JPH07187924A - Controlling agent against psychodidae and phoridae - Google Patents

Abstract

PURPOSE:To obtain a controlling agent effective against various pests, esp. Psychodidae and Phoridae, breeding from or living in purification tanks and other wastewater disposal facilities. CONSTITUTION:This controlling agent contains, as active ingredient, N-(2,6- difluorobenzoyl)-N'-(2-fluoro-4-trifluoromethylphenyl)urea. This agent has extraordinarily excellent effect, at low doses, for controlling and preventing the breeding of the larvae, pupae and imagoes of Psychodidae and Phoridae, its dose being 0.001-1000ppm in terms of the level of the active ingredient. This controlling agent can further be formulated with at least one kind of agent selected from insect growth inhibitors, pyrethroid-based insecticides, pyrethroid-like insecticides, organophosphorus-based insecticides, carbamate-based insecticides and chloronicotine-based insecticides, and a synergistic agent such as butyl carbitol, 6-propyl-piperonyl ether or N-octylbicycloheptene carboxyimide.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pest control agent for flies and flies that occur in septic tanks and wastewater treatment facilities.

[0002]

2. Description of the Related Art With the spread of septic tanks in recent years, sanitary pests such as mosquitoes and cockroaches and unpleasant pests such as fly flies, fleas, chironomids, and spiders have become a problem.
The septic tank must be maintained and inspected at regular intervals according to the Ordinance of the Ministry of Health and Welfare, and when the maintenance and inspection worker opens the manhole and works, it enters the mouth and nose and interferes with the work. In addition, various pests generated in the septic tank enter the room from the septic tank and cause discomfort to humans, and it is desired to exterminate these pests. In particular, butterfly flies such as Drosophila melanogaster, Drosophila melanogaster, and flea flies such as Pleurotus chinensis flies, fleas fly fleas, and horn fly flies crawl scum and wall surfaces floating in the wastewater of various septic tanks, and adults are generally nocturnal activities. In the daytime, it is stationary in the shade, but at night it crowds in humid places such as toilets, kitchens, bathrooms, etc., which is not only unpleasant, but at times it is thought that it may contaminate food etc. The effective extermination is longed for. Conventionally, as agents for controlling hygienic pests and unpleasant pests generated in such septic tanks, organic phosphorus compounds such as dichlorvos and pyrethroid insecticides such as empensulin, juvenile hormone-like compounds such as pyriproxyfen (J
HM agent) is used. An example of the use of a chitin synthesis inhibitor in this type of control agent is N-2,6-difluorobenzoyl-N'-4-chlorophenylurea (generic name; diflubenzuron), which is insoluble in water and floats in water. JP-A-2-247102 discloses that it can be contained in a substance and used as a pest control agent for a septic tank. On the other hand, N-2,6-difluorobenzoyl-N'-
2-Fluoro-4-trifluoromethylphenylurea is useful as a pest control agent for lepidopteran larvae such as diamondback moth, Spodoptera litura and Nikameichu, and dipteran larvae such as Culex pipiens. It is described in the official gazette.

[0003]

However, dichlorvos, which is used as a control agent of this kind by impregnating a resin plate in a septic tank, is a highly toxic chemical per se, so it must be handled with extreme caution. Is.
In addition, pyrethroid insecticides and the like used as an oil agent can exterminate adults in the septic tank at the time of treatment, but the effect cannot be sustained for a long time against newly emerged adults from larvae and pupae that could not be exterminate. However, in order to completely carry out the control, it is necessary to carry out direct spraying and fumes several times within 1 to 3 weeks in the septic tank, which is a problem that it takes time and cost. As a method for exterminating larvae, organophosphorus or pyrethroid insecticides, hydrating agents such as JHM agents, etc. are sprayed on the sewage, but high-concentration drug treatment is required, and therefore it is included in the drug. There is a problem in that the amount of spray is extremely difficult to set because no one can easily spray it, because the activated sludge in the septic tank may be adversely affected by the solvent that is present and the function of the septic tank may be lost. Further, as a method for simultaneously exterminating adults and larvae, a JHM agent such as a pyrethroid insecticide or pyriproxyfen is sprayed on the surface of scum or sewage as an aerosol agent, but larvae of some insect pests such as fleas are larvae. In extermination, there is a problem in efficacy, such as a large amount of spraying is required. As described above, although there are various methods for controlling various pests that occur in septic tanks, in terms of the control effect, the sustainability of the control effect, especially in terms of exterminating fly flies and fleas flies, etc. There was no satisfactory pesticide.

