CS195330B2 - Insecticide - Google Patents

Abstract

New pesticidal agents with low dermal toxicity towards mammals contain (a) ca 5-20 wt.% of a pesticide of the formula (C2H5O)2P(S)-S-CH2-S-R (I) (where R is C2H5 or -C(CH3)3); (b) shellac in an amt. such as to give a (I): shellac ratio of 1:1 to 3:1 w/w; (c) ca 4-6 wt.% ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol of molecular wt. 6000 and/or propylene glycol as a glycol-type deactivating agent; and (d) clay, pumice, brick dust, talc, volcanic ash, sand, li limestone dust and/or corncob grist, as solid inert carrier, making up the remainder. Granular formulations of (I) coated with shellac reduce toxicity due to percutaneous absorption about 15-fold without affecting pesticidal action.

Description

SUMMARY OF THE INVENTION The present invention provides an insecticidal composition and a process for the preparation thereof, which composition comprises a compound of the general formula as an active ingredient

where R is —C2H5 or —С (СНз) з, and has lower dermal toxicity to mammals. It is known that O, O-diethyl S- ((ethylthio) methyl) phosphorothioate and O, O-diethyl S- [(1,1-dimethylethylthio) methyl] phosphonothioate are highly effective against many insect species that attack and Therefore, it is preferable to use both of the above compounds in various compositions useful in agriculture.The disadvantage of these otherwise highly effective pesticides is that they are highly toxic to mammals when they enter the bloodstream of mammals. poisonous substances can enter the bloodstream through the digestive system and / or by inhalation, yet the most common way to get into the bloodstream is their absorption through the skin.

The use of compositions containing O, O-dl2 ethyl S - [(ethylthio) methyl] phosphorothioate and / or O, O-diethyl S - [(1,1-dimethylethylthio) methyl] phosphorothioate against soil insect pests (eg nematodes) therefore it poses a significant risk to those who apply these funds in agricultural practice. Similarly, workers in warehouses and transport are exposed to the distribution of these funds to end users. Surprisingly, it has now been found that when solid granular compositions containing the above insecticides are coated or impregnated with shellac, the resulting compositions exhibit fifteen-fold safety as a result of reducing their dermal toxicity to mammals compared to similar non-coated compositions while fully retaining their insecticidal efficiency. Usually this effect is achieved simply by applying a shellac solution to the surface of the granules.

It has been found that according to the invention particularly advantageous results are obtained when the mixture consisting of a solution of toxic active ingredient and shellac is applied to the surface of an inert granular carrier. The total composition consists of: a) the active ingredient in an amount of 5 to 20% by weight, preferably 10 to 15% by weight, based on the weight of the composition, which insecticide is composed of O, Q-diethyl-S- [[ethylthio) methyl] phosphorothioate or O, O-diethyl-S- [. (1,1-dimethylethylthio) methyl] phosphorothioate, b) shellac, which is present in a toxic compound to shellac weight ratio of 1: 1 to 3: 1, preferably 2: 1, with the remainder. The composition comprises a granular carrier which is either a sorbent material such as attapulgite or montmorillonite clay, brick fragments, pumice, talc, volcanic ash, corn sticks, or some non-absorbent. material such as sand or limestone chips. If a sorption material is selected, a deactivator such as ethylene glycol, dl-, trine or tetraethylene glycol and mixtures thereof may be added to neutralize the acidity present, in an amount of from 4 to 6% by weight of the composition. In this case, the amount of sorption material is reduced by an amount equal to the amount. a deactivator added to the composition. When a non-absorbent material, such as sand, is used as an inert solid carrier, a finely divided sorbent from the group consisting of calcined powders, diatomaceous earth, calcium silicate, oxide is added to the composition in an amount of 1 to 10% by weight. silica or mixtures thereof.

In this case, the amount of carrier is reduced by an amount equal to the amount of sorbent added to the composition. .

