent positions, and are preferably 2-methyl-2,4-pentanediol, or a 1,3-diol such as 1,3-butane-, 1,3-heptane- or 1,3-nonanediol or preferably 2-ethyl-1,3-hexanediol. These compositions have an ovicidal and acaricidal, and in some cases, pediculicidal activity. The diols are the only active ingredients or are parasiticidal constituents in addition to other pesticides.

Description

(54) USE OF CERTAIN POLYOL TOXICANTS AS ECTOPARASITICIDES OR OVICIDES (71) We, STAFFORD-MILLER LIMITED, of 166 Great North Road, Hatfield, Hertfordshire, a British Company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described, in and by the following statement: This invention relates to ectoparasiticidal toxicants and a method of controlling ectoparasites, including lice, other biting insects and mites. More particularly, the invention relates to the use of certain polyols as toxicants for lice, mites, and/or their ova.

There are only a relatively few ectoparasiticides which are commercially available today.

The most popular pediculicidal toxicants are Lindane (gamma benzene Malathion [S-1,2-dicarbethoxyethyl)-0 ,0-dimethyl phosphorodithioate], synergized pyrethrins and Cuprex (a combination of tetrahydronapthalene, copper oleate and acetone, the acetone not asserted to be active). Because of increased concern about the overall safety of some of the known ectoparasitic toxicants the search for new, safe and effective ectoparasiticides has intensified recently.

It is the object of this invention to provide a new, safe and effective method utilizing toxicants for ectoparasites and their ova.

According to the present invention there is provided a method of controlling ectoparasites or their ova which comprises applying to a substrate at least one non-vic diol as specified below. The method of the invention can be performed using an ectoparasiticidal or ovicidal toxicant composition comprising an active toxicant active against ectoparasites or their ova and an inert pharmaceutically acceptable carrier therefor, wherein the active toxicant is at least one of the specified non-vic diols.

The present invention also can be performed using an ectoparasiticidal or ovicidal toxicant composition comprising an active toxicant and an inert pharmaceutically acceptable carrier therefor, which contains an adjuvant toxicant which is at least one of the specified non-vic diols. Such a composition can be used in a method of controlling ectoparasites or their ova also provided by the invention and which involves applying an active toxicant to a substrate wherein at least one specified non-vic diol is applied as an adjuvant toxicant. The adjuvant toxicant is 2-methyl-2, 4-pentanediol, 1,3-butanediol, 1 ,3-heptanediol or 1,3-nonanediol.

It has now been found that certain polyols are effective ovicides, miticides and, depending on formulation are also pediculicidal. The polyols are well known compounds but the insecticidal and/or ovicidal activity thereof has not been previously known.

2-ethyl-1,3-hexanediol is well known as an insect repellent (cf. U.S. 2,407,205 and 3,836,672) and is in wide commercial use as such.

Certain polyols which are specified diols whose hydroxyl groups are in non-vicinal positions, and preferably the specified 1,3 diols, have now been found to exhibit satisfactory activity. The specified diols are 2-methyl-2,4-pentanediol, 1,3-butanediol, 1,3-heptanediol and 1,3-nonanediol. One or a combination of the toxic diols can be incorporated into an active toxicant composition which can be in the form of a liquid, powder, lotion, cream, gel or aerosol spray, or foam as the result of formulation with inert pharmaceutically acceptable carriers by procedures well known in the art. Any pharmaceutically acceptable carrier, whether aqueous or not aqueous, which is inert to the active ingredient can be employed. By inert is meant that the carrier does not have a substantial detrimental effect on the insecticidal, miticidal or ovicidal toxicant activity of the active ingredient.

The active polyol is incorporated into the toxicant composition used to treat the substrate (human, animal or inanimate) in need of such treatment, believed to be in need of such treatment, or desired to be prophylactically protected in an effective toxicant amount. By such amount is meant the amount which will cause at least 50% mortality of the ectoparasites of their ova. With respect to lice and their ova, the standard two minute immersion tests are described below. The minimum concentration of polyol in the composition required to provide an effective toxic amount varies considerably depending on the particular polyol, the particular inert pharmaceutically acceptable carrier being employed and any other ingredients which are present. Thus, in one case a 10% concentration may suffice, while in other cases, concentrations as high as 30 to 40% may be required to obtain an effective toxic dose.