[0004]

Means for Solving the Problems The present inventors have proposed a septic tank,
As a result of earnest studies on various pests generated from other sewage treatment facilities, etc., and various pests inhabiting there, in particular, effective pesticides for controlling fly flies and fleas.
It has been found that N-2,6-difluorobenzoyl-N'-2-fluoro-4-trifluoromethylphenylurea (hereinafter referred to as the present compound) exhibits a superior effect in controlling fly flies and fruit flies. The present invention has been completed.

That is, the present invention provides the following insecticides for fleas and fleas, as well as an agent for sterilizing flies and fleas for septic tanks. (1) Pesticide flies and fleas flies control agent containing the present compound as an active ingredient (2) The present compound and at least one or more pest control agents selected from the following group as an active ingredient Insect-controlling composition for flies and fleas, characterized by containing insect growth inhibitor Pyrethroid insecticide Pyrethroid-like insecticide Organic phosphorus insecticide Carbamate insecticide Chlornicotine insecticide (3) Using this compound as an active ingredient Disinfectant for a septic tank and fleas flies for septic tanks containing (4) this compound and at least one or more pest control agents selected from the following groups as septic tanks Pest-flies and fleas fly control composition for insects Insect growth inhibitor Pyrethroid insecticide Pyrethroid-like insecticide Organophosphorus insecticide Car Mate insecticides chloro nicotine insecticides (5) above (1) to (4) to each of the pesticides and control composition, characterized by formulating a synergist

Examples of insect growth inhibitors, pyrethroid insecticides, pyrethroid-like insecticides, organophosphorus insecticides, carbamate insecticides and chlornicotine insecticides used in the present invention include the following compounds. , Its optical isomers and geometric isomers, or a mixture thereof. Also, as an insect growth inhibitor, JHM
Agents, anti-juvenile hormone-like compounds (Anti JH agents), chitin synthesis inhibitors and the like.

JHM agent: (1) 2- [1-methyl-2- (4-phenoxyphenoxy) ethoxy] pyridine (2) isopropyl-11-methoxy-3,7,11-
Trimethyldodeca-2,4-dienoate (3) Ethyl-3,7,11-trimethyldodeca-2,
4-dienoate

Chitin synthesis inhibitor: (4) 1- (4-chlorophenyl) -3- (2,6-difluorobenzoyl) urea (5) N-cyclopropyl-1,3,5-triazine-
2,4,6-triamine (6) 2-t-butylimino-3-isopropyl-5
Phenylperhydro-1,3,5-thiadiazine-4
-One (7) 1- (3,5-dichloro-2,4-difluorophenyl) -3- (2,6-difluorobenzoyl) urea (8) 1- (4-trifluoromethoxyphenyl) -3
-(2-Fluorobenzoyl) urea

Pyrethroid insecticides and pyrethroid-like insecticides: (9) 5-benzyl-3-furylmethyl chrysanthemate, 5-benzyl-3-furylmethyl (1R) -chrysanthemate (10) 3,4 5,6-Tetrahydrophthalimidomethyl chrysanthemate (11) 3,4,5,6-Tetrahydrophthalimidomethyl (1R) -chrysanthemate (12) 3-phenoxybenzyl chrysanthemate

(13) 3-phenoxybenzyl (1
R) -chrysanthemate (14) 3-phenoxybenzyl 3- (2,2-dichlorovinyl) -2,2-dimethylcyclopropanecarboxylate (15) 3-allyl-2-methyl-4-oxocyclopento- 2-enyl chrysanthemate (16) 3-allyl-2-methyl-4-oxocyclopent-2-enyl (1R) -chrysanthemate (17) 1-ethynyl-2-methyl-2-pentenyl
(1R) -Chrysanthate

