Insecticides formulation

Tetrahydrofurfuryl alcohol is a solvent and coupling agent for a phosphate-type insecticide used to control the gypsy moth. Esters of tetrahydrofurfuryl alcohol are used in preparations employed as insect repeUents. Tetrahydrofurfuryl alcohol is also used as a solvent—carrier for an EPA-approved paper sHmicide formulation. In this appHcation, the exceptional solvent action of tetrahydrofurfuryl alcohol prevents separation of the... 

Baculovimses, especially nuclear polyhedrosis viruses (NPV) and granulosis viruses (GV), appear to be exceptionally well suited for IPM because of their extreme insect specificity. They are stomach poisons and are slow-acting. In vitro production is difficult and the products are more expensive than the bacterial insecticides. Their high host specificity is viewed as a commercial disadvantage, and improvements in formulations and appHcation techniques are needed. 

The successful employment of any insecticide depends on its proper formulation into a preparation that can be appHed for insect control with safety to the apphcator, animals, and plants. Insecticides are commonly formulated as dusts, water dispersions, emulsions, and solutions. The preparation and use of such formulations involves accessory agents such as dust carriers, solvents, emulsifiers, wetting and dispersing agents, stickers, and deodorants or masking agents (1). 

Insecticides. The use of iodine-based compounds as insecticides is of minor importance. The active ingredient is lodofenphos (142). It is formulated to be used in pubHc health and animal husbandry, eg, for cockroach control (see Insectcontroltechnology). 

Over 68 aerosol products containing isopropyl alcohol solvent have been reported (145). Aerosol formulations include hair sprays (146), floor detergents (147), shoe poHshes (148), insecticides (149,150), bum ointments (151), window cleaners, waxes and poHshes, paints, automotive products (eg, windshield deicer), insect repellents, flea and tick spray, air refreshers, disinfectants, veterinary wound and pinkeye spray, first-aid spray, foot fungicide, and fabric-wrinMe remover (152) (see Aerosols). 

Agricultural Products. Pesticides are frequendy appHed as emulsiftable concentrates. The active insecticide or herbicide is dissolved in a hydrocarbon solvent which also contains an emulsifier. Hydrocarbon solvent selection is critical for this appHcation. It can seriously impact the efficacy of the formulation. The solvent should have adequate solvency for the pesticide, promote good dispersion when diluted with water, and have a dash point high enough to minimise dammabiUty ha2ards. When used in herbicide formulas, low solvent phytotoxicity is important to avoid crop damage. Hydrocarbon solvents used in post-harvest appHcation require special testing to ensure that polycycHc aromatics are absent. 

Alkylphenol ethoxylates are chemically stable and highly versatile surfactants that find appHcation in a large variety of industrial products including acid and alkaline metal cleaning formulations, hospital cleaners, herbicides (qv) and insecticides, oil-weU drilling fluids, synthetic latices, and many others (see Disinfectants AND antiseptics Elastop rs, synthetic Insect control technology Metal surface treati nts Pesticides Petroleum, drilling fluids). 

MisceUaneous uses include extraction and purification of penicillin, alkaloids, vitamins, and flavors, and as an intermediate in the preparation of dyes and pesticides. Chloroform has also been used as a fumigant and insecticide, in the formulation of cough symps, toothpastes, liniments, and toothache preparations. These latter uses were banned by the FDA in 1976 (38). 

Other uses of hexachloroethane are as moth repellent, plasticizer for cellulose esters, anthelmintic in veterinary medicine, mbber accelerator, and as a component in fungicidal and insecticidal formulations. Hexachloroethane reacts with silumin (an aluminum /siUcon alloy) at 483 K to generate an intense white smoke, which is useful in certain pyrotechnics (154). 

Amongst synthetic quinoxalines, numerous types of biological activity have been reported. 5,6,7,8-Tetrachloroquinoxaline (132) and related halogenated derivatives have found use in fungicidal formulations. Phosphoric esters of 6-hydroxyquinoxaline (133) have found use in insecticidal preparations, and phosphoric ester derivatives of 2-hydroxyquinoxalines, such as (134), function as anthelmintics. 

NaF for water fluoridation, wood preservatives, the formulation of insecticides and fungicides, and use as a fluxing agent. It is also used to remove HF from gaseous Fz in the manufacture and purification of Fz-SnFz in toothpastes to prevent dental caries,... 

Microbial insecticides are very complex materials in their final formulation, because they are produced by fermentation of a variety of natural products. For growth, the bacteria must be provided with a source of carbon, nitrogen, and mineral salts. Sufficient nutrient is provided to take the strain of choice through its life cycle to complete sporulation with concomitant parasporal body formation. Certain crystalliferous bacilli require sources of preformed vitamins and/or amino acids for growth. Media for growing these bacilli may vary from completely soluble, defined formulations, usable for bench scale work, to rich media containing insoluble constituents for production situations (10,27). Complex natural materials such as cottonseed, soybean, and fish meal are commonly used. In fact, one such commercial production method (25) is based on use of a semisolid medium, a bran, which becomes part of the final product. 

The acyl groups introduced included 4-phenylbenzoyl, phenylacetyl, 4-methoxybenzoyl, acetyl, 2,4-dichlorophenoxyacetyl, and 2,2-dichloropro-pionyl. Introduction of the last pair of acyl groups is important because they are bioactive (insecticides), i.e., the product can be employed in controlled-release formulations [159]. The structures of all these esters were determined by FTIR and NMR spectroscopy, whereas their solution properties, includ-... 

Endosulfan is released to the environment mainly as the result of its use as an insecticide. Significant contamination is limited to areas where endosulfan is manufactured, formulated, applied, or disposed of. The compound partitions to the atmosphere and to soils and sediments. Endosulfan can be transported over long distances in the atmosphere, but the compound is relatively immobile in soils. It is transformed by hydrolysis to the diol and by microorganisms to a number of different metabolites. It is bioconcentrated only to low levels and does not biomagnify in terrestrial or aquatic food chains. 

As a result of its use as an insecticide on fruit trees, vegetables, and other crops, endosulfan is released directly to the atmosphere during application. The compound is applied principally by air-blast equipment or boom sprayers (WHO 1984). No information was found in the available literature regarding atmospheric releases from manufacturing or formulation operations, or occurrence of the compound in air samples collected at NPL sites. 

Although endosulfan is currently produced for use as an insecticide, information on the current production, import, and export of endosulfan by the United States is limited. Annual production volumes in the United States were 3 million pounds in 1980 (Sitfig 1980), and 10,000 metric tons (approximately 22 million pounds) worldwide were reported in 1984 (WHO 1984). However, as of 1982, endosulfan was no longer produced in the United States (HSDB 1999). Although U.S. imports of endosulfan are reportedly substantial, the most recent import information (182,000 kg) was for the year 1982 (HSDB 1999). Additional information on the producfion/formulation, import, and export volumes for endosulfan would be useful in assessing the extent to which, and conditions under which, humans may be exposed to endosulfan or endosulfan sulfate. 

The environmental fate and behavior of compounds depends on their physical, chemical, and biochemical properties. Individual OPs differ considerably from one another in their properties and, consequently, in their environmental behavior and the way they are used as pesticides. Pesticide chemists and formulators have been able to exploit the properties of individual OPs in order to achieve more effective and more environment-friendly pest control, for example, in the development of compounds like chlorfenviphos, which has enough stability and a sufficiently low vapor pressure to be effective as an insecticidal seed dressing, but, like other OPs, is readily biodegradable thus, it was introduced as a more environment-friendly alternative to persistent OCs as a seed dressing. 

---