The novel granular coated compositions of the invention may alternatively be prepared as follows: The above toxic substance and the deactivator, consisting of liquid ethylene glycol or polyethylene glycol, are mixed and formed. the mixture is sprayed onto the surface of the inert carrier granules. When all the liquid is absorbed, the granules are heated to a temperature of 50-55 ° C, after which time the granules are heated. 20 to 30% w / v are sprayed onto their surface as they roll over to their surface. a solution of shellac in a solvent such as a lower monovalent alcohol or a mixture of lower alcohols, for example methanol or ethanol, with methylene chloride, these solvents being used in a volume ratio. 1 - 1. When the shellac coating solution is applied, the granules are rolled at a temperature. 50-55 ° C to aid evaporation of the solvent mixture. . Simultaneously, small additional amounts of a desiccant desiccant, such as calcium silicate, may be added to prevent particle aggregation. to be a means. kept in bulk. When it is . shellac coating of the granules · finished, spraying the surface of the granules with a methylene chloride solution of polyethylene glycol, for example polyethylene glycol having an average molecular weight of 6000.

In practice, it is preferable to use 1 to 5% by weight of polyethylene glycol with a molecular weight of 6000, based on the weight of the resulting granular composition. Then the granules. heat and mix, adding calcium silicate in small amounts until the mixture is heated. the coated granular composition is dry and free-flowing.

Preferably, the novel coated granular compositions of the invention are prepared by adding a pre-selected amount of the active ingredient selected from the above organophosphorus insecticides to 20-30% (w / w) by volume. a shellac solution prepared from shellac and a solvent such as a monovalent alcohol, for example methanol or ethanol, a lower aliphatic ketone, for example acetone, methyl ethyl ketone, methyl isobutyl ketoin alone or in combination with methylene chloride. Optionally, polyethylene alcohol is added to the solution of the active ingredient and shellac as a deactivator. selected from the above compounds or mixtures thereof. The solution thus prepared is sprayed onto the surface of the selected granular carrier while the granules are kept in constant motion due to known means. If the carrier selected is of the non-sorptive type, a predetermined amount of desiccant sorption compounds is admixed to the granular carrier before the granules are sprayed or added during spraying.

Preferably, a stream of warm air is applied to the surface of the granules simultaneously with spraying of the above-mentioned active ingredient solution and shellac onto the surface of the granules to promote drying and remove the solvent. After spraying, the granules so treated are kept in constant motion, being slightly heated at a temperature of 50-55 ° C and / or kept in an air stream until the composition is dry and free-flowing.

The compositions of the invention may be applied to the soil by commercially available equipment suitable for the distribution of solid pesticidal compositions. '

The invention is illustrated by the following examples. Unless otherwise stated, all parts and percentages are given. percentages and parts by weight.

Example 1

Preparation of coated granular insecticidal composition with reduced dermal toxicity

Folders %. O, O - diethyl 1-S- (ethylthio) -methylphosphorothioate [technical grade, 88,5% pure] 12.43 propylene glycol 4.0 shellac 5.0 diatomaceous earth 4.2 clay Agro-Minerals (India) 20/40 mesh, do 100.0

5.0 g of shellac with stirring. Dissolve at -5 to 50 ° C in 20 ml methanol. To this solution was added 12.4 g of O, O-diethyl-S- ¹ (ethyl alcohol) methyl 195330.

88.5 g of 4.0 g of propylene glycol and the mixture was stirred until a homogeneous solution was obtained. Now granulated clay (up to IDO%) and 4.2 g diatomaceous earth were added to the rotary mixer. While the blender is in operation, it is sprayed on, the above-prepared methanolic shellac solution is sprayed onto the mixture of granulated clay and lignite earth, while simultaneously introducing an air stream into the mixer cavity. Once spraying of the solution is complete, mixing is continued. The air flow is also continued to the cavity of the mixer until the granules are dry and free-flowing.