(18) (S) -2-Methyl-4-oxo-3- (2-propynyl) cyclopent-2-enyl (1R) -chrysanthemate (19) α-cyano-3-phenoxybenzyl chrysanthe Mart (20) α-cyano-3-phenoxybenzyl (1
R) Chrysanthemate (21) 3-allyl-2-methyl-4-oxocyclopent-2-enyl 2,2,3,3-tetramethylcyclopropanecarboxylate (22) 2,3,5,6- Tetrafluoro-4-methylbenzyl 3- (2,2-dichlorovinyl) -2,2-
Dimethyl cyclopropanecarboxylate

(23) 2,3,5,6-tetrafluoro-4-methylbenzyl (1R) -trans-2,2-
Dimethyl-3- (2,2-dichlorovinyl) cyclopropanecarboxylate (24) (S) -α-cyano-3-phenoxybenzyl (1R, 3S) -2,2-dimethyl-3-[(RS)
-1,2,2,2-Tetrabromoethyl] cyclopropanecarboxylate (25) α-cyano-3-phenoxybenzyl 2-
(4-chlorophenyl) -3-methylbutyrate (26) (S) -α-cyano-3-phenoxybenzyl 2- (4-chlorophenyl) -3-methylbutyrate (27) α-cyano-3-phenoxybenzyl Two
2,3,3-tetramethylcyclopropanecarboxylate

(28) α-Cyano-3-phenoxybenzyl 3- (2,2-dichlorovinyl) -2,2-dimethylcyclopropanecarboxylate (29) α-Cyano-3-phenoxybenzyl 2-
(2-chloro-4-trifluoromethylanilino) -3
-Methyl butyrate (30) 2- (4-ethoxyphenyl) -2-methylpropyl 3-phenoxybenzyl ether

Organophosphorus insecticide: (31) O, O-dimethyl O- (3-methyl-4-nitrophenyl) phosphorothioate (32) 2,2-dichlorovinyl dimethyl phosphate (33) O, O-diethyl O -(2-isopropyl-
6-Methyl-4-pyrimidinyl) phosphorothioate (34) (E) -O-2-isopropoxycarbonyl-
1-Methyl vinyl O-methyl ethyl phosphoramido thioate (35) O, O-diethyl O- (3,5,6-trichloro-2-pyridinyl) phosphorothioate (36) O, O-dimethyl O- (3,3 5,6-Trichloro-2-pyridinyl) phosphorothioate (37) S-6-chloro-oxazolo (4, b-5) pyridin-2 (3H) one-3-yl-methyl O, O-dimethyl phosphorothioate

Carbamate insecticide: (38) 5-methoxy-3- (2-methoxyphenyl)
-1,3,4-oxadiazol-2 (3H) -one (39) 2- (1-methylethoxy) phenyl methylcarbamate (40) 1-naphthyl N-methylcarbamate

Chlornicotine insecticide: (41) 1-[(6-chloro-3-pyridinyl) methyl] -4,5-dihydro-N-nitro-1H-imidazol-2-amine (42) N- [ (6-Chloro-3-pyridinyl) methyl] -N'-cyano-N-methyl-ethaneimidamide (43) N-[(6-chloro-3-pyridinyl) methyl] -N-ethyl-N'-methyl-2 -Nitrovinylidene diamine

Examples of synergists used in the present invention include:
Butylcarbitol 6-propyl-piperonyl ether (hereinafter, referred to as piperonyl butoxide), octachlorodipropyl ether (hereinafter, referred to as S-421), isobornyl cyanate acetate (hereinafter, I).
It is written as BTA. ), N-octylbicycloheptenecarboximide (hereinafter referred to as cinepyrine 222),
N- (2-ethylhexyl) -1-isopropyl-4-
Methylbicyclo (2,2,2) oct-5-ene-2,
Examples thereof include 3-dicarboximide (hereinafter referred to as cinepyrine 500).

When the present compound and the pest control agent used in the present invention are used as the active ingredient of the pesticide or the pesticidal composition of the present invention, it is usually mixed with a solid carrier, a liquid carrier, a gaseous carrier, a bait or the like. Or, it is impregnated into a base material such as a mat, and if necessary, a surfactant and other auxiliary agents for formulation are added, and an aerosol, powder, granules, fine granules, tablets, oils,
It is used by formulating it as an emulsion, a wettable powder, a flowable agent such as an in-water suspension agent, an in-water emulsion agent, a non-heated transpiration agent, an aerosol agent, and a poison bait agent.