The two minute immersion tests referred to above are carried out as follows: Pediculicidal activity: A 50 ml beaker is filled with tap water and allowed to come to room temperature (about 24"C). Ten young adult male and ten young adult female lice (Pediculus human us corporis) of the same age group and from the same stock colony are placed on a 2x2 cm coarse mesh patch. The sample to be tested, maintained at room temperature, is shaken until homogeneous and placed into a 50 ml beaker. The mesh patch is placed into the sample immediately after pouring, allowed to submerge, and after two minutes is removed and immediately plunged into the beaker containing the tap water. The patch is vigorously agitated every ten seconds and after one minute the patch is removed and placed on paper towelling. The lice are then transferred to a 4x4 cm black corduroy cloth patch and this point of time is considered zero hours. Thereafter, the corduroy patch is placed in a petri dish which is covered and stored in a 30 holding chamber for 24 hours.

Ovicidal activity: 15 adult, 5 to 10 day old, female lice (Pediculus humanus corporis) are placed on a 2x2 cm nylon mesh patch which is placed in a petri dish, covered and maintained in an incubator at 300C for 24 hours. The adult lice are then removed and the number of plump, viable eggs and shriveled non-fertile eggs on the patch are recorded. The sample to be tested, maintained at room temperature, is shaken until homogeneous and poured into a 50 ml beaker. Immediately after the pouring, the mesh patch is placed into the beaker, allowed to submerge, and after two minutes is removed and immediately plunged into a 50 ml beaker containing tap water at room temperature (about 24"C). The patch is vigorously agitated every ten seconds and after one minute, the patch is removed and placed on paper toweling for one minute. The patch is then placed in a petri dish which is covered and stored in the 30"C incubator. Fourteen days following treatment, a number of hatched eggs and the number of shriveled or unhatched eggs is noted.

In both the pediculicidal and ovicidal two minute immersion tests, controls are run in identical manners to that described with room temperature (24"C) tap water substituted for the sample to be tested. The results of the tests reported are net results.

It will be appreciated that the polyols can be utilized as adjunct toxicants in compositions which are otherwise insecticidal and/or ovicidal. In such compositions, the term "effective toxic amount" means the amount which will cause at least 20 c increase in the mortality of the ectoparasites exposed in the two minute immersion test relative to the same composition without the polyol.

In the following table 1, the pediculicidal and ovicidal activity of several polyols, tested in undiluted form in the two minute immersion test is set forth. Comparative results for other polyols are also set forth.

Table 1 Mortality, % Polyol Ovicidal Pediculicidal 2-methyl-2,4-pentanediol 100 0 1,3-butanediol 100 10 1,3-heptanediol 100 82 1,3-nonanediol 100 47 It will be noted that the instant polyols are excellent ovicides from Table 1. It was further surprisingly found that the pentanediol, while not prediculicidal in undiluted for, imparted pediculicldal activity to compositions which would not otherwise exhibit such activity, e.g., aqueous aliphatic alcohol solutions and aqueous aliphatic ester solutions. This fact is shown in the data presented below. Accordingly, the diols can be used to prepare compositions which are ovicidal and, in the case of the hexanediol, also pediculicidal.

Table 2 sets forth the results of testing two polyols at a 15% concentration in combination with 25% isopropanol and 60% water. For comparative purposes, it should be noted that the combination of 25% isopropanol and 75% water results in zero percent pediculicidal mortality in the same test.

Table 2 Mortality, % Polyol Ovicidal Pediculicidal 2-methyl-2,4-pentanediol 59 15 1,3-butanediol 44 5 In the following Table 3, the results of the two minute immersion test for ovicidal and pediculicidal activity for the two compounds at a concentration of 25% in combination with 15% isopropyl myristate and 60% water is set forth. For comparison, it should be noted that 15% isopropyl myristate emulsified in 85% water exhibits zero percent pediculicidal toxicity.

Table 3 Mortality, % Polyol Ovicidal Pediculicidal 2-methyl-2,4-pentanediol 34 95 1,3-butanediol 100 0 In Table 4, the results of the two minute immersion test for ovicidal activity of the four polyols as a function of concentration in water q.s. to 100% was determined.