The Agro-Minerals clay (India) used in the preparation of the insecticidal composition has the following composition:

Analysis% silica39.15 iron oxide5.01 titanium dioxide6.84 aluminum oxide29.22 manganese oxide0.02 calcium oxide1.88 magnesium oxide1.08 potassium oxide0.03 sulfuric oxide .0.20 specific mass at 30/30 ° C = 2.86 pH (10% aqueous suspension) = 7.2 oil absorption29.91

However, using the above procedure but substituting O, O-diethyl S - [(ethylthio) methyl] phosphorothioate with O, O-diethyl S - [(1,1-dimethylethylthio) methyl] phosphorothioate, a coated granular granule is prepared. an insecticide composition comprising the indicated O, O-diethyl S - [(1,1-dimethylethylthio) methyl] phosphorothioate.

Example 2

Preparation of coated granular insecticidal composition with reduced dermal toxicity

The procedure is as in Example 1, except that the composition is prepared from the following ingredients:

Folder / o

O, O-diethyl-S - [(ethylthio) methyl] phosphorothioate of 88.5% purity 12.43 propylene glycol 4.0 polyethylene glycol mol.

weight 60001.0 shellac5.0 calcium silicate1.0 clay Agro-Minerals (India) **

20/40 mesh, up to 100.0

As described above, but using O, O-diethyl-S - {(1,1-dimethylethylthio) methyl] phosphorothioate instead of the above active ingredient, a coated granular insecticidal composition containing 11.0 percent O, O-diethyl-S is prepared. - [(1,1-dimethylethylthio) methyl] phosphonothioate.

? 1 and d 3

Preparation of coated granular insecticidal composition with reduced dermal toxicity

Folders .'%

O, O-diethyl S - [(1,1-dimethylethylthio) methyl) phosphorothioate with a purity of 88.5% 12.43 propylene glycol 2.00 polyethylene glycol mol.

weight 00003,33 shellac5,50 attapulgit * ^** 24/48 mesh, clo100,0 * = attapulgite composition shown at the end of the example

To produce 100 grams:

5.50 g of shellac are dissolved in 25 ml of methanol at 45-50 ° C with stirring. 12.43 g of O, O-diethyl S - [(1,1-dimethylethylthio) methyl] phosphorothioate of 88.5% purity, 2.0 g of propylene glycol and 3.33 g of polyethylene glycol of molecular weight 6000 are added to the obtained solution. ; the mixture obtained is stirred until a homogeneous solution is obtained.

Clay granules are added to the rotary mixer (up to 100%). While the mixer is in operation, the above prepared methanolic solution is sprayed onto the mixture of clay granules while simultaneously introducing an air stream into the mixer cavity. After spraying of the solution, mixing is continued and the air stream is still supplied to the mixer cavity until the granules are dry and free-flowing.

As described above, but using O, O-diethyl S - [(ethylthiomethylmethylphosphorothioate) as an active ingredient, a coated granular insecticidal composition containing 11% O, O-diethyl S- [[ethylthio) methyl] phosphorothioate can be prepared.

The composition of attapulgite (Attaclay A LVM) dried at 105 ° C is as follows:

* = polyethylene glycol with an average molecular weight of 6000 ** = composition given in Example 1 θ / ο silicon dioxide64,37 oxide -. aluminum12,46 iron oxide5,93 magnesium oxide5,28 calcium oxide0,99 sodium oxide0,05 potassium oxide1,58 titanium dioxide0,73 loss on ignition8,21

Example 1 a d 4

Preparation of coated granular insecticidal composition with reduced dermal toxicity

Percent

Weight / weight components

O, O-diethyl S - [(ethylthio) methyl] phosphorothioate (technical grade, 88.5% pure) 12.43 propylene glycol 4.00 polyethylene glycol mol.

weight 6000 1.00 shellac 5.00 calcium silicate (200 mesh) 1.00 clay Agro-Minerals (India) * *