Examples of solid carriers used for formulation include clays (kaolin clay, diatomaceous earth, synthetic hydrous silicon oxide, bentonite, fubasami clay, acid clay, etc.), talc, ceramics, and other inorganic minerals (seri Examples of the liquid carrier include water, alcohols (methanol, ethanol, etc.), ketones (acetone, acetone, acetone, etc.). Methyl ethyl ketone, etc.), aromatic hydrocarbons (benzene, toluene, xylene, ethylbenzene, methylnaphthalene, etc.), aliphatic hydrocarbons (hexane, cyclohexane, etc.)
Kerosene, light oil, etc.), esters (ethyl acetate, butyl acetate, etc.), nitriles (acetonitrile, isobutyronitrile, etc.), ethers (isopropyl ether, dioxane, etc.), acid amides (N, N-dimethylformamide,
N, N-dimethylacetamide, etc.), halogenated hydrocarbons (dichloromethane, trichloroethane, etc.) dimethyl sulfoxide, soybean oil, vegetable oils such as cottonseed oil, and the like, and examples of the gas carrier, that is, propellant include freon gas, butane gas, Examples thereof include LPG (liquefied petroleum gas), dimethyl ether, carbon dioxide gas, compressed air, nitrogen gas and the like.

Examples of the surfactant include alkyl sulfates, alkyl sulfonates, alkyl aryl sulfonates, alkyl aryl ethers and polyoxyethylenated products thereof, polyethylene glycol ethers, polyhydric alcohol esters and sugars. Examples thereof include alcohol derivatives.

Examples of auxiliary agents for formulation such as a sticking agent and a dispersant include casein, gelatin, polysaccharides (starch,
Gum arabic, cellulose derivatives, alginic acid, etc.), lignin derivatives, bentonite, saccharides, synthetic water-soluble polymers (polyvinyl alcohol, polyvinylpyrrolidone, polyacrylic acids, etc.), and examples of stabilizers include PAP (isopropyl acid phosphate). ), BHT (2,6
-Di-tert-butyl-4-methylphenol), B
HA (mixture of 2-tert-butyl-4-methoxyphenol and 3-tert-butyl-4-methoxyphenol), vegetable oil, mineral oil, surfactant, fatty acid or ester thereof, and the like can be mentioned.

Examples of the base material of the non-heated transpiration agent include thermoplastic resin, filter paper, Japanese paper and the like, and examples of the base material of the poison bait agent include baits such as grain flour, vegetable essential oil, sugar and crystalline cellulose. Ingredients, antioxidants such as dibutylhydroxytoluene and nordihydroxyguaseletic acid, preservatives such as dehydroacetic acid, ingestion inhibitors such as capsicum powder, cheese flavors, and attractive flavors such as onion flavors.

The flowable agent generally comprises 1 to 75% of active ingredient, 0.5 to 15% of dispersant, and 0.1 to 10% of suspension aid (for example, protective colloid, compound imparting thixotropic property, etc.). ), 0-10% of suitable auxiliaries (eg
Antifoaming agent, rust preventive, stabilizer, spreading agent, permeation aid, antifreezing agent, antibacterial agent, antifungal agent, etc.). It is also possible to use an oil in which the active ingredient is hardly dissolved in place of water to prepare a suspension in oil. As the protective colloid, for example, gelanin, casein, gums, cellulose ether, polyvinyl alcohol and the like are used. Examples of the compound that imparts thixotropic properties include bentonite, aluminum magnesium silicate, xanthan gum, polyacrylic acid, and the like.

In these preparations, the present compound is contained as an active ingredient, or the total amount of the present compound and a pest controlling agent is usually contained in an amount of 1 × 10 ^{−7 to} 99% by weight.

In terms of dosage form, in the aerosol, the active ingredient is contained in an amount of 1 × 10 ⁻⁷ to 50% by weight, preferably 0.01 to 3%.
0% content, powders, granules, fine granules, tablets, oils, emulsions, wettable powders, flowables, etc., in a weight ratio of 1 × 10 ^-7
˜99%, preferably 0.01 to 50%.
Further, in non-heated transpiration agents, fuming agents, and poison bait agents, the active ingredient is contained in a weight ratio of 1 × 10 ⁻⁷ to 50%, preferably 0.01 to 20.
% Contained.