Table 5 2-Methyl-2, 4-pentanediol, % wlw Ova Mortality, % 100 100 90 68 80 74 70 52 60 39 50 71 40 66 30 53 20 52 10 36 1,3-Butanediol, % wlw Ova Mortality, % 100 100 90 94 80 85 70 90 60 100 50 94 40 86 30 76 20 59 10 21 1,3-Heptanediol, % (wlw) in 25% isopropanol and water q.s. Ova Mortality, % 50 100 40 100 30 100 20 9.4 10 12.2 1,3-Nnonanediol, % (wiz) in 25% isopropanol and water q.s. Ova Mortality, % 50 100 40 100 30 100 20 100 10 97 The miticidal activity of the instant polyols was determined as follows. Into a one cubic foot chamber, held at room temperature, is placed a covered microscope depression slide containing ten adult mixed sex mites, Psoroptis equi var. caniculi. The slide is positioned at a distance of ten inches horizontally and four inches below the activator of a mechanical spray device and uncovered. The mechanical pump spray device delivers 50 micrograms of sample per depression of the activator. The sample to be tested, maintained at room temperature, is shaken until homogeneous and placed in the mechanical pump spray device. The primed activator is depressed twice, releasing 100 micrograms of spray mist into the closed chamber. The mist is allowed to settle an the slide containing the mites is removed and covered. This point of time is considered zero hours. The covered slide is then held at room temperature for 24 hours. Microscopic observations are noted at 0, 1, 3, and 24 hours st treatment. Controls are run in an identical manner as that described using water or the diluting agent, and net mortality results are reported. In Table 6, the activity of a 50% (w/w) concentration of the polyols in water (W) or isopropanol (I) is reported.

Table 6 Polyol Mite Mortality, % 1,3-butanediol 100 W 2-methyl-2,4-pentanediol 90 W 1,3-heptanediol 100 I 1,3-nonanediol 100 (I) Some typical end use formulations for the polyols of this invention are as follows: Clear liquid ovicidal shampoo 1,3-Butanediol 50 Triethanolamine lauryl sulfate 20 Water 30 Quick Breaking Ovicidal Aerosol Foam Mono and diglycerides from the glycerides of edible fats 8 Isopropanol 25 1,3-nonanediol 20 1,2,3-Propanetriol 5 Water 34 Isobutane 8 Ovicidal Aerosol Spray 2-Methyl-2,4-pentanediol 50 Isopropanol 25 Water 10 Isobutane 15 Illustrative examples will now be given of the use of the compounds with adjunctive toxicants. In each instance there is first given the formulation and activity of a comparison composition.

% w/w % Pediculicide Isopropanol 25 75 Phenyldimethicone 25 cs 9 Polysorbate 80 7 Water 59 Isopropanol 25 100 2-Methyl-2,4-pentanediol 15 Phenyldimethicone 25 cs 9 Polysorbate 80 7 Water 44 % W/w % Pediculicide % Ovicide Isopropanol 25 15 59 2-Methyl-2,4-pentandiol 15 Water 60 Isopropanol 25 100 60 Dimethicone 100 cs 5 2-Methyl-2,4-pentanediol 15 Polysorbate 80 7 Water 48 Various changes and modifications can be made: the various embodiments disclosed herein are for the purpose of further illustrating the invention but are not intended as limiting. Throughout this specification and claims, all temperatures are in degrees Centigrade and all parts and percentages are by weight unless otherwise indicated.

Claims (7)

WHAT WE CLAIM IS:

1. A method of controlling ectoparasites or their ova which comprises applying to a substrate at least one non-vic diol which is 2-methyl-2,4-pentanediol, 1 3-butanediol, 1,3-heptanediol or 1 ,3-nonanediol.

2. A method according to Claim 1 wherein the diol is employed in combination with an inert pharmaceutically acceptable carrier.

3. A method according to Claim 2 wherein the carrier is an aqueous carrier.

4. A method according to any one of Claims 1 to 3 wherein the diol is a 1,3 diol.

5. A method of controlling ectoparasites or their ova by applying an active toxicant to a substrate, which comprises applying with said active toxicant at least one non-vic diol as an adjuvant toxicant, the diol being 2-methyl-2,4-pentanediol, 1,3-butanediol, 1,3-heptanediol or 1,3-nonanediol.

6. A method according to Claim 5 wherein the diol is a 1,3 diol.

7. A method of controlling ectoparasites or their ova substantially as herein described and which uses one of the specified diols.