20/40 mesh to - 100.00 * = analysis given in Example 1.

parts of propylene glycol and 122 parts of O-ethyl-S- (ethylthio) methylphosphorothioate of 90% purity are mixed and mixed until a homogeneous solution is obtained, hereinafter referred to as solution A. 50 parts. The shellac powder was dissolved with stirring in 125 parts by volume of methanol and then diluted to 250 parts by volume with methylene chloride. The resulting solution is then filtered. This is referred to as solution B. Then 10 parts of 6000 molecular weight polyethylene glycol are mixed with 50 parts by volume of methylene chloride and the resulting mixture is stirred until a homogeneous solution is obtained, hereinafter referred to as solution C.

The Agro-Minerals granulated clay is then introduced into the roll-type mixer. The granules are sprayed with solution A during operation of the roll-over mixer. after spraying the solution .A, the granules are mixed for at least 5 minutes. Immediately thereafter, the contents of the mixer are heated with hot air to a temperature of 50-55 ° C and sprayed on the rolling granules with a solution of shellac B in such an amount as to. the surface of the granules being slightly wet while maintaining the temperature of the granules in the range of 50-55 ° C. After application of a certain proportion of solution-B, the granules may begin to aggregate into clusters. Therefore, calcium silicate is added in small portions between application of solution B so that the granules remain free-flowing. After spraying all of the solution B onto the granules, mixing and rolling of the granules is continued, spraying the granules in small portions with a 6000 molecular weight methylene chloride solution C of polyethylene glycol alternating with the addition of small amounts of calcium silicate to keep the granules free flowing.

After addition of all the solution - C, mixing is continued and, if necessary, additional calcium silicate is added to keep the granules free-flowing. The granules are then sieved through 10 and 100 mesh sieves to remove agglomerates and fines. This gives approximately 1000 grams of a granular coated insecticide composition containing 12.43% of O, O-diethyl-S- (ethylthio) methylphosphorodithioate.

Examples 5 to 13

Preparation of coated granular insecticidal compositions

The coated granular insecticidal compositions listed in Table I can be prepared by the procedure of Example 4.

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Example 14

Preparation of coated granular insecticidal composition with reduced dermal toxicity

Weight

Folders parts O, O-diethyl-S- (ethylthio) methyl- Phosphfordithioate (technical, 90% pure) 122 propylene glycol 40 shellac 100 ALIGN! diatomaceous earth 42 clay Agro-Minerals (India) 20/40 mesh, do 1000

100 parts of shellac are dissolved with stirring at 45 to 50 ° C in 250 parts by volume of methanol and 122 parts of O, O-diethyl-S- (ethylthio) methylphosphorothioate of 90% purity and 40 parts of propylene glycol are added to this solution. The resulting mixture was stirred vigorously until a homogeneous solution was obtained.

Granulated clay (up to 1000) and 42 parts of diatomaceous earth were added to the rotary mixer. While the mixer is in operation, the above homogeneous methanolic shellac solution is sprayed onto the mixture of granulated clay and diatomaceous earth, while simultaneously introducing an air stream into the mixer cavity; once spraying of the solution is complete, mixing is continued. Also, the air stream continues to be fed into the mixer cavity until the granules are dry and free-flowing.

Above. said clay Agro-Minerals (India) has the following composition:

Example 15

Preparation of a 'granular' insecticide formulation with reduced dermal toxicity

The procedure of Example 14 is attempted, except that the composition is prepared from the following ingredients:. '

Weight

Folders parts O, O-diethyl S - [(ethylthiomethyl) phosphorothioate of 90% purity. propylene glycol 40 polyethylene glycol mol. weight. * 000 * 10 shellac 100 ALIGN! calcium silicate '10 clay Agro-Minerals (India) ** 20/40 mesh, do. 1000 * = polyethylene glycol of average molecular weight

weight 6000.