The present compound, which is an active ingredient of the pesticidal composition and the pesticidal composition of the present invention, has a low emergence-inhibiting effect of 0.001 to 0.01 ppm, preferably 0.002 to 0.01 ppm, on larvae of Drosophila species. It is effective enough even at a dose, and has an effect of inhibiting emergence on larvae of the fruit flies, which have been difficult to control until now.
0 to 1000 ppm, preferably 100 ppm to 100
It is sufficiently effective at 0 ppm.

The pesticide and the pesticidal composition of the present invention are generated from septic tanks, other sewage treatment facilities and the like, and inhabit therein, such as Drosophila melanogaster, Drosophila melanogaster, P. chinensis, P. scutellariae, Of the fleas such as thorned fruit flies, larvae, pupae and adults have an excellent effect in controlling the extermination and prevention of development, but at the same time, effective in exterminating unpleasant pests such as chironomids, spiders, also, When used for exterminating and preventing the development of unpleasant pests such as cockroaches, the content of the active ingredient in the above-mentioned various preparations is 0.1 to 99% by weight, preferably 0.2 to
It is 99%.

When the present compound or the present compound is used as an active ingredient of the pesticide or the pesticidal composition of the present invention together with a pest control agent, the application amount is usually 0.001 ppm to 1000 ppm in terms of the active ingredient concentration. And
Apply directly to aerosols, oils, tablets, non-heated evaporation agents, fumes, and poison bait. When an emulsion, wettable powder, flowable agent or the like is diluted with water and applied, the application concentration is 0.001 to 1000 ppm, and powder, granules,
The fine granules and the like are applied as they are without being diluted.

When used for the control of fly flies and fleas flies in a septic tank, a liquid substance that is insoluble in water and floats in water contains an active ingredient, and a liquid formulation such as an oil solution or an emulsion is made into sewage. Disperse or drip for processing. Also,
By blending this liquid formulation with a propellant as necessary to form an aerosol agent and spraying it into the septic tank,
It is possible to maintain efficacy.

The application amount and application concentration depend on the type of formulation, application time, application site, application method, degree of damage, etc., and may be increased or decreased without regard to the above range. can do.

[0031]

EXAMPLES Next, examples and comparative examples will be specifically described, but the present invention is not limited thereto. In the examples, "parts" means "parts by weight" unless otherwise specified.
Represents The pest control agent is indicated by the above compound number.

Example 1 (Efficacy test against Drosophila larvae) Thirty larvae of D. melanogaster (7 days after hatching) were planted in water mixed with the following test agents at a predetermined concentration. An untreated section in which no chemical was mixed was also provided, and the emergence inhibition rate was calculated from the treated and untreated sections using the following equation 1 3 test plots
Repeated times, the average value was obtained. The results are shown in Table 1.

[Equation 1]

Test agent No. 1 Compound No. 2 Compound: (1) = 1: 1 (weight ratio) No. 3 This compound: piperonyl butoxide =
1: 5 (weight ratio) Comparative Example 1 (1) Comparative Example 2 (2) Comparative Example 3 (4) Comparative Example 4 (5) Comparative Example 5 (3) Comparative Example 6 (6)

[0034]

[Table 1] Note 1: Drug concentration indicates the concentration as the total amount of drug. For example, the 0.01 ppm treatment group contains 0.005 pp of this compound
m + compound (1) means 0.005 ppm. Note 2: The drug concentration indicates the concentration of this compound.

Example 2 (Efficacy test against fleas fly larvae) A predetermined concentration of the above test agent was mixed in a medium composed of powder feed: bran: water = 1: 1: 2 (weight ratio), and larvae of fleas fly (4 after hatching). 20) were planted. An untreated section where no chemical was mixed was also provided, and the emergence inhibition rate was calculated from the equation 1 from the emergence rates of the treated section and the untreated section, as in Example 1.
The test was repeated 3 times and the average value was calculated. The results are shown in Table 2.

[0036]

[Table 2] Note 1: Same as above. Note 2: Same as above.

From the results of Examples 1 and 2, the pesticide and the pesticidal composition of the present invention are
It can be seen that the larvae of fleas flies show a higher lethal effect than existing insect growth inhibitors. Further, although the present compound alone shows a high lethal effect, a remarkable synergistic effect was observed when used in combination with an existing insect growth inhibitor or synergist.

Example 3 In order to carry out a field test of the pest control agent of the present invention in a septic tank of a general household, the pesticides having the formulations shown in Table 3 below were prepared.

[0039]

[Table 3] Test agent

Outline of Test [0040] A predetermined amount (No. 4 and 7 to 15) of each test agent was placed on the scum in the separated aeration type septic tank (5 to 10 person tank) of a general household.
Then, the treatment amount of this compound was 0.1 g / m ² per scum area.
No. In 5,6 The compounds throughput respectively 0.2 g / m ^2, so that 0.5 g / m ^2, also,
In Comparative Examples 7 to 10, (1) the treatment amount was 0.1 g /
m ² , 0.2 g / m ² , 0.5 g / m ² , 1.0 g / m
² was sprayed or sprinkled. In Comparative Example 11, it was suspended in the septic tank. After that, the number of adults of the fly and the flesh fly, which emerged from the septic tank, was investigated. The results are shown in Tables 4 and 5.

Number of individuals +++ 100 adults in the septic tank
More than ++ 30 to 99 adults in the septic tank + 10 to 29 adults in the septic tank ± 1 to 9 adults in the septic tank − 0 adults in the septic tank

[0042]

[Table 4]

[0043]

[Table 5]

With the dosage forms of the present invention (No. 4 to No. 15), the generation of fly flies and fleas flies was suppressed for 3 months after drug treatment, and long-term control was recognized. In particular, by mixing with a pyrethroid insecticide, it was possible to suppress the generation of harmful insects to a low density immediately after the treatment. Further, in the preparations (Comparative Examples 7 to 10) using the compound (1) which is an existing insect growth inhibitor, it was possible to suppress the occurrence of fruit flies, but in order to suppress the occurrence of flea flies, It is believed that a 10-fold or more dose of the compound is required. In Comparative Example 11 which is a conventional formulation (plate), the number of fly flies on the first day after the treatment decreased, and although the initial effect was observed, the number of the fly flies showed a tendency to increase from the first month after the treatment, No long-term control effect was observed.

[0045]

INDUSTRIAL APPLICABILITY The pesticidal composition and the pesticidal composition of the present invention exert an excellent pesticidal effect on the fruit flies and fleas of the flies, and since the effect lasts for a long time, septic tanks, other sewage treatment facilities, etc. Can occur from
It is effective for the simultaneous control of the fly flies and fleas flies that live there.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location (A01N 47/34 43:64) (A01N 47/34 43:88) (A01N 47/34 53: 00) (A01N 47/34 37:34) (A01N 47/34 31:14) (A01N 47/34 57:14) (A01N 47/34 57:12) (A01N 47/34 57:16) (A01N 47 / 34 57:28) (A01N 47/34 43:82) (A01N 47/34 47:22) (A01N 47/34 43:50)

Claims (8)

[Claims] 1. N-2,6-difluorobenzoyl-N '
2-Fluoro-4-trifluoromethylphenylurea as an active ingredient 2. N-2,6-difluorobenzoyl-N '
-2-Fluoro-4-trifluoromethylphenylurea and at least one pest control agent selected from the following group as an active ingredient: a butterfly fly / flea fly control composition insect Growth inhibitor Pyrethroid insecticide Pyrethroid insecticide Organophosphorus insecticide Carbamate insecticide Chlornicotine insecticide 3. A pest control agent for flies and fleas flies, characterized in that a synergist is added to the pest control agent according to claim 1. 4. An exterminating composition for fly flies and fleas flies, which comprises a synergist in combination with the exterminating agent according to claim 2. 5. N-2,6-difluorobenzoyl-N '
2-Fluoro-4-trifluoromethylphenylurea as an active ingredient 6. N-2,6-difluorobenzoyl-N '
2-Fluoro-4-trifluoromethylphenylurea and at least one pest control agent selected from the group below as an active ingredient: Insect growth inhibitor Pyrethroid insecticide Pyrethroid-like insecticide Organic phosphorus insecticide Carbamate insecticide Chlornicotine insecticide 7. A pest control agent for a septic tank, which comprises a synergist in addition to the pest control agent according to claim 5. 8. A composition for controlling septic flies and flea flies for a septic tank, which comprises adding a synergist to the exterminating agent according to claim 6.