** = composition shown in Example 1.

Using the above procedure, but using O, O-diethyl S - [(1,1-dimethylethylthio) methyl] phosphorothioate instead of the above active ingredient, a coated granular insecticidal composition containing 11% of said O, O-diethyl- S - [(1,1-dimethylethylthio) methyl] phosphorothioate.

Example 16

Preparation of coated granular insecticidal composition with reduced dermal toxicity silicon dioxide39,15 iron oxide5,01 titanium dioxide6,84 aluminum oxide29,22 manganese oxide0,02 calcium oxide1,88 potassium oxide0,08 potassium oxide0,03 sulfur trioxide0,20 sulfur trioxide0,20 sulfur dioxide 45 specific mass at 30/30 ° C = 2.86 pH (10% aqueous suspension) = 7.2 oil absorption29.91

Using the above procedure, but using O, O-diethyl-1S - [(1,1-dimethylethylthio) methyl] phosphorothioate instead of O, O-diethyl S - [(ethylthio) methyl] phosphorothioate, a coated granular insecticidal composition is obtained, containing O, O-Li-11- [1,1-dimethylethylthio) methyl] phosphorothioate.

Folders : Weight parts O, O-diethyl-S - [(1,1-dimethyl- ethylthio) methyl] phosphor- 90% pure dithioate 122 propylene glycol 20 May shellac 100 ALIGN! polyethylene glycol mol. weight 6000 10 attapulgit * 24/48 mesh, do 1000

* = composition shown at the end of the example.

100 parts of shellac are dissolved in 250 ml of methanol at 45-50 ° C with stirring. To the obtained solution were added 122 parts of OO-diethyl-S - [(1,1- (1ϊΓηθ ^ 1θ№ííHH)) methyl] phosphorodithioate of 90% purity, 20 parts of propylene glycol and 30 parts of polyethylene glycol of molecular weight 6000, and the mixture was mí195330 no

It is kept until a homogeneous solution is obtained. . ; '””

Granular clay (up to 100%) is added to the rotary mixer. While the mixer is in operation, the methanolic solution prepared above is sprayed onto the granulated clay, while a stream of air is simultaneously introduced into the cavity of the mixer. Mixing is continued even after the solution has been sprayed, and the air flow to the mixer cavity is also continued until the granules are dry and free-flowing.

Using the above procedure, but using O, O-diethyl S - ([(ethylthio) methyl] phosphorothioate instead of the above toxic active ingredient, a coated granular insecticidal composition containing 11.0% of said O, O-diethyl- S - [(ethylthio) methyl] phosphorothioate.

The composition of attapulgite (Attaclay A LVM) dried at 105 ° C is as follows:

Components% Silicon dioxide64.37 Aluminum oxide12.46 Iron oxide5.98 Magnesium oxide5.28 Calcium oxide0.99 Sodium oxide0.05 Potassium oxide1.58 Titanium dioxide0.73 Loss on ignition8.21

Example 17

Preparation of coated granular insecticidal composition with reduced dermal toxicity%

Weight / weight components

Ο, Ο-diethyl 1-S - [(ethylthio) methyl] phosphorothioate (technical grade, 90% pure) 12,23 propylene glycol 4,00 polyethylene glycol mol.

weight 6000 1.00 shellac 10.00 talc (200 mesh) 10.00 clay Agro-Minerals (India) * *

20/40 mesh, up to 100.00 * = composition shown in Example 1.

To 40 parts of propylene glycol are added 122 parts of O, O-diethyl S - [(ethylthio) methyl) phosphorothioate of 90% purity and the resulting mixture is stirred until a homogeneous solution is formed, hereinafter referred to as solution A. 250 parts by volume of methanol dissolve 100 parts of shellac powder, then dilute the solution to 500 parts with methylene chloride and filter. The filtered solution is hereinafter referred to as solution B. Then 10 parts of 6,000 molecular weight polyethylene glycol is mixed with 50 parts by volume of methylene chloride and stirred until a homogeneous solution is formed, hereinafter referred to as solution C.

1000 parts of granulated clay are introduced into the roll-type mixer. While the mixer is in operation, solution A is sprayed onto the rolling granules, and after the addition of solution A is complete, the granules are mixed for at least 5 days. Immediately thereafter, the contents of the mixer are heated to 50-55 ° C with a hot air stream, and the shellac solution is sprayed onto the rolling granules in an amount such that the granule surface is slightly wet while maintaining the temperature of the granules at 50-55 ° C. After application of a portion of solution V, the granules may begin to form clumps. In this case, talc is added in small portions between the individual injections to keep the granules free-flowing. After all of the solution V has been sprayed onto the granules, the mixing and rolling of the granules is continued, spraying in small portions with a 6000 MW molecular weight methylene chloride solution C alternating with the addition of small amounts of talc to keep the granules free flowing.

After the addition of solution C is complete, mixing is continued and, if necessary, additional talc is added to keep the granules free-flowing. The granules are then sieved through 10 and 100 mesh screens to remove agglomerates and fines. Approximately 1000 g of a granular coated insecticide composition containing 12.23% of O, O-diethyl-S - [(ethylthio) methyl] phosphorothioate is obtained.

Example 18

The procedure of Example 17 is repeated except that a solution of 80 parts of shellac powder in 200 parts by volume of methanol is used.

Example 1 a d 1 9

Determination of LD50 in dermal dry-coated granular formulations containing 11% by weight of O, O-diethyl-S- (ethylthio) methylphosphorithioate on white rats as test animals

Experimental animals:

The test animals are white rats of the type Charles Foester of 150 to 224 g in arbitrary groups of 5 animals each.

Testing means:

Means for the first two groups of attempts19 * 33 O ττ '7 ......

13 animals were prepared according to the procedure of Example 4 and for the remaining three experimental groups. animals according to the procedure of Example 14; their composition is shown in Table II.

Table II

Compound Control I II III IV V

O, O-diethyl-S- (ethylthio) methyl-

thylphosfordithioate. 100% pure 11.0 11.0 propylene glycol 4.0 , 4.0 polyethylene of mol. 'hm- 6000 - 1.0 shellac - ’ 5.0 calcium silicate. 1.0 1.0 clay Agro-Minerals (India) 20/40 mesh, do 100,0 ' 100.0

11.0 11.0 11.0 11.0 4.0 4.0 4.0 4.0 1.0 1.0 1.0 1.0 5.0 10.0 10.0 10.0 1.0 10.0 10.0 10.0 100.0 / ^^ 0.0 100.0 100.0

The test devices are evaluated using the following doses:

Control: 250, 200, 150, 100 and 75 mg / kg body weight.

Formulations I and II: 1710, 1135, 760, 505 and 340 mg / kg body weight.

Formulations III and IV: 3875, 2583, 1722, 1148, 765, and 510 mg / kg body weight.

Composition V: 5812, 3875, 2583, 1722, 1148, 776 and 510 mg / kg body weight.

Each dose was tested on five animals.

Method:

Each animal is shaved on its back and sides. The selected doses of the above compositions are then uniformly covered with animal skin, which is then covered with aluminum foil. The rat's body is then wrapped with a 7.5 x 22.5 cm adhesive tape to adhere the device and the aluminum foil it covers to the rat skin; the elastic tape is then tightened sufficiently to:. the animal could not free itself by winding, and wrapped around the animal's body once more to form a double layer of Tape.

The animals are then housed one by one in a cage for 24 hours. After this time, the tape is removed and the animal skin and surrounding hair is then thoroughly washed with a 'sponge' with a solvent-free detergent and warm water, then rinsed and dried with a towel.

The animals are then re-housed and observed for seven days or until the infected animals have clinically recovered. LD 50 values are calculated from the number of animals that have died, which are as follows:

Formulation 'LD 50' mg / kg body weight.

Control 148

I 931

II 803

III 2400

IV 2160

V 2280

It follows from the foregoing that the coated granular compositions of the present invention are substantially safer to the skin than conventional granular compositions containing O, O-diethyl-S- (ethylthio) methylphosphorothioate.

Example 20

Evaluation biocidal. the effectiveness of coated granular insecticidal compositions when used against soil insects and mites

For these plates, a coated granular composition containing O, O-dimethyl-S- (ethylthiomethylphosphorothioate) and a standard granular composition containing the same pesticide are prepared as described in Example 4. The composition of both compositions is shown in Table III.

Table III

Weight percent

Component

A (unpacked standard)

В (coated device)

O, O-Diethyl-S- (ethylthio) methylphosphoryl thioate with a purity of 100% propylene glycol polyethylene glycol of molecular weight 6000 shellac calcium silicate clay Agro-Minerals (India) 20/40 mesh

11.0

4.0 to 100

11.0

4.0

1.0

5.0

1.0 to 100

Systemlcký test;

The efficacy of these formulations against antipyroptera (Empoasca abrupta DeLong) and against spider mite (Tetranychus urticae Koch) against organophosphates at doses of 7.5, 15 and 30 mg of active ingredient per soil in a 10 cm plastic pot is compared. . The treatment and the untreated control are repeated three times.

Method:

The granules are spread evenly over the surface of a 2.5 cm high layer of soil in pots. Cotton plants at the 2-3 leaf stage are transplanted to the treated soil surface and then covered with untreated soil. The transplanted cotton plants are placed in a greenhouse and watered thoroughly until the soil is soaked.

Three days after treatment, both cotyledons of each cotton plant are cut off and placed in petri-pans of bio-tests with pimples. The right leaves are left on the plants and infect the spider mite.

The mortality of both insects is determined after 3 days after infection (six days after soil treatment). The average values of the data obtained are shown in Table IV.

Table IV

Efficacy of coated granular composition against peacock and spider mite in systemic test average

Resources mg active ingredient // pot mortality rate, pimpernel of 3 repetition spider moth A (unpacked standard) 7.5 100 ALIGN! 100 ALIGN! 15.00 100 ALIGN! 100 ALIGN! 30,00 100 ALIGN! 100 ALIGN! В (coated device) 7.5 100 ALIGN! 100 ALIGN! 15.00 100 ALIGN! 100 ALIGN! 30,00 100 ALIGN! 100 ALIGN! Control —- 0 0

All tested doses of both agents achieve 100% death of the peacock and spider mite. This implies that O, O-diethyl S- (ethylthio) methylphosphorodithioate is properly released from the coated formulation (B) and that the active ingredient is absorbed by the cotton plants as efficiently as it is absorbed from the standard uncoated formulation (A).

Soil test against beetles (Diabrotica unde. Cipunctata howardl):

In this test, the efficacy of the above-described A and V compositions against soil beetles (Diabrotica undipipunctata howardi Barber) is compared.

Approximately 3/4 of the soil is treated with 1, 5 and 10 mg of the active ingredient. The granules are added to the moist soil and mixed mechanically for 2 minutes to achieve a uniform distribution of the granules in the soil. At each concentration, 5 soil samples of 28.35 grams are placed in glass vials of 1 ml millet seeds. The contents of the containers are mixed and then infected with 10 beetle larvae. Six days after treatment, morphality is detected. The average values from the data are shown in Table V.

19'5'3 3 (1 ···. ·. Table V

Biocidal efficacy of coated granular anti-beet (Diabrotica undecipunctata howardi Barber) mortality percentage average of 5 replicates

means mg of active ingredient / / 3/4 liter of soil ' flea beetle (Diabrotica undecipúnctata howardi) A (unpacked standard) 1 ' 100 ALIGN! • 5 100 ALIGN! 10 100 ALIGN! B (coated device) 1 100 ALIGN! 5 100 ALIGN! 10 100 ALIGN! Control - 0

At all concentrations of the two formulations, 100% mortality of the beet larvae was achieved. The results of this test illustrate the results obtained in the aforementioned systemic test being investigated. the coated formulation B releases the active ingredient properly and is as effective as standard formulation A.

Claims (10)

OBJECT OF THE INVENTION An insecticidal composition having reduced dermal toxicity to mammals, characterized in that it comprises - 5 to 20% by weight, based on the weight of the composition, of an active ingredient of the formula I, (PP-S-CHfS-R '*) means a radical -C2H5 or -С (СНз) з, - shellac in an amount corresponding to the ratio of the weight of active ingredient to the weight of shellac in the range of 1: 1 to 1: 3, - 4 to 6% by weight of a glycol deactivator from ethylene glycol, diethylene glycol , triethylene glycol, tetraethylene glycol, polyethylene glycol of average molecular weight 6000, propylene glycol, and mixtures thereof, and - a solid inert support - from the group consisting of clays, pumice stone, talc, talc, volcanic ash, sand, limestone pulp and pulp of corn sticks. 2. A composition according to claim 1 wherein the weight ratio of active ingredient to shellac is 2: 1. 3. A composition according to claim 1 comprising 10 to 15% by weight of the active ingredient in admixture with 1 to 6% by weight of a sorbent, comprising calcium silicate, diatomaceous earth or silica. 4. A composition according to claim 1, wherein the active ingredient is O, O-diethyl S - [(ethylthio) methyl] phosphorothioate. 5. A composition according to claim 1, wherein the active ingredient is O, O-diethyl S - [(1,1-dimethylethylthio) methyl] phosphor dithioate. 6. A composition according to claim 1 comprising 10 to 15% by weight of O, O-diethyl S - [(ethylthio) methyl] phosphonothioate, wherein the weight ratio of active ingredient to shellac is 2: 1, in admixture with an inactivator , consisting of propylene glycol or polyethylene glycol of an average molecular weight of 6000, or mixtures thereof, to which is admixed as an anti-coupling agent and a desiccant, calcium silicate or diatomaceous earth, and as an inert carrier comprises attapulgite or montmorillonite clay. 7. A composition according to claim 6, wherein the active ingredient is O, O-diethyl S - [(1,1-dimethylethylthlo) methyl] phosphorothioate. 8. The composition of claim 1 wherein all components are dissolved in methanol, ethanol, acetone, or methyl ethyl ketone alone or in combination with methylene chloride, wherein the sum of the weight% of said components together with the weight% solid carrier onto which said liquid is present. the mixture applied is equal to 100%. 9. A process for the preparation of an insecticidal composition having reduced dermal toxicity to mammals according to claim 1, characterized in that 20 to 30% w / v is first prepared. solution of shellac in an inert solution. a solvent comprising methanol, ethanol, acetone or methyl ethyl ketone, 5 to 20% by weight of an active compound of formula I wherein R is as defined above and 4 to 6% by weight of a glycol deactivator selected from the group consisting of ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol 6000 molecular weight, propylene glycol, or mixtures thereof containing 1 to 5% average molecular weight 6000 polyethylene glycol in said mixture, and then the solution thus prepared is applied to a solid support surface selected from the group consisting of clay, pumice, brick pulp, talc, volcanic ash, sand, limestone pulp or corncob pulp, wherein the carrier may also comprise a finely divided powdered sorbent selected from the group consisting of calcium silicate, diatomaceous earth or silica in an amount of 1 to 10% by weight, and wherein the sum by weight 100%, and the solvents are evaporated by heating at a temperature between 50 and 55 ° C until the composition is dry and free-flowing, and the weight ratio of active ingredient to shellac is in the range of 1: 1 to 3: 1 . 10. The process of claim 9 further comprising adding methylene chloride to the inert solvent used to dissolve the shellac.